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Hello and welcome to Noon Conference hosted by MRI Online

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Today we're honored to welcome Dr.

0:31

Sshh McCury for a lecture entitled Simplified Approach

0:34

to the Lymph Nodes of the Head and Neck.

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Dr. McCury currently holds academic appointments at numerous

0:40

institutions and serves as a national director of Head

0:43

and Neck Radiology at ProScan Imaging

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and Regional Medical Director at Envision

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Physician Services.

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His primary scientific interests have focused on

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investigating emerging metabolic

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and physiologic imaging techniques to evaluate head

0:56

and neck cancer and

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to differentiate recurrent tumors from

1:00

post therapeutic changes.

1:02

Dr. McCorey is a devoted educator

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and has been an invited speaker on over 500 occasions.

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We're grateful to him for his supportive MRI online

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and for serving as our head

1:11

and neck neuro-radiology advisor.

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At the end of the lecture, please join him in AQ

1:16

and a session where he'll address questions you may

1:18

have on today's topic.

1:20

Please remember to use the q

1:21

and a feature to submit your questions so we can get to

1:23

as many as we can before our time is up.

1:26

With that, we're ready to begin today's lecture. Dr.

1:28

McCury, please take it from here.

1:31

Hey, thanks Ashley. Thanks again for having me.

1:33

I love the, uh, music too. That was really good.

1:35

So anyway, thanks a lot for having me.

1:38

Um, the, uh, for the next uh, uh, hour

1:41

or so, um, we're gonna spend the time talking about

1:44

a simplified approach

1:45

to the lymph nodes of the head and neck.

1:47

So the lymph nodes are a very interesting part of the,

1:51

you know, the whole body as a whole,

1:52

but especially in the head and neck.

1:54

So the functions of the lymph nodes are to, first

1:57

of all transport lymphatic fluid,

1:59

and these are the third fluid of the body, if you will,

2:01

and we'll talk about that later.

2:04

Um, the lymph nodes filter for and substances.

2:06

So I always kind of think of the lymph nodes

2:09

as almost like the garbage bag

2:10

or the filtration device of our, uh, body

2:14

and also to initiate the immune response.

2:17

So those are three primary functions of the lymph nodes.

2:21

Now, you know, the lymph nodes of the head

2:23

and neck can be a little bit com uh, complicated,

2:26

but what I wanted to do was at least give you kind

2:28

of an approach to the lymph nodes

2:30

because, you know, if you don't do a lot

2:32

of head neck radiology, the lymph nodes can kind

2:34

of be a little bit challenging.

2:36

So, you know, I realize most

2:38

of you probably won't remember me tomorrow

2:40

or probably what I say,

2:42

but if I can just leave you with one concept

2:44

of the lymph nodes that's gonna maybe give you an approach

2:47

is just remember the lymph nodes.

2:49

If you have a dog or a cat, um,

2:51

or any type of pet, you know, they love

2:53

to be scratched under their chin like this.

2:55

So you know, if you ever, if you've ever done that

2:57

to your dog, you've been inadvertently palpating their

3:01

level one lymph nodes.

3:02

So the level one lymph nodes are gonna be under the chin.

3:05

Now the other concept that I wanna leave you

3:08

with is this string of pearls.

3:10

So the majority of the lymph nodes involved in the head

3:13

and neck are in this configuration

3:15

that look like the string of pearls.

3:19

So we're primarily gonna be focusing on these groups

3:22

of lymph nodes, the level one lymph nodes,

3:25

and this group of lymph nodes that are located in this

3:28

orientation that looks like the string of pearls.

3:31

Now there are other lymph nodes in the head

3:33

and neck area that we're not gonna be covering

3:35

purely because of time.

3:37

So there are lymph nodes in the paraic lens

3:40

or lymph nodes involving in the face,

3:42

and those don't nearly, uh, come into, uh, um, play as much

3:47

as the, the regular lymph nodes that we'll be discussing.

3:50

So just remember the, the, uh, petting your dog,

3:53

your cat on your chin,

3:55

and then if you like pearl necklaces, just realize

3:58

that the orientation

3:59

of levels 2, 3, 4, 5 in the supraclavicular lymph nodes just

4:04

look like a little pearl necklace

4:06

and we're gonna go through that in, in great detail.

4:10

So the, this was the classification of

4:13

how we define the lymph nodes.

4:15

Now, back when I was a fellow, I hate to say this,

4:17

but I, I was born in the last century

4:19

and I trained in the last century.

4:21

And when I started my fellowship back in 1992, um, at

4:25

that time we were looking at CT scans

4:28

and we were trying to separate the level two from the level

4:32

three lymph nodes.

4:33

And we're also trying

4:34

to separate the level three from the level four lymph nodes.

4:38

So if you look at this diagram right here,

4:40

you see this little vein right here that's actually, um,

4:44

draining into the internal jugular vein.

4:46

This is the facial vein

4:48

and this is the separation between level two

4:50

and level three that the surgeons look

4:52

for in the operating room.

4:55

Now from a CT standpoint, this is what we tried

4:58

to identify in cross-sectional imaging

5:00

and it was really, really painful to do that.

5:03

Um, just on cross-sectional imaging, remember this is really

5:06

before the days of reformats and everything.

5:08

And if you look at this muscle right here,

5:11

there's a muscle right here

5:12

that crosses over the internal jugular vein

5:15

and you can't see the internal jugular vein,

5:17

but it's just literally behind here.

5:19

And this is the omohyoid muscle.

5:21

So again, where the omohyoid muscle crosses the internal

5:24

jugular vein that separates level three and level four.

5:28

And we had to look for that on cross sexual inte imaging.

5:31

And that was really, again, really, really difficult.

5:34

So around that time, this the, you know,

5:38

radiology was kind of coming into its own, you know,

5:41

it was pretty well accepted

5:42

that we could see lymph nodes on ct.

5:45

And believe me, you know, back when I trained

5:47

that was kind of a revelation.

5:50

So over time, you know, the surgeon started to accept

5:53

that we could reliably identify lymph nodes on

5:57

cross sexual imaging.

5:58

So what the surgeons did,

6:00

and they worked with the radiologist

6:02

and they actually found out that a good approximator

6:06

for separating the level two

6:08

and the level three IE

6:10

where the this facial vein drains into the internal jugular

6:13

vein could be approximated by the hyoid bone.

6:16

And then where the omohyoid muscle crosses over the internal

6:20

jugular vein, which separates level three

6:22

and level four, well this could be approximated by the bates

6:26

of the cricoid cartilage.

6:28

So this is why when we start to look at lymph nodes,

6:31

why it's important to identify to understand

6:35

where the hyoid bone is

6:37

and the base of the cricoid cartilage is.

6:39

So if you've ever wondered why these two things have sort

6:42

of been so emphasized, that's the reason why.

6:46

So what I'm gonna do over the next uh, 10 minutes

6:49

or so is take a deep dive into these

6:52

various lymph node levels.

6:54

So we're gonna first start with the level one lymph nodes.

6:58

So the level one lymph nodes are comprised of the submental

7:02

and the submandibular lymph nodes.

7:04

And we'll go over these lymph nodes again

7:06

and separate these out.

7:08

But just realize that the level one lymph nodes extend from

7:12

below the mylohyoid muscle.

7:14

So when we look at the cross-sectional imaging,

7:16

this is the mylohyoid muscle here,

7:18

here's the mylohyoid muscle here

7:21

and it goes to above the level of the hyoid bone.

7:24

So there's our hyoid bone that's located here

7:26

and I'm gonna see if this is gonna work.

7:28

I think it's been working relatively better, but we'll see.

7:31

So anyway, there's the back of the submandibular gland.

7:35

So the level one lymph nodes are located anterior

7:38

to the back of the submandibular glands.

7:42

So those are the level one lymph nodes.

7:45

Now the level one lymph nodes are divided into the submental

7:49

lymph nodes and they're divided up into the

7:51

submandibular lymph nodes.

7:53

The submental lymph nodes are the level one A lymph nodes

7:57

and they're located between the anterior belly,

8:00

the digastric muscles.

