Upcoming Events
Log In
Pricing
Free Trial

Wk 2, Case 5 - Review

HIDE
PrevNext

0:00

Localized swelling mass in the right neck.

0:05

So you had a MR of this case. Again, um,

0:10

we can use the stir to identify the

0:15

pathology, and

0:20

here we are at the nasopharyngeal level,

0:22

and then we come down to the soft palate level. Here's our soft palate,

0:26

and we're at the oral pharyngeal level.

0:29

And here we have our lesion that is extending into the,

0:35

uh, right side of the neck. And it's pretty clear that there's once again,

0:39

extra nodal extension.

0:42

We have multiple lesions here. That's a nodal conglomerate. Um,

0:47

one of the questions on this case, which I think is valid is,

0:50

is this all contiguous with the lesion over here

0:55

in the tonsil? And the other valid question is,

1:00

um, it sure looks like the pharyngeal mucosa, uh,

1:04

the pharyngeal musculature, which is a dark thing,

1:07

is being displaced inward by this mass.

1:11

How do we know that this is primarily in the tonsil as opposed to

1:16

outside the tonsil? Uh, it is centered on the tonsil here.

1:23

Um, so, uh, all of which I think are, are valid questions.

1:28

When you see this little muscular thing,

1:30

the problem is that the tonsil, um,

1:34

obviously is the lymphoid tissue,

1:36

and it may not be on the mucosa surface.

1:41

Uh, it may be in the,

1:44

starting in the crypts of the tonsil where it looks like a submucosal mass.

1:49

And so, although tonsil is part of the oral pharynx,

1:52

which is part of the aero digestive system, uh,

1:55

it is a site where the growth may be quickly

2:01

submucosal and into the soft tissues of the

2:05

neck. Um, on this, uh,

2:10

stir image, we do get the sense that there are multiple nodules here,

2:14

more likely to represent lymphadenopathy than just a tonsil

2:19

cancer gone wild that's growing into the neck,

2:23

even as far down here as the, um, thyroid cartilage.

2:28

So

2:31

my interpretation of this would be that there's a submucosal mass

2:36

at the level of the tonsil with associated contiguous

2:42

multiple lymph nodes with extra nodal extension.

2:45

So let's look at it on the T one way scan and see how this helps us.

2:50

So I'm gonna, all right, it's a little bit brighter that way.

2:55

So clearly there

2:58

Is a component of this that's outside the, the mucosal surface,

3:03

but as you get down to the tonsil level, that's harder to say.

3:08

And we recognize that tonsil cancer can grow in this fashion

3:13

as it grows laterally. Here we wanna look at a couple of things.

3:18

We wanna look at the prevertebral musculature,

3:21

which is the longest coi, longest capita muscle complex,

3:25

because if this tumor grows into the prevertebral musculature,

3:30

it makes it more likely to be unresectable disease.

3:34

And a T four cancer prevertebral or skull base involvement is

3:39

going to be a T four B cancer.

3:41

So when we see this flattening of the muscle,

3:45

we wanna go back to the stir and say,

3:48

is that muscle bright to suggest that it's been infiltrated?

3:53

It doesn't look like here's our normal musculature,

3:56

and here it is flattened by the lesion. So it's,

3:59

it's opposed to it, but not infiltrating it.

4:04

And the other way we would look at that would be with the post gad to see

4:08

whether we see asymmetric contrast enhancement of that musculature

4:13

right here. You might be worried about that,

4:21

but it didn't correspond to the, uh, stir as far as,

4:26

so we're right at the uvula, so let's go to the uvula.

4:30

Not really seeing that, but that,

4:32

that's an issue that would have to be addressed because

4:36

fixation to the prevertebral musculature makes things unresectable.

4:43

The other thing that we wanna look at is the relationship of this to the

4:48

vasculature,

4:48

because infiltration in and around the carotid artery with

4:53

fixation also makes it unresectable disease and, um,

4:59

T four B disease. So in this instance,

5:02

those vessels fortunately are displaced laterally,

5:05

but they're not encased by the tumor. It is going,

5:10

you know, into the carotid space,

5:12

but it's not surrounding the carotid artery.

5:15

The next thing lower down that we wanna look at is,

5:19

and we're pretty far away from it, is the scaling musculature.

5:21

This is the anterior scaling behind the anterior scaling muscle is the brachial

5:25

plexus tumor into the brachial plexus also becomes unresectable.

5:29

We're pretty far away from that here.

5:31

We can see pretty clearly that there's a retropharyngeal lymph node.

5:35

So that will help us to say that this is not all continuous tumor,

5:39

that this is lymphadenopathy. So,

5:44

um, let's go back to the, um,

5:48

and look at t staging of oropharyngeal cancer,

5:52

which is this tonsil. So the key

5:56

Here is that there's two different staging. One is for

6:02

H P V positive oropharyngeal cancer,

6:07

two centimeters, two to four centimeters greater than four sonometers,

6:11

and then infiltration of soft tissues, larynx, muscle,

6:16

et cetera,

6:17

versus those T oropharyngeal cancers,

6:23

which are not H P V positive.

