0:00

Well, good afternoon, good morning, or good evening, wherever you are.

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Thank you very much for joining us. Uh,

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I will be talking about molecular PET in head and neck oncology.

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Those are my disclosures, but nothing relevant to the topic we'll discuss here.

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We will talk about the major differences between molecular PET and radiology,

0:18

and we will see the proven value of FDG PET in head and neck oncology

0:23

and the pending value of Durate PET in Head and Neck Oncology.

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Instead of providing you the sensitivity and specificity analysis from the

0:32

literature, I will be very practical and I will share you cases.

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All of them are my own cases from NYU,

0:40

the institution that I work right now,

0:42

because I want to show the real value of how practical the molecular pets

0:47

could be in the real world, except the last case, and we will see.

0:50

So I'm going to stop my video so that we can all focus on the images.

0:57

Let's start with the differences. What's the biggest difference between,

1:00

between anatomic versus PET imaging?

1:03

That's the basic question between radiology and molecular nuclear medicine, uh,

1:08

practices in radiology, as we can see here, we have an external source,

1:12

whether it's a CT or MRI,

1:15

and it is an organ based imaging, whether you scan the brain, head,

1:19

and neck or part of the body, it's organ based.

1:22

So the biggest amount of data that you can collect is going to give you the

1:27

information about the local tea and no and staging as opposed to

1:32

pets. It's an emission scan.

1:34

We inject small amount of minor amount of, uh,

1:38

radiopharmaceutical, and then the body becomes the, uh, source of average,

1:44

uh, signal body becomes the, uh, signal emr,

1:49

and the pet scanner collects the signal from the patient's body.

1:52

That is a product of the inherent physiologic or,

1:57

um, pathologic, uh, states. So the difference is, again,

2:02

anatomic organ-based, and we have,

2:06

it's a transmission scan because we have an external source as opposed to pets

2:10

molecule. It's an, um,

2:13

functional imaging because we inject the patient and then after a while we image

2:18

the patient as a whole,

2:19

the entire body to see the physiologic as well as the pathologic processes.

2:25

And one of the fundamental differences, aside from the tech, uh,

2:29

techniques or technical equipment that we use,

2:32

is the pet tracers versus the gadolinium. Because in CT or MRI,

2:37

we use contrast and mostly in, um, this is the,

2:41

the example shown here is an, um, blood vessel that shows how the contrast,

2:47

uh, enhancement happens as opposed to the pet molecular pet, um,

2:52

radio, uh, radiopharmaceuticals and the molecules at the top. So let's focus on,

2:57

um, the galium first on M marsh, which the same applies to the iodine.

3:02

You do have either increased number of vessels within the, um,

3:06

within the mass or wherever the disease is.

3:09

And this increased number of vessels are not healthy vessels. They are leaky,

3:14

as you can see here,

3:15

and they let either the iodine or the gadolinium to leak through the vessels,

3:19

and that creates your enhancement and the recognition of the mass or lesions

3:24

as opposed. And this is a very passive process.

3:27

There is nothing specific to the type of the disease. Everything can enhance,

3:31

right? As opposed to the pets, it is as specific as we can get.

3:37

The most commonly used radiopharmaceutical is FDG. As you can see,

3:40

it's a glute transporter, uh,

3:44

specific evaluation of the diseases. And the second most common clinically used,

3:49

uh, tracer we are talking about head and neck again, is do rotate pet.

3:52

And that is not specific,

3:54

but highly selective to somatostatin receptor type two.

3:58

And both are localized at the cell membrane.

4:01

When a patient receives the radiopharmaceutical, as you can see here,

4:04

after they are, um, um, after they are out, they are,

4:09

uh, transferred into the interstitial space.

4:13

They interaction with the disease states is through transporters or

4:17

receptors, which is highly or more, uh,

4:21

highly selective and more specific compared to gadolinium.

4:24

It's not a passive evaluation of what is going on in the patient's body,

4:28

but it's more active evaluation of what functionally is going on in the

4:32

patient's body. And once again, tracer uptake is not equal to enhancement.

4:38

And after that, um,

4:39

this is the laundry list of pet tracers that we use either for clinic or for

4:44

our research purposes. But I will show you the prudent value of glucose

4:50

analog, which is the f pg pet, uh, more commonly known,

4:54

known as well as the durate pet. Uh,

4:57

that is an receptor as you can see here, durate peptide, uh, receptor imaging.

5:03

And this is,

5:04

I just want to put the name here so that we all become familiar.

