Sentinel Lymph Node (SLN) sampling is being performed for low stage squamous cell carcinomas (SCC) of the Head & Neck, usually small oral mucosal SCCs with clinically and radiographically negative necks.
- A POSITIVE sentinel node will prompt full neck dissection.
- A NEGATIVE sentinel node will spare the patient a neck dissection and allow for preserved lymphatic drainage (minimizing morbidity).
Some cases may come for permanent evaluation only; Some may come for frozen. In either case please follow this protocol for grossing and submission of cassettes:
- Measure tissue (image 1 below).
- If excess fate is present around the node, trim the fat away from the node (Image 2 below).
- Sectioning will depend on the size of the node (Image 3 below):
- If node is < 2 mm in greatest dimension, process the node intact (DO NOT SECTION GROSSLY).
- If the node is between 2 and 5 mm in greatest dimension, BISECT the node parallel to the long axis.
- If the node is > 5 mm in greatest dimension, SERIALLY SECTION the node in 2 mm increments parallel to the long axis.
- If the specimen is for:
- Frozen: Freeze all sections from sentinel nodes (NOT including fat), placing each section on a separate chuck/block. Cut the standard 2 H&E Cryo sections at 4 microns.
- Permanent: Submit all sections from sentinel nodes. If node is large, place each section in a separate cassette. If small, 2-3 sections can be placed per cassette
- For either case, submit any trimmed fat in a separate cassette.
- Regarding final processing:
- If the Frozen Section is POSITIVE for SCC, then only 1 routine H&E is needed for all blocks.
- If the Frozen Section is NEGATIVE for SCC or the node is only sent for PERMANENT evaluation, then please ensure that the “Sentinel Lymph Node for H&N SCC” Part Type and Protocol is activated for each cassette with lymph node (not for the fatty cassette(s)). Please ask gross room staff or attending if you are unsure (see below for protocol).
- These cases should also come with a Primary Mucosal Resection (which also may or may not be sent for frozen).
- Please ensure that these cases are submitted same-day (or early next day if needs fixing) with RUSH / PRIORITY indication. The patient and surgeon are waiting for the results of the sentinel nodes to determine the need for additional neck dissection.
H&N Sentinel SCC Protocol
Specifically, the protocol ensures both multiple H&E Levels, with intervening Unstained Levels and Keratin Stains:
- Intra-op consult – CRYO
- Intra-op consult additional – CRYO
- FS permanent slide L1 H&E
- *Unstained L2
- AE1/AE3 – Note: Use Unstained Level 2
- *Unstained L3
- *Unstained L4
- *Unstained L5 – Note: Cut 150um dpr to get to next level
- FS permanent slide L6 H&E
- *Unstained L7
- AE1/AE3 – Note: Use Unstained Level 7
- *Unstained L8
- *Unstained L9
- *Unstained L10 – Note: Cut 150um dpr to get to next level
- FS permanent slide L11 H&E
- *Unstained L12
- AE1/AE3 – Note: Use Unstained Level 12
- *Unstained L13
- *Unstained L14
- *Unstained L15
New 2021-04 NAC