8:02

So when you look between the digastric muscles,

8:03

you can see this fat right here

8:06

and within this fat right here we can see this

8:08

lymph node right here.

8:10

And that's a level one a lymph node.

8:12

Now you know, if you do a lot of head and neck radiology

8:16

and especially oncology,

8:18

the level one lymph nodes are sometimes resected in the

8:22

lymph node dissections.

8:24

Now sometimes on, on occasion the surgeons will go in

8:28

and they can resect the, some of the level one lymph nodes,

8:32

but sometimes if they're not careful they can

8:35

inadvertently retain these level one lymph nodes

8:38

between the anterior belly, the digastric muscles.

8:41

So from a radiology standpoint, you know,

8:43

when you're looking at these post-treatment changes,

8:46

pay close attention between the anterior belly

8:48

of the digastrics 'cause I've seen several cases of patients

8:52

that have undergone dissections in this lymph node group,

8:55

but there's been recurrences and that's

8:57

because some of these lymph nodes have been retained.

9:00

Now the level one B lymph nodes are in the same general

9:04

location, but they're lateral to the anterior belly

9:07

of the di gastric muscles.

9:08

So the, again, the level one A are

9:11

between the anterior bellies

9:12

and the level one Bs are posterior lateral.

9:15

So they're lateral to the anterior belly

9:17

thetic gastric muscles.

9:18

But remember these level one lymph nodes are the ones

9:21

that are right below your chin.

9:23

So those are the ones

9:24

that you can occasionally run into if you pet

9:27

your dog or your cat.

9:30

Now the level two lymph nodes run from the skull base

9:33

and they go down to our friend the hyoid bone.

9:36

So we're gonna be coming back

9:38

to our little friend right here.

9:40

Now what we do is we take that same line right here

9:43

and we touch the back of the sub man Dior glands

9:46

and the level two lymph nodes are everywhere located behind

9:51

the submandibular gland.

9:53

So those are our level two lymph nodes.

9:55

So they run from the skull base all the way down

9:58

to the hyoid bone.

9:59

But unlike the level one lymph nodes which are anterior,

10:03

the level two lymph nodes are gonna be posterior.

10:07

Now when you look at these lymph nodes,

10:09

there's actually a level two A and a two B.

10:12

And unless you do head

10:13

and neck radiology, I don't really expect you

10:15

to remember these, but it is, you know,

10:18

fairly straightforward.

10:19

The only difference between A two A

10:21

and a two B is that there is no discernible fat plane

10:25

between the lymph node here and the internal jugular vein.

10:29

But on the other hand, when we look at the level two B lymph

10:33

nodes, we can see a fat plane here between the lymph nodes

10:37

and the internal jugular vein.

10:39

So that's the main difference between the level two A

10:43

and the level two B lymph nodes.

10:47

So now what we're gonna do is we're

10:49

gonna continue our journey.

10:50

So what we did so far is

10:52

that we talked about the level one lymph nodes which are

10:55

located below the chin.

10:57

Then we talked about these level two lymph nodes

10:59

and they run from skull base down to the level

11:02

of the highway bone.

11:03

Now we're gonna continue our journey

11:05

and we're gonna transition from red to green.

11:08

And this green right here is located between the hyoid bone

11:14

and the base of the cricoid cartilage.

11:16

And if you look at the diagram at the top left,

11:18

there's our little internal uh, excuse me, the facial vein

11:21

that goes into the internal jugular vein.

11:23

There's the omohyoid muscle right here,

11:27

but again, these are approximated by the hyoid bone

11:30

and the base of the cricoid cartilage.

11:33

So we are just come continuing our journey

11:36

and this is the example of the level three lymph nodes.

11:39

So when you look at the left hand side, we're go from here

11:42

to here and in red.

11:44

And these are two examples here of level three lymph nodes.

11:47

So here's a lymph node right here, this is at the level

11:50

of the thyrohyoid membrane

11:53

and there's another lymph node right here,

11:55

which is metastatic on the right and on the left.

11:58

But notice how they are at the level of the CRICO cartilage,

12:01

but they're above the base of the CRICO cartilage.

12:05

So remember the, the transition between three

12:07

and four has to be the base of the cricoid cartilage.

12:11

So if you're looking at AN CT

12:13

and you actually see the crico retinoid joint, just realize

12:16

that this is still a level three lymph node.

12:21

Now we're gonna now talk about the level four lymph nodes.

12:24

So the level four lymph nodes on the diagram on the upper

12:27

right go from the green to the purple

12:31

and the level four lymph nodes run from the base

12:33

of the crico cartilage down to the level of the clavicles.

12:37

Now I kind of joke about this

12:39

and I say when I talk about the level four lymph nodes,

12:43

I kind of cheat a little bit.

12:45

If you read the paper that I referred to

12:47

before, technically the level four lymph nodes run from

12:52

the posterior aspect of this muscle,

12:54

which is the sternocleidomastoid muscle

12:57

along the anterior portion of this muscle right here,

13:01

which is the anterior scaling muscle.

13:04

So the level four lymph nodes are gonna be right

13:06

where my arrow is.

13:08

So on the opposite side,

13:09

and I'm gonna see if I can do this here.

13:12

Um, sorry about that, I'm gonna see if I can do this.

13:14

Oops, there we go.

13:17

Um, let's sit. There's my pen.

13:21

So I'm gonna see if I can draw a line right here from the

13:24

back of the sternal kind of mastoid muscle

13:26

to the anterior scaling.

13:28

So the level four lymph nodes are gonna be right in here.

13:32

Now that's technically what you're supposed to do.

13:35

Now I have to admit when I am doing this I tend

13:39

to cheat a little bit.

13:40

So just to stay with the same convention that I use

13:43

for the other lymph nodes, I tend to draw a line right here

13:47

that connects the back of both sternocleidomastoid muscles

13:51

and in general that gets me to the right vicinity.

13:54

So again, if you can't remember all the details about how

13:57

to draw the level four, I think if you just draw

14:00

that line connecting the back

14:01

of the sternocleidomastoid muscles

14:04

between the crico cartilage

14:05

and the clavicles, I think you should be just fine.

14:08

And again, just a level set right here we're dealing

14:11

with this group of lymph nodes that are I

14:14

that are identified by the purple.

14:17

So here's an example of the level four lymph nodes,

14:22

a level four lymph node here

14:24

and there's another level four lymph node here.

14:26

And what I did in this particular case,

14:28

I just drew a line right here that connects the back

14:31

of the sternocleidomastoid muscle to the anterior scaling.

14:34

There's that level four lymph node

14:36

and this yellow arrow again points at a

14:39

level four lymph node.

14:41

So what have we done so far?

14:42

So just to reiterate, we started here,

14:45

which was at the level one, then we were at level two,

14:49

which runs from the skull base down to the hyoid bone.

14:53

Level three was hyoid bone down to the base

14:55

of the crico cartilage.

14:57

And level four was from the cricoid cartilage down

15:00

to the level of the clavicles.

15:03

So now what we're gonna do is we're gonna turn our attention

15:07

to the level five lymph noss.

15:10

So when we look at this lymph node group,

15:12

if we look at the anterior limb of our pearl necklace,

15:15

remember our pearl necklace, basically we divided

15:17

that anterior limb

15:18

of the pearl necklace into three separate levels, level two,

15:22

level three, level four.

15:24

The level five lymph nodes is basically the posterior limb

15:28

of that pearl necklace.

15:30

So this runs all the way down from the skull

15:33

base to the clavicle.

15:34

So technically this is geographically the largest area of

15:39

that lymph node group all the way from the skull base down

15:42

to the level of the clavicles.

15:44

So when we look at this on the, on the axial images,

15:48

here's our skull base, here's our clavicles.

15:51

If you draw a line right here that connects the back

15:54

of the sternocleidomastoid muscle, what we've talked about

15:58

with level two, three

15:59

and four, when we connected this line back here,

16:03

we were looking at uh, essentially everything here.

16:08

These constituted two, three, and four.