5:09

I think that is what the feature lies in. Uh, some, uh,

5:13

certain disease states but not, uh,

5:15

well proven for the headache yet as much as FDG and all other

5:20

imaging, um, tracers that we have so far are focusing on the cells,

5:25

specifically the cancer cells. This tracer, namely api,

5:29

the fibroblast activation protein inhibitor, uh,

5:33

is focusing on the tumor microenvironment.

5:35

And now we know that tumor microenvironment is one of the major drivers

5:40

of, uh, treatment response or developing treatments, uh,

5:44

resistance to, uh, certain, uh, immunotherapy agents.

5:49

So why do we care, right? Because why do we wanna have more and more data

5:55

wouldn't be head next CT or MRP enough, uh, for providing the patient,

6:01

uh, the appropriate prognostic stage work, right?

6:04

The only way we can acquire this complimentary evaluation after primary

6:09

nodal and nodal disease evaluation by the CT or MRI is PET

6:14

ct. We need PET CT to be able to talk about the, uh,

6:18

metastatic disease evaluation and provide the prognostic accurate

6:23

prognostic stage group so that this data becomes the elements of

6:28

AJCC staging, uh,

6:30

which is the current army uses AJCC eight.

6:33

And that data becomes the treatment algorithm

6:38

elements for the standard of care,

6:40

which is established by the NCCN guidelines,

6:43

national Comprehensive Cancer Network.

6:45

So our reports feed AJCC staging for prognostic stage group.

6:50

It feeds the NCCN, um,

6:53

evaluation or the guidelines for the patient to receive the standard of care.

6:58

As much as we don't want our patients to be undertreated,

7:01

we don't want to be overtreated either.

7:04

This is the physiologic distribution, uh,

7:06

of the most commonly used PET tracers that I will be, um, talking about.

7:12

This is a normal ATE pet and that is a normal FDG pet.

7:18

If you don't know anything about these, the most, uh,

7:22

significant, the, the, the,

7:25

the most significant difference between these two is if you don't wanna,

7:29

if you don't recognize or don't want to recognize anything.

7:31

But please make sure that you can see this cortical brain cortical activity on

7:36

this FDG pet. This is the biggest difference for head on neck radiologists.

7:41

That FDG will have intense optic at the uh,

7:46

brain cortex.

7:47

It will make our job very difficult to differentiate what is going on

7:52

at the skull base for masses close to the skull base as opposed to

7:58

ate pet, which is used for um, certain disease, uh, processes.

8:03

You can't see that the brain has no uptake. Background is zero.

8:07

Anything at the skull base or in the cavernous sinus or in the medical scape

8:11

anywhere in the skull within the intracranial compartment

8:17

will light up like a light bulb.

8:19

So recognizing anything at the skull base for certain diseases like mening

8:24

para gangs or anesthesia neuroblastoma is going to be way easier

8:29

than trying to dissect what is going on at the brain skull base interface.

8:34

One other, uh, for this is more, um, general information for,

8:39

um, the audience who reads PET CT or MRI as a part of the data practice.

8:45

Physiologic distribution is quite different for dotatate.

8:48

Physiologically pituitary is one of the uptake sites as opposed to

8:53

FDG.

8:53

There is no pituitary uptake or there should be no pituitary uptake do shows

8:58

uptake in the major sary glands and spleen and the

9:03

kidney cortex are the hottest organs so to say.

9:07

And you can see that liver has, uh,

9:09

mild to moderate activity as well on the FDG PET is.

9:12

You can see here liver and spleen are almost equally um,

9:17

um, mildly positive, but the uh,

9:21

order of physiologic uptake should always be liver higher than the spleen.

9:26

Sometimes could be equal, but the spleen should never be higher than the liver.

9:31

And as you can see for the chest nodules, both have um,

9:36

uh, advantage because the background is zero.

9:41

So let's talk about the cases we're going to start. Uh,

9:45

the rest of the talk will be full of cases and um,

9:49

we will start with the FDG PET and let's remind ourselves

9:54

FDG pet, as you can see here,

9:57

is a highly sensitive radiopharmaceutical

10:03

identifying metabolically active disease states going through that transporters,

10:07

the good transporters after the transportation into the intracellular

10:11

compartment, it stops there,

10:13

doesn't get further metabolized and shows us what is going on

10:17

intracellularly. Our first case is a nasopharynx case.

10:22

So do we need AFDG PET CT or MRI for nasopharynx, right?

10:29

Probably not so much for the local disease,

10:31

but definitely for the nodal and distant metastases.