6:26

The reason why we separate these is because H P V positive cancers are very

6:32

responsive to radiation and chemotherapy and are curable

6:37

even when they're in the T four stage. However, if it's H P V negative,

6:42

and this is the staging for H P V negative, you can see that

6:47

T four B is very advanced, usually unresectable disease, skull base involvement,

6:52

internal carat artery encasement, lateral nasopharyngeal involvement,

6:56

all these things make it T four B and skull base.

6:59

We would also include infiltration of the longest coline long ca capus muscle

7:03

complex. So, um, we would measure this,

7:08

it looks to mean like it's gonna measure over four centimeters in size.

7:11

So we probably have a T three cancer.

7:14

We would then go to our end staging and look

7:19

at the lymph nodes and there's multiple ipsilateral lymph nodes

7:24

with extra nodal extension. So that would be N three B disease

7:31

and, um, advanced cancer. So the,

7:36

the pertinent findings here are what's it doing to the skull base

7:41

prevertebral musculature, what's it doing to the carotid artery? Um,

7:47

and with the lymph nodes, again,

7:50

are the lymph nodes infiltrating around the carotid artery?

7:52

Is there extra nodal extension, et cetera? Remember again,

7:55

the extra nodal extension is a pathologic diagnosis,

7:58

but we usually can imply it with our imaging findings.

8:03

Let's go back to the images and just see whether there was anything else worth

8:08

pointing out in this case. Um,

8:11

so here is our OID musculature.

8:15

We wanna look at that once again on our stir imaging

8:21

to see whether those muscles are infiltrated.

8:28

So it looks like it's up to the muscle,

8:30

but not infiltrating the muscle important negative

8:36

and no bone involvement. So for bone involvement,

8:40

I prefer to look at the T one wave scan because usually you're able to see the

8:43

bone marrow bright signal as well as the cortical very dark signal

8:48

and we're not seeing anything there.

8:52

No contralateral lymphadenopathy.

8:55

So again, best to look for that with our

9:00

stir image that shows whether or not, um, we have right lymph node.

9:06

Here's the CT scan. Again, kinda looks like everything's all contiguous.

9:11

We see that there is necrosis in these small lymph nodes.

9:14

So there is lymphadenopathy, it's a conglomerate,

9:17

massive of lymph nodes here with necrosis.

9:21

And this fuzzy fat defining sort of the extracapsular

9:27

or extra nodal extension. There's some edema in the, uh,

9:33

retro pharyngeal space here is that little retropharyngeal lymph node.

9:37

And here we're a little bit,

9:39

looks a little bit more primary tonsil cancer.

9:45

Um,

9:47

some people asked about whether this could be a schwannoma or a, um,

9:53

paraganglioma.

9:54

The argument against paraganglioma is it's not really that vasculature,

9:58

no big vessels,

9:59

and it's coming into the mucosal space here,

10:05

um, in a way that is, would be unusual for any type of paraganglioma.

10:09

For a schwannoma. Again, we have these necrotic lymph nodes that are, uh,

10:14

evident. Um, and that would,

10:18

for a benign tumor would be unusual.

Report

Patient History
Localized swelling. Mass in right neck.

Findings
Pre- and postcontrast MR was performed of the neck. The study is abnormal. There is a large mass involving the right palatine tonsil which could be submucosal and medially displaced in the right tonsil. The lesion extends laterally and involves the right parapharyngeal space. The lesion extends deeply and is in close proximity to the right paraspinal musculature. The superior aspect of the tumor extends submucosally to the level of the right nasopharynx with extension into the region of the right torus tubarius. No definite evidence of skull base involvement is seen, although it does extend in close proximity to the inferior skull base. Inferiorly, the lesion extends into the soft tissues of the neck and extends inferiorly to the level of the right pharyngoepiglottic fold. There is anterior displacement of the right submandibular gland with asymmetric enhancement which could be due to adjacent sialadenitis.

There is some edema and enhancement right paraspinal musculature adjacent to the mass which could be due to deep muscle involvement. However, these findings should be correlated with clinical signs of fixation for accurate staging.

There are some enlarged likely metastatic lymph nodes involving right level 2. However, on the MR, this appears to be a conglomerate mass that involves the right tonsil and extends laterally with direct extension into the right neck. Given the patient's age, this likely represents squamous cell carcinoma involving the right tonsil (likely HPV positive) versus lymphoma. Other mesenchymal malignant neoplasms are less likely. CT of the neck may be helpful to better define the lesion and assess for lymph node involvement.

Conclusions
1. Large mass involving the right visceral space extending laterally into the parapharyngeal space and right neck which is likely due to squamous cell carcinoma of the tonsil (likely HPV positive) versus lymphoma.
2. There is some edema and enhancement directly adjacent to the right paraspinal musculature suggesting deep muscle involvement. These findings should be correlated with clinical signs of fixation.

Case Discussion

Faculty

David M Yousem, MD, MBA

Professor of Radiology, Vice Chairman and Associate Dean

Johns Hopkins University

Suresh K Mukherji, MD, FACR, MBA

Clinical Professor, University of Illinois & Rutgers University. Faculty, Michigan State University. Director Head & Neck Radiology, ProScan Imaging

Tags

Neuroradiology

MRI

Head and Neck

CT