16:11

But for the level five lymph nodes, we take

16:14

that same line from the back

16:16

of the sternocleidomastoid muscle

16:18

and we extend it all the way back to the trapezius.

16:21

So from the trapezius to the back

16:22

of the sternocleidomastoid muscle, this is all part

16:26

of the level five lymph node.

16:28

So when again, when you look at

16:30

that full geographic distribution,

16:32

the level five lymph nodes is the largest lymph node group.

16:38

So the level five lymph nodes are fascinating to me.

16:41

I think all of head and neck is fascinating.

16:44

So here's an example of a level five lymph node,

16:47

classic level five lymph node.

16:50

Here's our sternocleidomastoid muscle,

16:52

if I drew a line right here, it's connecting the back of it.

16:55

So unequivocally a level five lymph node.

16:57

Here's another lymph node right here.

17:00

This is at the junction of level three and level five

17:03

because we're at the level of the thyroid cartilage.

17:06

So the bottom line here is that if you see

17:09

isolated level five lymph nodes, you know, you have to think

17:14

of other things besides just the routine

17:16

head and neck cancers.

17:18

So first of all, level five lymph nodes,

17:21

it can be associated

17:22

with nasal pharyngeal carcinoma, no doubt about it.

17:25

But on the other hand, if you see isolated level five lymph

17:29

nodes, you have to think of other types of cancers.

17:32

So specifically we have to think of skin

17:35

cancers arising from squamous cell carcinoma.

17:38

So yes, this is squamous cell carcinoma

17:41

but it's not arising from the visceral space

17:43

but rather it's a skin cancer.

17:45

And you also have to think of melanoma.

17:48

So you know, I was just in Australia a few weeks ago

17:51

and you guys probably know I see patients once a week

17:54

and yesterday I was in clinic, um,

17:57

and we saw a patient that came in with a scalp cancer

18:00

and actually presented with a level five lymph node.

18:03

So we examined him and he had a big cancer on his skin.

18:06

It was literally right right about the ear,

18:08

it was about a three centimeter fungating mass there.

18:12

And, and you know we talk about protection, right?

18:16

We say about from cancers, right?

18:18

So you know, you don't wanna smoke, you,

18:20

you don't wanna drink.

18:21

Um, and those are things

18:22

that can help you prevent head and neck cancer.

18:25

But one of the big things is

18:27

to wear a hat and cover yourself.

18:29

So this guy, he was a nice guy

18:30

and he, he just readily admitted, yeah,

18:33

I've got a skin cancer, I've got a hat, but I never wear it.

18:36

And he knows full well you gotta wear your hat.

18:39

And so especially if you're of light-skinned fair skin

18:42

and you're out in the sun a lot

18:43

and this guy was out in the sun a lot,

18:45

he was actually a construction worker, never wore his hat.

18:48

It just reiterates the fact that one prevention for head

18:51

and neck cancers is to wear the hat.

18:54

So don't not only wear the hat,

18:55

make sure your ears are covered

18:57

and make sure the back of your neck is covered as well too

19:00

because I can't tell you.

19:02

Uh, other thing too, I've seen a bunch of patients

19:04

that are wear a hat but they don't cover their ears.

19:06

So they have these cancers involved in their pena.

19:09

So for peak's sake, if you're out in the sun a lot

19:11

and you really are fair skinned, please wear a hat.

19:14

'cause for me that's just as important for not smoking and

19:17

and drinking to prevent these types of cancers.

19:20

And then finally you can have thyroid carcinomas two, uh,

19:25

that can present with these level five lymph nodes.

19:27

So again, this is one of these really interesting groups

19:30

and if you do see these isolated level five lymph nodes,

19:33

think of these potential causes.

19:37

So the level six lymph nodes are again another interesting

19:40

group of lymph nodes.

19:42

So what I'm showing here is a metastatic lymph node

19:45

that's located at the CRICO retinoid joint.

19:49

So this would be a level three lymph node

19:51

because it's lateral to the carotid artery.

19:54

The level six lymph nodes are also known

19:57

as the visceral lymph nodes

19:59

and they run from our friend the hyoid bone

20:02

down to the manubrium.

20:03

But the key thing about the level six lymph nodes is they're

20:07

actually located between the internal carotid artery.

20:11

So these are sometimes also referred to

20:13

as a trache esophageal groove, lymph nodes,

20:16

the TE groove lymph nodes.

20:18

So these are the level six lymph nodes.

20:21

So when we see level six lymph

20:23

nodes, what do we think about?

20:25

Well, here's an example

20:26

of a level six lymph node here we can see this necrotic mass

20:30

right here and we can see a little calcifications

20:33

on the opposite side.

20:34

We see it's other lymph node.

20:36

In this case it's not as classic as a one on the right side.

20:40

You can see the carotids pushed a little bit anterior,

20:42

but again we can see a little calcification.

20:45

So if you understand,

20:47

and you're pretty smart right here, you can figure out

20:50

what the cause of this is

20:52

because this type of primary site predisposes you

20:56

to develop metastatic level six lymph nodes.

20:59

And in this case this was from the thyroid gland

21:02

and this was papillary thyroid carcinoma.

21:05

So there are certain primary sites that predispose you

21:09

to developing metastatic level six lymph nodes.

21:12

They are the thyroid gland,

21:14

which I just mentioned the esophagus.

21:17

Anytime that you have tumors involving the piriform sinus

21:20

that extend to the apex of the piriform sinus.

21:23

And if you have a true vocal port carcinoma

21:26

with subglottic extension, these all predispose you

21:29

to developing level six lymph nodes.

21:32

Another example here,

21:34

here's a metastatic right lymph node medial

21:36

to the carotid artery located

21:39

in the tracheal esophageal groove.

21:42

And this is a TE groove level six lymph nodes.

21:46

Now why are they important?

21:48

They're important for a couple of reasons.

21:50

Number one, when you are going to an ENT surgeon,

21:55

what they end up doing is they do a thorough

21:57

evaluation of your neck.

21:59

Now when they palpate your neck,

22:01

they're pretty good at identifying the levels

22:04

1, 2, 3, 4, and five

22:07

and the supraclavicular lymph nodes, which we'll talk about.

22:11

But on the other hand, this lymph node is really deep,

22:13

it's right next to the tracheal esophageal groove.

22:16

So this is a very blind area, they can't see that.

22:20

The second thing is

22:22

that the standard neck dissections are performed

22:25

for the level one through five lymph nodes.

22:28

In order to surgically resect these level six lymph nodes,

22:31

they have to do a different type of nodal dissection

22:34

and that's referred to a central neck dissection.

22:38

So in the central neck dissection,

22:40

the surgeons specifically go in

22:42

and remove the trache esophageal groove lymph nodes.

22:45

So if we see an unexpected central compartment lymph node

22:49

like this, then the surgeons are gonna have

22:51

to alter their approach regarding neck dissections

22:54

and specifically perform a central neck dissection.

22:59

And this is just a little thing that I learned years ago.

23:01

This is also a level six lymph node.

23:04

This was my first exposure to the level six lymph node.

23:07

This is actually a pretracheal lymph node.

23:10

Notice how it's located

23:11

between the internal carotid arteries

23:13

and this is what we lovingly referred to

23:16

as the delian lymph node named after the oracle of Delphi.

23:20

So rumor has it is

23:21

that people would travel from far away to meet the oracle.

23:25

She would palpate your anterior neck

23:28

and if she felt something hard

23:30

that usually indicated you weren't gonna live very long

23:33

and that's why it was called the Delphi and lymph node.

23:37

Well the level seven lymph nodes are the

23:40

mediastinal lymph nodes.

23:41

Now I don't necessarily like these lymph nodes,

23:43

I wish they sort of weren't included in the head and neck,

23:46

but they are to me these are lymph nodes

23:49

that should be covered by our chest radiologists.

23:51

But on the other hand, what it always makes me do,

23:55

because it is part of our head

23:56

and neck lymph node classification, it always forces me

24:00

to look at the mediastinum

24:01

and to look at the lungs as well too.