10:34

Let's read the local disease here together. Top is the, uh, top row is the pet,

10:39

MRI,

10:40

bottom is the PET ct and this will be pretty much the same for the rest

10:45

of the uh, FDG PET images whenever there is PET MRI available.

10:49

I try to um,

10:51

add representative images here because I think for head on neck, uh,

10:55

oncology PET MRI is incur is in uh,

10:59

incomparably better compared to the PET ct.

11:02

So we have a mass at the right nasal pharynx directly infiltrating the skull

11:06

base. As you can see here on ct, it's not that easy to see,

11:11

but most of the time when you do PET ct, um,

11:14

you already have an or you will have an MRI anyway, uh, complimentary. So,

11:19

but if you can do both,

11:21

why not doing it both right at the same time simultaneously?

11:24

So we have a nasopharynx mass,

11:27

it's already infiltrating the skull base and extending into the intracranial

11:31

compartment, right? We are looking at this direct infiltration and it is uh,

11:36

almost extending to the uh, micro scale on the right side,

11:39

but definitely into the camera sinus. And it has,

11:43

when you look at the axial uh cuts, there is elements of um,

11:48

peral spread.

11:50

So when we look at the same we mass and how much it

11:55

extends, right, colvis,

11:57

pru apex are infiltrated and that is corresponding to the FDG

12:02

AVID component.

12:04

But look how CT is helping us understanding the CLIVAL and P two

12:09

apex and sphenoid bone erosion.

12:11

So CT and MR do not compete with each other. They're definitely complimentary.

12:17

So why didn't we do the pet, right or what are we gaining from pets?

12:23

Local disease evaluation as accurate as it can get with the MR or the ct,

12:27

the nodal disease evaluation is always cumbersome. As you can see here.

12:31

There are this insignificant looking right uh,

12:34

cervical lymph nodes deep in the neck, right? Uh,

12:37

those are probably level two B.

12:40

And what we see here is there is FDG optic, even if it's mild,

12:44

it's still higher than the background and those are the only two

12:49

metabolic active lymph nodes ips lateral to the nasopharynx mass.

12:54

So when we look at this whole body pictures next to each other is you can see

12:59

the nasopharynx nasopharynx or lateral projection.

13:03

It's pretty FDG AVID and these two lymph nodes, no matter how small,

13:07

no matter how insignificant they have looked on CT or MRI,

13:11

they are FDG positive as well. So F dg,

13:14

F dgs or F dg PET contribution is this patient already has N one disease

13:19

but nothing as distant metastasis.

13:22

Another one MRI is already telling us, right,

13:25

prevertebral muscles are infiltrated.

13:28

You can beautifully see on this post contrast TM automated image prevertebral

13:32

muscles are gone, but it's still um, uh, you know, it's,

13:38

it's still uh,

13:40

debatable whether the per range of fats on the right side is infiltrated or not.

13:45

That's a beautiful MRI scan. But if you don't have that information,

13:49

the CT is definitely not going to be that much helpful because on CT you are

13:53

looking at the BLE of enhancing mass most of the time.

13:57

So again,

13:58

these arrows to show you the pre retrievable muscle infiltration and

14:03

uh, how MRI can bet, uh, perform better than the uh, ct.

14:09

But why we do, why we really do or why we really need uh,

14:12

FDG PET here is to evaluate the nodal disease. As you can see here,

14:16

dental artifact is killing our image quality on mr not that much.

14:22

And we can easily see this right rangel, if not on ct,

14:26

PEP is telling us where it is, but we cannot really measure it on the ct.

14:31

And for nodal staging, uh, six centimeters, uh,

14:35

is the magic number anything higher or, uh,

14:37

below the six centimeter changes your staging, but for accurate measurement, um,

14:42

purposes, MRI is definitely doing a way better job than the ct.

14:46

And you can see MRI is clearly showing us or PET MRI this metabolic

14:51

niac,

14:52

the right spread tr andal lymph node and okay,

14:57

sorry. And this one, why did so the same case, uh, why did we do the FDG pet,

15:02

right? Yes,

15:03

right-sided nasopharynx no matter how a small but locally invasive or

15:07

infiltrative, it looked right, lymph apathy, right retro lymph node.

15:12

But FDG PET is the only way to be able to identify this contralateral lymph

15:16

node. No matter how small it is.

15:18

It's f DG positive FNA proven squamous cell cancer metastasis

15:23

upstages, the patient's noal evaluation.

15:25

So FDG PET is helpful in understanding what is going on in

15:30

the unexpected uh, noodle sites.

