Oropharyngeal Carcinoma: Nodal Drainage and Differential Dx
HIDEInteractive Transcript
0:01
Hello everyone.
0:02
Dr. Sidney Levy here, continuing our discussion of diagnosis
0:05
and staging of base of tongue squamous cell malignancy.
0:10
I would like to go through the patterns of drainage
0:14
of lymph nodes of base of tongue malignancy.
0:17
We have an example case that we are using.
0:20
This is a base of tongue squamous cell carcinoma,
0:24
which is involving both the right and left sides and
0:30
we can see that there is one abnormal lymph node here.
0:34
I will, uh, point it out to you.
0:37
So this lymph node here is situated within level 2A.
0:42
And we know that because it is posterior to the posterior
0:46
margin of the submandibular gland, which is here.
0:52
We also know that this lymph node is less than
0:55
3 centimeters, which we can measure easily.
1:01
So given that information and the fact that there aren't any
1:04
other lymph nodes on the right side or the left side of the
1:08
neck, we can say that this lymph node is a level 2A lymph
1:16
node, and the only one which is morphologically abnormal.
1:21
Base of tongue malignancy can drain to levels 2, 3, or
1:26
4, and often is bilateral, the reason being that many
1:31
tumors do cross the midline and involve the other side.
1:35
Oropharyngeal malignancy, including base of tongue
1:40
malignancy, can often be human papillomavirus
1:44
positive, particularly in more recent years.
1:49
These lymph nodes tend to have a more cystic morphology
1:55
and can be easily mistaken for benign pathology
2:00
such as second branchial cleft cysts.
2:03
So this is a major pitfall when assessing lymph nodes in the neck.
2:08
Don't mistake
2:10
a morphologically abnormal cystic or necrotic lymph
2:14
node in the neck for a second branchial cleft cyst.
2:19
Often, cystic lymph nodes are more irregular, they have
2:23
a thicker peripheral margin, and, in particular, you must
2:30
look very carefully at the upper aerodigestive tract to
2:33
see if there is a lesion, which might be quite small.
2:37
If there is any doubt whatsoever, people
2:40
often sample these lymph nodes to make sure.
2:43
The last thing I'd like to go through are the
2:45
differentials for base of tongue squamous cell malignancy.
2:49
The differentials for base of tongue squamous cell
2:53
malignancy include minor salivary gland malignancy,
2:58
lingual tonsillar hyperplasia, lymphoma, other
3:05
oropharyngeal malignancy, so palatine tonsil malignancy,
3:09
which has spread to the base of tongue,
3:12
and benign mixed tumors such as pleomorphic adenomas.
3:17
So in summary, base of tongue oropharyngeal malignancy
3:22
often drains to levels 2 to 4 within the neck,
3:26
may often be bilateral. A significant proportion of
3:32
these malignancies are human papillomavirus positive
3:36
and therefore the nodes may be of cystic morphology.
3:39
And it is extremely important not to dismiss
3:43
a cystic lesion within the neck in this
3:46
region as a second branchial cleft cyst.
Sidney Levy, PhD, MBBS
Radiologist and Nuclear Medicine Specialist
I-MED
© 2024 Medality. All Rights Reserved.