24:04

So the level seven lymph nodes run from the top

24:06

of the manubrium down to the inmate vein.

24:09

So remember all these neck cts always end up

24:12

clipping the top of the chest.

24:14

So we, we are responsible to look

24:16

for the mediastinal lymph nodes

24:18

and then also responsible to look

24:20

for the lung fields as well.

24:24

Well the next lymph node group

24:27

is gonna be the supraclavicular lymph nodes.

24:30

So if you remember I began this discussion

24:33

about talking about the string of pearls.

24:36

And so the anterior limb of the string

24:38

of pearls was the level two, the level three,

24:40

the level four, and the level five lymph nodes.

24:45

So what c what connects the level four and the level five?

24:48

Well it's this group of supraclavicular lymph nodes.

24:52

Now the supraclavicular lymph nodes are about the level

24:55

of the clavicle, the lateral to the carotid artery

24:58

and they're above and medial to the ribs.

25:00

So when I look at the supraclavicular lymph nodes,

25:04

what I do is that if I see the C clavicle

25:07

and I look at the fat deep to the clavicle,

25:09

any lymph nodes in this area,

25:12

I consider supraclavicular lymph nodes.

25:14

Now technically it's really hard to separate level four

25:19

and the SCL lymph nodes and level five

25:22

and the SCL lymph nodes.

25:23

It's really, really hard to do this

25:25

and there have been various ways

25:27

that it has been done specifically looking at the vase veins

25:31

in the thro cervical trunk.

25:32

But just in a couple of slides you'll see how

25:35

I'm not the only one that's had a problem with that.

25:38

In fact, we've adjusted that in one of the staging systems

25:41

for the lymph nodes of the head

25:43

and neck to make it a little bit more consistent.

25:45

So sometimes if you do have problems, uh,

25:47

separating four from the supra claves

25:49

or five from the supra claves,

25:51

just realize you're not the only one.

25:55

Now the supraclavicular lymph nodes are again a very unique

25:59

group of lymph nodes

26:00

because when we talk about levels one through five,

26:03

we're primarily looking at head

26:05

and neck cancers involving the upper air digestive tract

26:09

that metastasize to levels one through five.

26:12

But if you have isolated groups

26:14

of lymph nodes involving the supraclavicular lymph nodes,

26:17

this is a transition zone.

26:19

So realize these lymph nodes can become metastatic from

26:24

tumors involving the upper air digestive tract.

26:27

You could have tumors

26:28

that actually arise in the lymph nodes,

26:30

but you can also have, sometimes it's anti-gravity,

26:33

you can have tumors below the clavicle metastasizing

26:36

to the supra CLA lymph nodes.

26:39

So if you see this isolated supraclavicular lymph nodes,

26:42

think of nasopharynx

26:43

and hypopharynx, these are, uh, a part

26:46

of the normal upper air digestive tract.

26:48

They can involve the supra CLA lymph nodes.

26:51

If you have lymphoma, Hodgkin's lymphoma can present

26:55

as an isolated supraclavicular lymph nodes.

26:58

Or you can have these other lymph nodes that are

27:01

below the clavicle that have lymph nodes, uh, uh, channels

27:05

that go to the supraclavicular lymph nodes.

27:07

So think of lung, think of breast, think of esophagus, think

27:11

of GI and think of pancreas.

27:14

So again, that supra CLA lymph nodes as I always call 'em,

27:17

transition zone lymph nodes.

27:19

So we have to think above the clavicles below the clavicles

27:23

and also lymphoproliferative disorders

27:25

that present right at the SCL lymph nodes.

27:30

Now as I mentioned

27:31

before, sometimes the SCL lymph nodes can be hard

27:35

to specifically identify.

27:37

So in the eighth edition

27:40

of the nasal pharyngeal cancer staging,

27:43

we made it a little bit easier so you don't have to kind

27:46

of have a tussle as to where the,

27:48

the level four in the supra CLA begin.

27:51

So regarding N three disease, what we now say is

27:55

that N three disease for uh,

27:57

nasal pharyngeal lymph nodes are any lymph node groups

28:01

that are below the coddle border of the cricoid cartilage.

28:05

So if you actually look at the CRICO cartilage,

28:07

what we're saying is that if you draw a line

28:09

through the CRICO cartilage level four, the inferior portion

28:13

of five, and also the supraclavicular lymph nodes,

28:17

if they're involved with NPC, we'll upstage 'em.

28:20

So we don't specifically have to look

28:21

for supra cla lymph nodes and see where that separation is.

28:24

So this gives us a little bit more standard approach when

28:28

we're looking at these lower lymph nodes.

28:32

Well this last group

28:34

of lymph nodes is the retro pharyngeal lymph nodes.

28:37

So I'm not giving a talk on the spaces,

28:39

but I'll just give you a little bit of a primer.

28:42

So you know, this little fascial layer right here

28:45

has numerous names to it.

28:47

I still call this the visceral fascia.

28:49

Other people will call it the fingal mucosal fascia.

28:52

Some people call it the fingal basler fascia.

28:55

It doesn't really matter what you say it is,

28:57

but just realize that there's a fascial layer.

29:00

Now the other space that's located just anterior

29:03

to this fascia is called the fingal mucosal space

29:07

or the visceral space or just called the pharynx.

29:10

Well what do you call the space that's behind the pharynx?

29:13

Well that's the retro pharyngeal space.

29:15

And within the retro pharyngeal space you have these lymph

29:18

nodes and there's two groups of lymph nodes.

29:21

You have a medial group and lateral groups,

29:24

and these are the retro pharyngeal lymph nodes.

29:26

They're also known as the nodes of rase.

29:29

So these retro pharyngeal lymph nodes a very important group

29:33

because again, they cannot be palpated

29:36

by our referring physicians.

29:38

There are surgeons end up palpating the neck, there's no way

29:42

that they can feel these lymph nodes.

29:44

So these are our lymph nodes.

29:46

So these lymph nodes are located just medial

29:49

to the internal carotid artery.

29:51

There's one, and here's another one right here.

29:54

Here's the carotid artery

29:55

and there is a metastatic retropharyngeal lymph node just

29:59

medial to, in fact, yesterday we had another patient present

30:03

with a large nasopharyngeal mass

30:05

and actually had bilateral retro pharyngeal lymph nodes

30:08

that again, were not palpable on clinical examination.

30:12

So it's important for us to be aware

30:14

of these retro pharyngeal lymph nodes.

30:19

So what we've done so far is

30:20

that we've taken a really deep dive into the anatomy

30:25

of the lymph nodes of the head and neck

30:27

and we talked about the levels of the lymph nodes.

30:30

We went all the way through one through seven.

30:32

So that is exactly what these the,

30:34

where these lymph nodes are located.

30:36

But why do we spend so much time

30:40

looking at these lymph nodes?

30:43

Well, the reason is, is

30:44

that if there is a positive lymph node,

30:47

this reduces survival by 50%.

30:49

Now think of that 50% is a big, big number.

30:53

So if we the radiologist say that there's a

30:56

positive lymph node, the survival of that patient is reduced

30:59

by 50%.

31:01

Now when we look at these lymph nodes based on imaging,

31:05

we have our own imaging criteria.

31:08

Now the first point that I wanna make is

31:10

that when we look at the criteria for lymph nodes,

31:13

there are limitations to this.

31:15

So I show this image on the right

31:17

and I specifically wanna point out the orientation

31:20

of the lymph nodes in levels 1, 2, 3, and five.

31:25

The lymph nodes are like these kidney beings right here.

31:28

So they're located at 1, 2, 3,

31:30

and five in the cranial coac dimension.

31:33

But on the other hand, look at the lymph nodes in level one

31:36

and look at the supraclavicular lymph nodes.

31:39

They're laying on their side.

31:40

So this kidney bean is on their side.

31:43

Now if this patient was having a neck ct,

31:46

they'd be on their back

31:47

and then we would end up forming cross-sectional imaging.

31:51

And when you do a CT scan, notice how in level two the plane

31:56

of that scan is going to be going right

31:58

through the mid portion of that lymph node.