15:35

This looks a very benign mass, right? I think we all agree, uh,

15:39

it almost looks like just regular adenoid hypertrophy in any, um, adult,

15:45

but unfortunately you can't see this bulging asymmetric to the right

15:50

of Medline, right? This soft tissue fullness and is still confined to the

15:55

nasopharyngeal uh, compartment. The mucosal space,

15:58

what makes this abnormal is these lymph nodes,

16:01

bilateral lymph nodes and that was the patient's presenting, um, symptom left,

16:06

left-sided lymph pathy, I mean left-sided mass.

16:10

So when you have this level two lymph nodes that are already

16:15

cystic or necrotic abnormal,

16:18

when you see this retropharyngeal lymph node and that retropharyngeal lymph

16:22

node, that brings us to this reevaluation of the nasopharyngeal fullness.

16:27

This is nasopharyngeal cancer metastasis entrepreneur device.

16:31

And let's study the FDG, right?

16:33

This was the one of the earliest cancers that we could have ever captured in

16:37

terms of the mucosal space infiltration. And as you can see here,

16:40

this was nasopharyngeal mass left-sided lymph node and

16:45

left-sided nodal disease.

16:48

The right-sided lymphadenopathy retropharyngeal did not show that much FDG

16:52

uptake, but is T one disease equal to such a benign course

16:57

and FDG is uh, uh, helping us answer that question.

17:01

Patient got routine chemoradiation three months later,

17:05

no evidence of disease primarily locally nodal or distant.

17:10

We'll look at this. 12 months later,

17:12

patient presented with widespread bone metastases, andous disease.

17:17

Unfortunately,

17:18

FDG PET is helping us to accurately at baseline follow up.

17:23

And in those cases we are still trying to identify what should be the high risk

17:29

features to help us understand which patients should be followed not

17:33

after nine months, but more closely.

17:37

And cancer of unknown primary.

17:39

I think everybody can pick up that mass on the right side.

17:42

It's a noodle mass Level two A level two A would most likely be coming

17:47

from the or, right? We all agree.

17:49

But MRI did not show anything at oropharynx.

17:53

TAL evaluation was pristine until we got the FDG PET MRI.

17:58

As you can see,

17:59

there is a metabolically active this punctate lesion at the right

18:04

phase of tongue and patient went to dl.

18:08

The resection has shown micro primary. I called micro because it was,

18:13

uh, 0.3 centimeters.

18:15

So we have high sensitivity identifying where the primary could be.

18:19

And as you can see here,

18:21

cancer upon primary right now is further worked up.

18:25

Is the standard of care with FDG PET CT or MRI, um,

18:29

because metabolic evaluation, uh,

18:32

will give you the answer and probably will convert your patient from cancer of

18:36

unknown primary to cancer of known primary,

18:41

another case, right-sided magmas. Can anybody see the primary?

18:48

Obviously this is making our, um, the, the,

18:51

the metabolic evaluation is making our life easier, right?

18:55

Phase of tongue most likely, right? But as clear as it looks on this, uh,

19:00

FDG PET ct, this patient had preceding contrast enhanced neck ct.

19:06

Local evaluation with uh, direct, um,

19:11

endoscopy as well as the neck MRI and none of these

19:15

have confidently revealed the site of primary disease.

19:19

And as you can see here we are at the basal tongue.

19:22

Within the molecule there is this metabolically active tissue and

19:27

pathology proven to be the primary and look at how big the

19:32

lymphadenopathy,

19:33

the nodal masses are in the neck and look at how insignificance the primary

19:38

looks on MR if we don't have the FDG PET information.

19:43

So in that patient, let's take a look at the timeline of events.

19:47

Baseline presentation, base of time, primary right level two,

19:52

extend to level three, uh,

19:54

metastatic lymph apathy a year later,

19:57

completely free of disease. Five years later,

20:02

patient came back with local recurrence.

20:06

Patient's recurrence was right at the deeper aspect of the basal tongue,

20:11

but FDG PET did not really, um,

20:14

miss that despite the fact that patient was having mild basal tongue pain.

20:18

We were, we do see pain, uh,

20:21

or mucosal dryness in patients when they receive radiation radiotherapy.

20:25

And this patient's pain was very mild. It did not really, uh, ring, um,

20:30

any bells to image him earlier than he has expected. And plant, uh,

20:35

FDG PET CT as a part of his surveillance. As you can see here,

20:39

local recurrence, no notes noticed the metastasis this patient was,

20:44

um, successfully treated as well. Right? Neck lymph apathy, right,

20:49

we are going from the neck lymph nodes.