32:01

So we're gonna have a true axial dimension.

32:04

But on the other hand, if we use that same plane,

32:07

if we're going through level one notice, we're going

32:11

through the long axis, we're actually going

32:13

through the top to bottom.

32:15

So based on the orientation of the lymph nodes,

32:18

when we look at the size criteria,

32:20

they're gonna be inherent problems with the size criteria.

32:25

So these are the standard accepted size criteria.

32:29

When we look in the head

32:31

and neck, what we do is that we look at the axial plane

32:35

and we measure the largest axial dimension.

32:39

Now this is different than the chest

32:40

and the abdomen where you would be measuring in this plane.

32:44

So in the head and neck we do things different.

32:46

In fact, if I look at the left hand side, if I was

32:49

to measure this based on head

32:51

and neck, I would draw my plane like this.

32:53

If this happened to be in the chest

32:54

or the abdomen, I would draw it like this.

32:57

So we do our convention differently than compared

33:01

to anywhere else in the body.

33:03

Now you have to ask yourself why do we do it like that?

33:07

The reason is that there was a paper written back

33:10

around 2000

33:11

that was a perspective study in which we've measured the CT

33:16

and MRI measurements of these lymph nodes using this

33:20

orientation and we compared it to pathology.

33:24

This is where this convention arose from.

33:26

And since then there have been many different types.

33:28

But the standard accepted size criteria are 10 millimeters

33:32

for level 1, 3, 4, and five

33:37

and 15 millimeters for level two

33:39

and the retro pharyngeal lymph nodes.

33:41

Now the retro pharyngeal lymph nodes were not included in

33:44

this study, but levels one through five were included.

33:47

So these are the standard accepted size criteria

33:50

and this is why we do it based,

33:53

it was based on this particular study.

33:56

Now one thing that oftentimes gets confusing,

33:59

and I wanna point this out right now, is that if we

34:03

as the radiologists say

34:05

that there is a level three lymph node greater than 10

34:08

millimeters or level two lymph nodes greater than 15

34:12

millimeters, we're gonna call that a positive lymph node.

34:15

This is our criteria.

34:17

But when we look at the staging, an upper limit

34:21

of N one disease is three centimeters.

34:24

So there's a little wiggle room for that lymph node to grow

34:27

between by the time it reaches this upper threshold for us

34:31

to call metastatic from the time we transition from N one

34:36

to N two disease.

34:37

So just realize three centimeters is the upper threshold.

34:41

So again, that can get a little bit confusing sometimes,

34:44

but I did wanna point that out,

34:45

that little bit of a wiggle room.

34:49

Now the size criteria, as I mentioned

34:52

before, is kind of fraught with errors

34:55

and there are other ways where we can try to look

34:59

for metastases to improve our diagnostic accuracy.

35:04

And in order to enter this discussion, I wanted

35:07

to go over the regular anatomy of the lymph nodes.

35:10

Now like every other organ,

35:13

there's an artery and there's a vein.

35:15

So we all know this,

35:16

in every organ there's an artery in a vein,

35:19

but in a lymph node we have the third vessel

35:21

and that third vessel is the lymphatic vessel.

35:24

Now, unlike the artery in which the artery enters at the

35:29

hilum of a lymph node, the afer lymphatic vessels enter

35:34

through the periphery of the lymph nodes.

35:36

So we have this lymph vessels coming in,

35:39

it enters the periphery

35:41

and then eventually it flows centrally

35:44

and then it leaves this lymph node, uh, vessel

35:47

through the efferent vessels.

35:50

So this is where the filtration occurs, this is where

35:52

that immune response occurs.

35:55

It's this transition

35:56

of the lymphatic fluid from peripherally to centrally.

36:01

So if you understand that, then you realize

36:04

that if you have a squamous cell carcinoma involving a

36:08

certain area and it invades the lymphatics,

36:11

the earliest deposition of these lymph nodes are going

36:15

to be in the periphery of the lymph node.

36:18

So this is an example of a histologic specimen

36:21

of a squamous cell carcinoma involving the

36:24

periphery of a lymph node.

36:26

This is an example of a lymph node.

36:28

This was less than 1.5 centimeters.

36:31

And we can see the small peripheral low attenuation deposits

36:35

within the capsule of the lymph nodes.

36:38

So again, early metastases.

36:40

Now this is an example of a lymph node

36:42

that's completely replaced by tumor.

36:45

In fact, when we start talking about these lymph nodes

36:49

and they exceed their size criteria,

36:52

these lymph nodes are already chockablock full of tumor.

36:55

They're already filled with tumors.

36:57

So the size criteria is actually a late finding.

37:01

It's not an early finding, it's a late finding.

37:04

And the earliest findings are gonna be the small little

37:07

peripheral area of metastases.

37:09

And the reason is is

37:11

because the afar lymph vessels,

37:14

these fluid initially drains into the

37:16

periphery of the lymph nodes.

37:19

So as a result, we're still unable

37:22

to detect these small little micro metastases

37:25

because 40%

37:27

of metastatic lymph nodes are less than seven millimeters.

37:30

So the downside is is that if you look at any

37:33

of these techniques, including spectral CT

37:35

and photon counting, the the latest thing

37:38

that's coming out in ct,

37:39

we still cannot detect micro metastases.

37:42

We do a pretty good job, our negative predictive values

37:45

somewhere between 90 and 95% if we use PET CT or PET mr.

37:50

But again, we still can't detect these little

37:53

smaller lymph loads.

37:55

But on the other hand, you know, there are certain things

37:58

that we can do and I always say there's a difference

38:01

between science versus art.

38:03

So the science if you will,

38:05

is the size criteria that we use.

38:08

But what about the art?

38:10

You know, if you can identify

38:12

and are comfortable with head

38:15

and neck lesions, you can use other criteria

38:19

to help you improve your diagnostic accuracy.

38:22

So here on the top left, it's a standard size criteria.

38:26

Now here's an example of a lymph node

38:28

that's about one centimeter or so, but is cystic.

38:31

And if I told you this patient had thyroid carcinoma,

38:34

well you can make the diagnosis

38:36

of metastatic thyroid carcinoma.

38:39

Here is a patient, a child that has calcifications.

38:42

Now this is less than 1.5 centimeters,

38:45

but on the other hand, if I told you, hey,

38:47

this patient has a history of neuroblastoma,

38:50

you can make the diagnosis of neuroblastoma similar

38:53

with osteosarcoma.

38:55

This was an example of tumor that extends

38:57

outside of the lymph nodes.

38:59

This was extra nodal extension.

39:01

I'm gonna come back to this

39:02

because this is a supportive diagnosis

39:06

but not a a firm diagnosis and we'll see why.

39:09

But realize you can have these lymph nodes, um,

39:13

tumors extending outside of the capsule of lymph nodes

39:16

if you have clumping of lymph nodes.

39:18

What if I told you this patient had a

39:20

right-sided head and neck cancer?

39:22

You look real closely

39:23

and we see multiple clumped lymph nodes.

39:25

Well guess what? That's a sign of metastases

39:28

because look at the opposite side, nothing's there.

39:32

And this is an example of hypervascular lymph, no.

39:34

So if I told you this patient had thyroid carcinoma,

39:38

again we can make the diagnosis

39:40

of a metastatic lesion even though it's less

39:42

than the size criteria.

39:44

So these are some other diagnostic size criteria

39:47

that can help us be a little bit more accurate.

39:52

And sometimes in, you know,

39:53

in lymph nodes we can make the specific diagnosis.

39:56

So this was an example.

39:58

If I told you as an elderly male

40:00

and we see the cystic lesion here, we can make the diagnosis

40:03

of HPV positive oral pharyngeal metastases.

40:07

If I told you you see this,

40:09

we can see a cystic hypervascular calcifications.

40:12

We can make the diagnosis of papillary thyroid metastases.

40:16

This patient has multiple large lymph nodes

40:19

involving both neck.

40:20

We can make the diagnosis in this case of CLL,

40:23

this could have easily been lymphoma,

40:25

but in this case it was CLL.

40:27

And this was an interesting case.

40:29

I remember I saw this patient in clinic initially clinically

40:32

they thought they had lymphoma,

40:34

but when I saw this I said, well here's a clump group

40:37

of lymph nodes involving the level one lymph nodes.

40:40

If you look real closely, we can see some reticulation.

40:43

You know, we ask them, uh, if they had cats.

40:46

And lo and behold, this young man had 11 cats.

40:49

Don't ask me why the young man had 11

40:51

cats, I don't want to go there.

40:53

But he loved his cats

40:54

and this in fact was cat scratch disease.

40:56

And this was a, a young child

40:58

that ended up having a sore throat, uh,

41:01

difficulty swallowing.

41:02

And this was separative adenitis involving the retro

41:05

pharyngeal lymph nodes.

41:07

So sometimes we can actually make specific

41:10

criteria if we're comfortable

41:12

with these additional differential findings,

41:15

but occasionally we can't have alligators.

41:17

And these are some of the things, um,

41:20

that I've actually missed.

41:21

I'll tell you the ones that I missed. I missed this one.

41:24

This was a patient when I was at UNC.

41:27

Uh, we present this patients

41:29

to the head and neck tumor board.

41:31

I saw this case and I thought this was a metastatic

41:33

level two lymph node.

41:35

You know, I gave a beautiful diagnosis,

41:38

the biopsy came back negative multiple times and lo

41:41

and behold, we tested for PPD

41:43

and this was tuberculous adenitis.

41:45

So I completely missed that one.

41:47

This is one we actually got right?

41:49

And this was a case, a patient

41:51

that ended up having melanoma.

41:53

So this is metastatic melanoma

41:55

to the right side of the neck.

41:57

When we look at the opposite side, we see all

42:00

of these lymph nodes here in the left,

42:02

this patient also had a history of breast cancer.

42:05

So the issue was, was this melanoma or was it breast cancer?

42:09

Well, this is about two and a half years ago.

42:11

And we also then had to ask

42:13

where was the covid vaccine given this patient had a covid

42:16

vaccine three weeks earlier, one

42:19

of these lymph nodes was resected and it was reactive.

42:21

So this was path proven, uh, reactive, uh,

42:25

lymph adenitis from the covid vaccine.

42:28

And this is one where I completely messed up.

42:31

You know, this was a patient that I was told came in,

42:34

had a gloma tumor and apparently an

42:36

outside CT was called a gloma tumor.

42:38

So I remember looking at this next CT

42:41

and I said, well yeah, this looks like a gloma tumor to me,

42:43

it looks like it's hypervascular.

42:44

Then we got the MR and I completely botched it.

42:48

Anytime that you have a hypervascular lesion, anytime

42:52

that you have a gloma tumor greater than two to two

42:55

and a half centimeters, you should have multiple flow void.

42:58

So I had what was called a confirmation bias.

43:01

I tried to confirm what I was told and I go back

43:04

and I still kick myself

43:05

because you can see there are no flow voids.

43:08

And this turned out to be metastatic thyroid carcinoma.

43:11

So I show this to warn you about confirmation bias

43:14

and also warn you anytime

43:16

that you have a hypervascular lesion in the left neck,

43:19

and if you don't see those flow voids,

43:21

it's highly unlikely you're gonna have a paraganglioma.

43:25

And this was an example that you initial thought,

43:27

you may think that it's actually a lymph node,

43:30

but notice how this is located between the anterior

43:33

and the middle scanline muscles.

43:35

This is where the brachial plexus is,

43:37

and these are multiple neurofibromas involving

43:40

the brachial plexus.

43:41

So not everything

43:43

that looks like a lymph node is actually a lymph node.

43:45

And if you understand the anatomy,

43:47

you can make the correct diagnosis.

43:50

So the last thing that I'll end up with is, you know,

43:53

where do I even start?

43:54

You know, lymph nodes can be pretty complicated.

43:57

So you know, what's my approach?

43:59

So I'm just gonna give you my approach when I'm looking at a

44:04

head and neck ct, especially in patients with cancer.

44:07

So if I know that the patient has an oral tongue cancer,

44:10

the first thing that I wanna do is find the cancer

44:13

and find the side.

44:15

Once I identify the side, then I know that the majority

44:18

of the metastatic lymph nodes are gonna be on the

44:21

ipsilateral lymph nodes

44:23

and they're going to involve level one,

44:26

excuse me, level two.

44:27

So this oral tongue cancer typically involves level two on

44:31

the ipsilateral side.

44:34

Here's an example of a Fluor mouth carcinoma.

44:37

I, again, I find the side it's on,

44:39

it's in the floor of the mouth.

44:40

And then when you look at the lymph nodes

44:42

that are most likely gonna be involved

44:44

with a lateralized fluor mouth cancer,

44:46

it's gonna be level two and level one.

44:50

Similarly, this is a tongue-based cancer.

44:53

Here's a right-sided tongue-based cancer.

44:55

Now both nodal groups can be involved,

44:57

but again, a higher likelihood

44:59

that the ipsilateral level two lymph

45:01

nodes are gonna be involved.

45:04

And this is an example of a laryngeal carcinoma.

45:06

You sort of get where I'm going with this,

45:09

right-sided cancer here, the most likely group level

45:12

that's going to be involved is level two on the

45:15

ipsilateral side.

45:17

So what do we learn from this?

45:19

If you can understand this,

45:21

then you can understand the staging system

45:23

because an N zero disease means

45:26

that there's no regional metastases.

45:29

Now if you have N zero

45:31

and you go to N one, what do you think N one means?

45:35

Well, you probably figured out N one disease means

45:38

that there's a metastases in a single ipsilateral

45:42

ipsilateral lymph node that's less than three centimeters.

45:46

Now if you have an N one,

45:48

that means you have to have an N two.

45:51

So what do you think N two means?

45:54

Well if you have an, if this lymph node

45:57

that's less than three centimeter starts to get larger,

46:00

well then that's what's referred to as N two A.

46:04

You just take that same lymph node and it becomes larger.

46:08

Now what if you have this one lymph node

46:10

and it starts to recruit its friends on the

46:13

same side of the neck?

46:15

Well that is an N two B lymph node.

46:18

So now we're looking at multiple ipsilateral lymph nodes.

46:22

Now what if that lymph node becomes really popular

46:25

and he goes from one side of the street

46:26

to the opposite side of the street?

46:29

So this means that it's the contral nat lateral neck.

46:32

So when you look at N two C,

46:35

this means the contralateral neck.

46:37

And then finally, if that lymph node gets really,

46:40

really big greater than six centimeters,

46:43

now it becomes M three disease.

46:46

Now if you look real closely right here, I put ENE

46:51

in yellow, ENE means extra nodal extension.

46:55

So I think those of you know

46:56

that I've been on the staging system since

46:58

the fifth edition.

47:00

In the eighth edition for lymph nodes.

47:03

In patients that are HPV negative, this is all HPV negative.

47:07

We added this classification of extra nodal extension.

47:11

And what extra nodal extension is, is when the tumor extends

47:15

outside of the capsule.

47:17

Now, from a radiologist standpoint, we cannot

47:22

call extra nodal extension based on imaging alone.

47:25

Extra nodal extension is a clinical diagnosis.

47:29

So these lymph nodes tend to be larger

47:31

and they tend to be fixed, okay?

47:34

Now from our standpoint,

47:37

the radiological findings can be supportive,

47:41

but they're not definitive.

47:42

So the reason is, is

47:44

because if you have overaggressive radiologists like myself

47:47

that think they're better than they actually are,

47:50

I may see a lymph node that I think is one centimeter,

47:53

but with my eyes I can say, wait a minute,

47:55

I think I see some extra nodal extension.

47:58

Well, what we've inadvertently done is

48:01

that I could potentially upstage a lesion from N zero all

48:04

the way to N three B disease by calling something

48:08

by this extra nodal extension.

48:10

So in order to prevent this stage, cre,

48:14

extra nodal extension is a clinical diagnosis.

48:17

But on the other hand, radiology is confirm confirmatory.