20:51

This patient presents with this extensive right level two three extending to

20:56

four lymph apathy. Initial workup because of the level four, uh,

21:00

involvement was whether we were dealing with, uh, some sort of thyroid lesion.

21:04

But as you can see, the MR shows, uh, MR did not show anything. The third,

21:09

we are at the glottic level, no mass. We are in the supraglottic novel.

21:13

Basal tongue right alytic fault are infiltrated by this mass,

21:18

which is already extending towards the extra laryngeal tissues.

21:22

It's already infiltrating the right thyroid car cartilage and moving outside

21:28

as we go higher, we see piece of it at the, uh,

21:32

right within the molecule as well. And as we go higher,

21:35

we're seeing this wig looking enhancement,

21:38

but how many times we see this asymmetry, um,

21:43

asymmetrical fat suppression and MAs looking MAs like uh,

21:48

or pseudo masses in this patient, it was exactly the same, uh, rule, right?

21:54

The larynx is normal. Supraglottic larynx harvest,

21:56

this mass extends to d uh, lytic fault as well as the um,

22:02

molecule with multiple lymph nodes.

22:04

And what was going on on the left was a total mystery until we did

22:09

the FDG PET ct. So let's study the case. Case again,

22:13

right lymph nap.

22:14

FDG positive metabolic knee active lymph nodes,

22:18

metabolic knee active primary already outside as you can beautifully see it here

22:23

already outside the larynx as we go higher, the right uh,

22:28

orotic fault is full of cancer.

22:30

So to say it's already outside the larynx and what's going on on the left,

22:34

we have a synchronous primary mass at the left tonsil.

22:39

So metabolic evaluation clearly identifies right side of lymph neuropathy

22:44

is related to the right, uh, supraglottic,

22:49

uh, primary mass.

22:51

But on the other hand there is the left sided primary that was totally unknown

22:55

and there is no lymph neuropathy on the left side. That's a very, uh,

23:00

unfortunate case because an elderly patient, uh,

23:03

comes with difficulty swallowing. And as you can see here,

23:06

the pictures speak for themselves, right?

23:09

We are looking at this posterior oropharyngeal wall,

23:12

extensive mucosal abnormality and on axial

23:17

image.

23:18

Now we can call this mucosal abnormality as a mucosal mass I guess because it's

23:23

this enhancing thickening, mucosal thickening in the prevertebral space,

23:28

uh, as well as the posterior pharyngeal wall. It stands from left to right,

23:34

left to right and look what it looks like. Yes,

23:38

the posterior phal mass, which is luckily the least common, uh,

23:41

presentation of FRAs cancer

23:46

is metabolically active.

23:48

But there was this lymph node that was questioned by the MRI,

23:51

whether it was a metastatic lymph node or just reactive lymph neuropathy

23:55

metabolically, it is absolutely cold and we can confidently say that yes,

24:00

we are dealing with locally extensive disease at the posterior pharyngeal wall,

24:04

oropharyngeal wall, I mean more accurately,

24:06

but this lymph node we can let it go.

24:08

So FDG PET is telling us IT and zero disease.

24:12

Switching gears talking about FDG pets, I have shown you, um,

24:17

seven cases of squam cell carcinoma, mostly in nasopharynx, aev,

24:22

uh, oropharynx,

24:23

and ultimately a very rare representation of posterior oropharyngeal valve.

24:28

As you can see here, um,

24:31

a seizure neuroblastoma is one of the true skull-based masses, right?

24:36

It is, uh,

24:37

it originates from the olfactory bulb can go south into the nasal cavity

24:42

at mid sinuses can go north into the brain.

24:45

This has decided to go to do both this in this patient. Uh, do we,

24:50

how often do we image those patients with, um, FDG PET ct?

24:55

Not that often,

24:56

but in that patient what has prompted the FDG PET CT evaluation was,

25:01

despite this primary presentation being stuffy nose,

25:04

patient was suffering from excruciating back pain that was not localizing to a

25:09

single level or to a bone or muscle, uh,

25:12

that could be identified by an oncologist.

25:15

So after discussing what we could do instead of going with multilevel,

25:20

excuse me, MRIs, uh, for cervical,

25:24

thoracic or lumbosacral spine,

25:26

we decided to go with FDG PET CT and obviously that was the

25:31

correct answers or we were just lucky.