48:23

So this lymph node staging is for HPV negative.

48:27

We all know that in the new staging system there's actually

48:31

HPV positive.

48:33

Now if you look at this, it's a lot more simpler.

48:36

So N zero is none, N one is less than six centimeters.

48:41

Remember back here that N one disease was less than three.

48:45

Well this is less than six centimeters for N two disease,

48:50

everything's less than six centimeters

48:52

and there's no separation between ipsilateral

48:55

or bilateral disease.

48:56

And N three is less than six centimeters.

48:59

Now what this reflects is the better overall prognosis

49:04

for HPV positive oral pharyngeal carcinomas.

49:08

So when we look at the overall survival of

49:13

HPV negative oral pharyngeal carcinomas,

49:17

if you look at the T stage

49:18

and the end stage, I wanna point your attention

49:21

to N two disease and N three disease.

49:24

Notice for N two disease it's four A,

49:28

and for N three it's four B.

49:29

This is pink and this is red. Red is usually bad, right?

49:33

So this is for HPV negative.

49:36

But when we look at HPV positive, look at N two

49:40

and N three, this is now stage two

49:43

and this is now stage three.

49:46

So the reason is, is

49:47

because overall HPV positive carcinomas tend

49:51

to be a better prognosis.

49:53

And the reason is based on the staging.

49:56

So if you look at this example on the bottom left,

49:59

here's a patient that has a metastatic lymph

50:02

node to the left neck.

50:03

And if you look real closely,

50:05

we can see it's irregular clinically this was fixed

50:08

to the neck and we can suggest it

50:10

because we can see this irregular shaggy margin

50:13

and it's completely invading the muscle.

50:15

So this was extracapsular penetration.

50:19

Now if this was HPV negative,

50:21

this would be N three B disease.

50:23

But because this is less than six centimeters

50:26

and only involving one side of the neck,

50:29

this is actually N one disease.

50:31

And this is why this lymph node approach

50:34

and the overall better prognosis is associated

50:37

with a better prognosis in HPV positive disease.

50:42

So in summary, what we've done over the last 15 minutes is

50:46

that we've gone over the lymph nodes of the head and neck.

50:49

So for me, the take home message is,

50:53

I know you're not gonna remember everything I say, you know,

50:55

come back to a modality

50:56

and listen to lecture over and over again.

50:59

But what I wanna leave you with is this.

51:01

Remember the level one lymph nodes are these lymph nodes

51:04

that are below your chin.

51:06

So remember your dog or your cat

51:08

or whoever, um, if you've been palpating their chin,

51:11

you've been examining their level one lymph nodes.

51:14

The levels 2, 3, 4,

51:15

and five lymph nodes are like a string of pearls.

51:19

The next thing is that when you're evaluating patients

51:22

with head and neck cancer, remember to begin

51:25

to look at the ipsilateral neck and look at level two.

51:28

Now you have to look at all of the lymph nodes,

51:30

but the majority of lymph nodes are gonna metastasize

51:33

to the level two lymph nodes on the ipsilateral side.

51:37

And that's exactly where my eye goes

51:39

to when I'm first evaluating these patients.

51:42

And finally, remember these retro pharyngeal lymph nodes,

51:46

these are sometimes these hidden lymph nodes

51:49

and remember, these are our lymph nodes

51:51

because there's no way the surgeons will be able

51:53

to palpate these lymph nodes

51:55

and make they make a huge difference in

51:57

how these patients are treated.

51:59

So thank you very much for your attention.

52:01

I think we have about 10 minutes.

52:03

I can probably go a few minutes over if we have time.

52:05

But again, thank you very much for your attention.

52:10

Thank you so much for your lecture, Dr.

52:11

McCury at this time, um, if you'd like to pop open that q

52:15

and a feature at the top of your screen,

52:19

we've got a couple questions in there

52:22

and if anyone else wants to submit questions, please be sure

52:25

to use that q and a feature.

52:30

Okay. Um, the first question I have is, um, it says,

52:32

have you seen int glandular lymph nodes

52:34

and submandibular glands?

52:36

Why not in reference to parotid? No.

52:39

Um, so have not seen specifically,

52:44

um, metastatic lymph nodes in the submandibular glands.

52:48

And the reason is the following is

52:50

that in the parotid glands there's actually four groups

52:54

of lymph nodes in the parotid glands

52:55

and they're located in the pretracheal area

52:59

below the capsule, along the facial nerve

53:02

and then also when the tail of the parid glands.

53:05

So that's why you can see intra parid lymph nodes now, uh,

53:09

int glandular submandibular glands.

53:11

It's very rare, if anything, to see

53:15

submandibular lymph nodes.

53:16

So it's very rare. Occasionally what I will see

53:19

are level one lymph nodes sometime extend into

53:22

and involve the subandi glands.

53:25

Um, that's also why Han's tumors are very unusual

53:29

to rise in the submandibular glands

53:31

because Han's tumors,

53:32

the other name are cyst adenoma lymphoma

53:36

and they arise within the lymphoid tissues.

53:39

So that's why we see more Han's tumors in parotid glands.

53:43

And we don't see Wharton's tumors in general in

53:46

submandibular glands

53:47

because the paucity of lymphatic tissue.

53:50

So hopefully, um, that answered your question.

53:54

Um, medial versus lateral retropharyngeal lymph nodes, uh,

53:58

is there a differentiation?

54:00

Um, and the answer is yes.

54:02

Now I'll tell you that, um, if you, uh,

54:07

you should be able to see, you can see my screen right

54:09

Ashley, I hope you can hear me.

54:10

Is that right? Yep.

54:11

Um, yeah, so this group

54:13

of lymph nodes is the lateral retro pharyngeal lymph node

54:16

and this is the medial retro pharyngeal lymph node.

54:19

Now this is a very, um, point, uh,

54:22

important point when it comes to

54:25

treating patients with head and neck cancer.

54:28

When we are born, we have direct communications

54:30

with the lateral and the medial retro

54:32

pharyngeal lymph nodes.

54:34

In adults, the majority of lymph node metastases are going

54:38

to involve the lateral retro pharyngeal lymph nodes.

54:42

And the question is, why does that happen?

54:45

Well, some people feel it happens is that as we are kids,

54:49

we get a lot of throat infections.

54:51

And one of the theories is, is that

54:53

because of all the throat infections we get, we tend

54:57

to fibrosis off these lymph channels that go

55:01

to the medial retro pharyngeal lymph nodes.

55:03

So as we get older, the majority of spread goes

55:07

to the lateral retro pharyngeal lymph

55:09

nodes and not the medial.

55:11

On rare occasions I can see medial retropharyngeal lymph

55:15

nodes, which are gonna be just off midline

55:18

behind the pharynx.

55:20

But it's actually important from a clinical standpoint

55:23

because a lot of the radiation oncologists know as an adult,

55:28

the majority of lymph nodes are gonna involve the lateral

55:31

retropharyngeal lymph nodes.

55:32

So oftentimes they don't treat the medial group.

55:35

And the reason they don't do that is

55:37

because if they treat this, then they're going

55:39

to give a high dose radiation

55:41

to the superior constrictor muscle

55:44

and oftentimes these patients will have

55:45

difficulty swallowing.

55:47

So your question isn't a very important question

55:50

because it actually affects how these patients are treated.

55:54

So in the majority of the adult adults,

55:56

we're gonna see involvement

55:57

of the retro pharyngeal lymph noss.

56:01

Um, the next one is what is the cutoff size for head

56:04

and neck lymph nodes and head and neck cancer?

56:06

Uh, I think I mentioned that in the talk it's, um,

56:10

10 millimeters for levels 1, 3, 4 and five

56:15

and 1.5 centimeters for level, um, for level two.

56:19

So, you know, I'll refer you back to the, the talk again,

56:22

'cause I, I think I had a slide on that one.

56:25

Um, is it feasible to combine nodal groups in the head

56:29

and neck to the chest and the lung?

56:32

Um, so I

56:36

don't know about the, how the numbering system in the chest

56:40

and the lung happened.