25:33

I'm not sure because what we see here is this multiple sclerotic lesions

25:38

that are metabolically active by the initial presentation

25:43

of stuff nose patient was already dealing with and one metastatic

25:48

bone disease. But there was really not much of a way to have a general,

25:53

uh, look to in anesthesia glioblastoma cases, right? So a general look, unless,

25:57

uh, you scan the brain,

25:59

the spine at the same time and in that patient as much as the lesions are

26:04

sclerotic and metabolically active,

26:06

the earlier presentation in those cases could be completely normal.

26:11

Bone on CT with just, uh,

26:14

mild DG uptake that is not conforming to a physiologic

26:19

distribution and that could be the only clue in some of these cases.

26:23

So this was an ES stage neuroblastoma with bone metastasis.

26:27

And let's switch over radiopharmaceutical mouth after metabolic evaluation.

26:32

Let's switch to the somatostatin receptor type two based evaluation.

26:36

The commercial name is Dotatate pet. You can combine it with CT or mr,

26:41

but let's remind ourselves dotatate pets, uh, selectively

26:46

bins to do somatostatin receptor type two at the cell surface.

26:50

Somatostatin receptor type two is over expressed by all these

26:55

diseases.

26:57

Most commonly had an neck paragangliomas thyroid cancer,

27:03

the anesthesia neuroblastoma as well.

27:05

And P two adenomas in selective cases, uh, are going to be,

27:10

um, a part of your daily practice if you do do rotate PET ct.

27:15

Uh, the medulloblastoma, uh, is really very rare and it's pertinent to the kids,

27:19

but I just want to put it here just in case if you hear it. Uh,

27:23

on the other hand, mekel cell carcinoma, as much as dotatate is, uh,

27:28

highly selective for mekel cell evaluation,

27:32

I find in our practice it to be more common to do both.

27:36

So we do FDG PET in some patients it doesn't show up much and now we do do teeth

27:41

pets or vice versa. So I will show you more definite cases.

27:46

Let's start with this, uh, young lady.

27:49

She presents with left sided masks with tinnitus and we are looking at perfect,

27:54

uh,

27:55

it's a bookcase perfect imaging features or pathognomonic imaging features of

28:00

a left, uh, vagal paraganglioma.

28:04

The internal and external cry arteries are displaced from

28:09

the internal jugular vein. They're together. They're not split,

28:12

they're displaced. That's enough feature of vagal paraganglioma.

28:16

It's displaces the internal and uh,

28:20

external cord arteries together away from the internal jugular vein.

28:24

So what is that abnormal about this case, right?

28:27

And do we need any further imaging?

28:30

She was coming from a family of ADHP mutation carriers and prompted

28:35

that scan. Lucky for her,

28:39

it was the DO PET has shown us it was a single paraganglioma

28:45

on the left, a single vagal per gang, nothing in the bones,

28:49

in the liver or elsewhere in the body.

28:51

This was a patient followed for, uh,

28:55

familiar SDHB mutations for a long time and she had no

29:00

scans done before until, uh,

29:03

this presentation with tinnitus and palpable, uh, agma.

29:07

So right now we are doing more and more screening. Um, do pet, uh,

29:12

CT or MS in those patients. Just want to put it out, uh,

29:17

in familiar SDHX mutations.

29:22

If it shows increased, uh, number of lesions in the,

29:26

uh, family members, we tend to, uh,

29:31

scan those patients.

29:32

I mean screen those patients even if they don't have any symptoms or any

29:36

palpable lesions. And you can see this patient had ate PET

29:41

MRI as mnemonic as the ctma MRI shows this, uh,

29:46

salt and pepper morphology on pre contrast T one enhancement as well

29:51

as signal flow voice on T two showing intra, uh, lesional vascularity.

29:55

That's a different patient.

29:57

And she was followed for a right uh, dur,

30:02

got panic paraganglioma, uh,

30:04

at that age after being followed for a long time. Uh,

30:08

do we need to do and showing that mass has been stable,

30:12

but do we need to do any further, uh,

30:15

workup with doty pets or, um, anything else?

30:19

So that patient came to, um, er multiple times with um,

30:24

fainting episodes.

30:26

So we just want to make sure that the body was not harboring anything

30:31

outside this lesion.

30:33

Although the head and neck para ganglia must tend to be non secretory,

30:37

they don't secrete, uh,

30:39

the metanephrines and so forth in this patient

30:43

with stable, uh, disease on cross-sectional imaging with new symptoms.

30:48

It's our job to make sure that nothing else is going on, lucky enough, right?

30:53

Right. Skull base ULAR diagnostic, um, sorry, Jugl panic. Um,

30:58

paraganglioma, nothing in the nodes, nothing in the uh,

31:02

outside elsewhere in the body. What if D Sorry, what? Uh,

31:06

Durate pet history US is centers in the jugular fossa. Beautiful.

31:11

But look at this,

31:13

the little slip that goes into the uh,

31:17

TPA cavity TPA component on T two. It looks like a fusion.

31:22

T one says, oh yeah, there is enhancement,

31:23

it could be mass and from ct we know it's in continuity with the mass.

31:28

So Durate is showing us beautifully the true extent of the disease.

31:33

This patient was not that lucky I guess. Um,

31:38

long time ago she has had uh,

31:40

right carotid body per gang resection and she comes back with

31:45

swallowing difficulty just by the size of this mass.

31:48

You can imagine swallowing difficulty could be the case,

31:52

but still we need to exclude anything at the skull base that is compressing the

31:56

uh, vagal nerve or anything in the neck that may be compressing the recurrent

32:00

laryngeal nerve. So what did we do is Dotatate pet obviously.

32:05

And notate PET has unfortunately showed us metastases in the counter

32:10

sinus,

32:11

local recurrence in the correct body prior to resection was but

32:17

diffuse bone metastases.

32:19

All these foci that you see here are in the bones.

32:23

Luckily nothing in the liver or in the soft tissues or in the lungs,

32:27

but this was already M one disease.

32:31

Distant metastasis through the bones as well as multiple lymph nodes

32:36

as well as the counter sinus uh, lesion that I showed you.

32:39

so.pet is helping us to accurately uh,

32:44

stage this patient for providing the best pro prognostic

32:49

information as well as the best patient management options in those patients.

32:53

Right now what we do is when we see this multiplicity, uh,

32:57

they definitely get SDHB uh, both um, germline and uh,

33:02

tissue-based, uh, somatic analysis to be able to um,

33:07

give risk to be able to validate their risk factors for their offsprings.

33:11

And we do closely follow these patients with dote PET as well.

33:15

Another patient. This done with bilateral paragangliomas,

33:19

you can see those are carotid body para gangs be because unlike the other case,

33:24

the internal and external car arteries are split

33:29

and it's right at the bifurcation. So do we need the FDG?

33:33

So do we need do rotate PET in this patient? Um, very similar answer, right?

33:38

If they have family risk factors,

33:40

if they have multiple bilateral CRO body lesions, uh,

33:44

correct body paragons, uh,

33:47

we use the same analogy and we do scan or screen those patients

33:52

with doto teeth PET for distant metastases.

33:56

And how many paragangliomas do we see? Let's count.

34:00

Those are the known per ganglius.

34:03

And these are the unknown per ganglius that only

34:08

Durate PET is showing us. And this left

34:13

lower neck mass was not picked up on the clinical evaluation

34:18

as well as this mass was not picked up.

34:21

So what we are seeing here is this patient not only has bilateral crowd body

34:25

tumors per gangs,

34:26

but at the same time multiple per gangs distributed throughout the neck.

34:31

So this patient will definitely need closer follow up,

34:35

closer screening, uh, sorry, not screening. Let's be more accurate here.

34:39

Closer follow up for VE for surveillance and closer follow up.

34:44

Unfortunately because these lesions are not measurable,

34:48

the closer follow up means closer ative petr, uh,

34:53

or PET CT evaluations. Because these are at high risk,

34:58

these patients are at high risk for developing bone or liver or lung metastases

35:02

and the earlier we capture them the better um,

35:05

patient management tools we may provide. That's a summary.

35:09

I try to show these four uh,

35:12

patterns of dotatate in head and neck Paraag.

35:16

It can be a single mass on the left as you can see vagal parag,

35:20

it can be a single mass on the right, right at the skull base.

35:23

Look at this background is zero and recognition of any abnormal activity

35:28

is pretty easy.

35:30

This is a right-sided jugl panic per gang multiplicity,

35:36

multiple per gangs beyond multiplicity.

35:39

If use bone metastases and Durate PET successfully helps us

35:44

understand because per gang is um,

35:47

known to overexpress somatostatin receptor type two,

35:51

which is the target of that radiopharmaceutical.

35:55

And this is just a reminder on, uh,

35:58

CT how vagal and carotid body tumors would look differently in terms of

36:03

how they, uh,

36:04

displace the vessels carotid body despite being more um,

36:09

lower in the neck right at the purification is going to display the arteries.

36:14

But vagal paraganglioma it can be anywhere in the neck,

36:18

but if it's above the uh, cryo application,

36:21

it's going to split displace internal and external cry arteries away

36:26

from tron jugular vein. And what about this one?