56:41

Um, I can tell you that that level seven lymph node, um,

56:46

is actually a mediastinal lymph node.

56:48

So I would say there's that overlap,

56:51

but, um, I don't know specifically, um,

56:54

how the numbering system is done in the chest.

56:56

So I would have to refer to my, um,

56:59

other colleagues about that.

57:02

Um, good question. What about the matted

57:05

and conglomerate lymph nodes?

57:07

How to check the size?

57:08

That's a really, really good question.

57:10

Um, I can tell you how I do this.

57:13

Um, if I see matted lymph nodes,

57:15

I will measure in the axial plane.

57:19

Uh, and if it's greater than 1.5 centimeters, then

57:22

what I would do is I would

57:24

then take a different measurement either in the para sagal

57:29

plane or an oblique plane and take the largest measurement.

57:33

So for me, what I do

57:35

is my first measurement is actually in the axial plane.

57:39

If it's greater than 1.5 centimeters,

57:41

then I know it's gonna be metastatic.

57:43

So that takes me to N one disease.

57:46

But then what I do is I take a separate measurement in the

57:49

oblique planes and then based on that measurement

57:52

that will tell me whether I'm dealing with N two

57:55

or N three disease based on that.

57:58

So that's what I would recommend about the Matt

58:01

or the conglomerate lymph node.

58:02

It's a very interesting question,

58:05

but that's kind of uh, my approach I'm,

58:07

what I'm doing is looking for that largest measurement

58:10

for the final staging.

58:13

Um, can thyroid malignancy present with normal

58:18

mildly bunky thyroid or just lymph adenopathy?

58:22

Um, I just got this,

58:24

that's my long ca exam case in boards in India.

58:27

Well, I hope you're past your board, so good luck with that.

58:29

Um, uh, yeah, so thyroid malignancy can present

58:34

with bulky thyroid gland.

58:36

The thing about thyroid malignancy is, I think I showed you

58:40

that one case that I missed that had

58:42

that big hypervascular thyroid lymph node

58:45

or that thyroid lymph node.

58:47

Remember the one that I showed you

58:49

that was actually a clinically occult thyroid carcinoma?

58:53

So I looked at the thyroid gland,

58:55

even in retrospectoscope I couldn't see anything.

58:59

So sometimes thyroid cancers can present

59:02

as clinically occult lesions in the thyroid gland

59:05

and they just present as bulky lymph nodes

59:07

and unfortunately I went down the tubes on that one.

59:09

So again, anytime that you see, um, metastases

59:13

that are hypervascular, anytime that you see them

59:16

that are calcified, anytime that you see cystic,

59:20

anytime you see anything in the trache esophageal groove

59:23

or even the retro pharyngeal node, think

59:26

of potentially thyroid carcinoma even if you don't see

59:30

anything in the thyroid gland.

59:34

Um, so case of parotid lesion

59:37

with a six millimeter retro pharyngeal lymph

59:39

node, what would I say?

59:41

Great question. So in general, um,

59:46

I would have to first know what the parotid lesion is.

59:49

I mean, the majority of parotid lesions are benign.

59:52

Um, it would be unusual to have, uh,

59:56

primary echelon drainage between the parotid gland

60:00

and the retro pharyngeal lymph node.

60:02

So I would probably think

60:04

that the retro pharyngeal lymph node is an incidental

60:07

finding in the patient of the parotid lesion.

60:10

Even if, um, uh, I would just stop there, uh, I think, uh,

60:15

especially if the parotid lesion was benign,

60:17

that's why I wanted to say, so I would say

60:20

that the six mil mil,

60:22

six millimeter lymph node is probably just, uh,

60:25

incidental finding, um, measurement

60:29

of level one

60:30

and other levels different as they are oriented.

60:33

Could you demonstrate how to measure them again? Uh, sure.

60:36

Let me see if I can go back to that one.

60:39

So here's our level one lymph node here,

60:43

and then there's our level two lymph node here.

60:45

So for the level one lymph nodes,

60:47

it's basically the same approach.

60:49

I mean, so if I was measuring, um,

60:52

this level one lymph node here,

60:54

so here's a level one lymph node here,

60:56

I would measure it from here to here.

60:58

So longest dimension.

60:59

Um, and I think there's one more,

61:01

if I go back really quickly to

61:05

this level one lymph node.

61:06

So here, okay, so here's a level one lymph node here, right?

61:09

So if I was measuring this level one lymph node,

61:11

I would just make it from here and then go back to there.

61:14

So again, similar to what we did

61:16

before, just take the longest axial dimension.

61:20

Yeah, I'm so glad everyone is still with me too.

61:22

This is awesome. Let's see.

61:24

Oh, thank you, uh, very much for that.

61:26

Let's see, I might, we're doing q and a right Ash?

61:29

Yes, let's see. That's supposed to check. Okay.

61:31

Um, thank you Scott. Uh, let's see.

61:36

Are occipital lymph nodes viewed as low?

61:38

That's a really good question. No, they're not.

61:40

They're actually a separate group

61:42

of lymph nodes are actually referred to as suboccipital

61:45

or posterior auricular lymph nodes in general.

61:48

So they're a separate group from that

61:50

and I tend to do 10 millimeters for that.

61:55

Um, so two more.

61:56

Sometimes we find possibly level five

61:58

lymph nodes pretty low.

62:01

Um, yeah, so to chin moist question,

62:05

I just call these occipital lymph nodes

62:07

and I'll probably use a one centimeter cutoff as well too.

62:10

They haven't been well described,

62:12

but I'll use those as um, suboccipital lymph notes.

62:16

Um, yeah, significance

62:18

of larger cranial coad dimension versus ap.

62:21

Should we report to discrepancy? Great question.

62:24

I don't Alex. Um, so what I end up doing is this, um,

62:28

if you look at this image on the left, I will measure, um,

62:32

let's see, go back here.

62:35

I will measure my lymph node like this

62:36

to determine whether it's positive or negative.

62:39

And then if it's greater than 1.5 centimeters

62:42

or if I actually think it's metastatic,

62:45

then I will measure the second plane in a different

62:47

dimension to see whether it's greater than three centimeters

62:51

to upstage it to end two disease.

62:53

I do that because that's the way the surgeons,

62:56

you know, actually palpated.

62:58

Um, and then one more. Ashley, is that what you want?

63:01

Let's see. Yeah, that sounds good. Yeah.

63:04

Um, so, uh, for all level measurements

63:08

to be done, um, let's see,

63:11

for all level measurement done in axial

63:13

and biggest dimension, so yeah, axial plane,

63:17

largest dimension, um,

63:20

if I see a level two lymph node with cutaneous fistula,

63:23

can I suggest tuberculosis?

63:25

Um, yes, if you have, if you're in an endemic area

63:28

and the patient doesn't have a primary uh, tumor, um,

63:32

if you're an endemic area, I think that's,

63:34

uh, very reasonable.

63:37

Um, and uh, should that's it

63:41

or should we do one more? Actually, I'll leave it up

63:43

To you. Find how about

63:44

you find your favorite question

63:45

and we'll end on that one.

63:48

Um, let's see.

63:49

Um, is there a different measurement between lymph nodes,

63:54

between CT and mr?

63:55

The answer is no. That that was easy.

63:57

Noted that, um, is there a sub categorization

64:00

for levels four and, and level five?

64:03

Um, yes, there is, um, uh, differentiate

64:07

between SCL and these.

64:08

Like I say, it's, it's kind of hard.

64:10

Um, that's probably a lecture unto itself.

64:14

So why don't wanna go ahead and stop there.

64:15

Otherwise, I'll talk forever on this

64:17

topic 'cause I love it so much.

64:20

Well, thank you so much for, uh, coming

64:22

and doing this lecture, uh,

64:23

very clearly there is a lot of interest in this.

64:25

We'll have to do a separate q and a session

64:26

or have you back for part two.

64:28

So thank you so much Dr. McCury.

64:30

Okay, thank you very much everyone.

64:33

Yeah, and thank you everyone else

64:34

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64:36

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