36:30

This was a right um,

36:33

skull-based mass as you can see here.

36:36

And imaging properties were inseparable in terms of enhancement. T one,

36:41

T two um,

36:43

were inseparable from the paraganglioma versus oma,

36:48

although in the retrospect on T one,

36:51

this T two appearance is really not very um,

36:55

typical of a paraganglioma. In retrospect everything is there, right? Uh,

36:59

we were not able to confidently identify or differentiate paraganglioma from

37:04

Wanola and we ended up doing Dototate pet. And as you can see here,

37:07

there is no uptake where the lesion is.

37:11

So this was a case of schwannoma As much as positive Doty

37:16

PET is helpful,

37:18

negative Doty PET is also helpful as you can see here,

37:22

differentiating the schwannoma from a paraganglioma

37:27

and they, that takes us to this uh,

37:29

case from the literature because I don't have such a good one.

37:33

Medullary thyroid cancer, uh,

37:36

is known to over express, um,

37:40

cetin receptor type two as well. And these are uh,

37:44

side-by-side comparisons of Dotatate PET with

37:49

FDG PET as much as it expresses somato certain receptor type

37:54

two and can be easily picked up on dotatate PET is seen

37:59

here, right?

38:00

It can express it or it can be metabolically

38:05

active as you can see here and show some distant

38:10

metastases in soft tissues as well.

38:13

So this is a nice representation of how biphasic the

38:19

cancer could get when it becomes D differentiated.

38:23

The same thing applies to uh, prang gliomas.

38:27

The more D differentiated they get,

38:30

the less ate avid they will be the more FDG AVID they will

38:35

get.

38:35

So this is to show that in major heart cancer or in

38:40

any D differentiated per or even in stage neuroblastoma as well,

38:45

Dotatate and FDG PET are not competing but complimenting each other.

38:50

Bone lesion is dototate positive because this metastasis

38:55

overexpresses somatostatin receptor type two as opposed to being

39:00

metabolically cold and other soft tissue lesions could be FDG

39:05

positive as opposed to being asst two positive.

39:10

Um, in summary,

39:13

PET is essential for accurate baseline staging,

39:17

which is the element that we use for AJCC eight, uh,

39:22

evaluation, right? And that staging,

39:25

accurate staging will put the patient in the best location to start the,

39:30

um, best management possible for the NCCN guidelines.

39:34

And for the follow up, we're still exploring the follow up for um,

39:40

uh, disease like Angliss, Blass, stomas,

39:43

a stage neuroblastomas because it's really not feasible or practical to do

39:47

FDG or Durate PET in every patient just because we think something is wrong

39:52

and that's why the guidelines are for. So I would kindly suggest you to, um,

39:57

become a member of the an CCN website and once in a while take a

40:02

look at the guidelines. Whenever there's an update you get an email, uh,

40:05

anyway and whenever you read your scans, um,

40:09

it's a good idea to read the scans per the established staging manual of

40:13

AJCC to eight. Uh, I find it very useful, uh,

40:18

in cases we need to know which tracers to use so that we can make the best uh,

40:22

use out of them. Like as much as for headon neck,

40:27

squamous cell carcinoma FDG is indicated when a patient presents with

40:31

dedifferentiated paraganglioma, it's not going to be dod,

40:35

it's going to be FDG as well for systemic evaluation for head and

40:40

neck, I try to show a few, um,

40:42

PET MR versus PET CT cases as, uh,

40:48

you could see in those slides the pet MR because of its highest

40:53

uh,

40:53

higher resolution performs way better than the PET CT most of the time for head

40:57

and neck oncology, unless we wanna see what's going on in the bones,

41:01

obviously for bone erosion,

41:04

but definitely for intracranial scalies and filtration for camera signs.

41:07

Medical scale for perone spread PET MR is, uh,

41:12

incomparably better than the PET CT for the lymph nodes.

41:16

The lymph nodes may look really, um,

41:18

abnormal on CT or MRI but if you are not sure

41:23

either suggest to get an FDG PET as I try to show you,

41:28

no matter how insignificant the lymph nodes were,

41:30

they still could be metastatic.

41:33

If you don't have that option,

41:34

at least suggest to get an FNA so that the FNA can tell you, uh,

41:39

the accurate noal state so that the patient can be treated accordingly

41:44

for any primary of unknown origin,

41:46

this is pertinent to every lymph node that is shown to be, um,

41:51

cancerous without a identifiable primary through the C two

41:55

M-R-I-F-D-G PET CT should be the first step.