Sentinel and regional lymph nodes -melanoma

• No
  • Non-routine fixation (not formalin), describe.

• Yes
  • Special studies required, describe.
  • Ensure samples are taken prior to fixation.²

• Not performed
• Performed, describe type and result
  • Sentinel node biopsy
  • Frozen section
  • Imprints
  • Other, describe

Record additional orientation or designation provided by operating clinician:

• Absent
• Present
  • Method of designation (e.g. suture, incision)
  • Featured denoted

• Sentinel lymph node
• Regional lymphadenectomy/lymph node dissection (see separate protocol for neck dissection)
• Other, describe

• Groin
• Axilla
• Other, describe

• Specimen size in three dimensions (mm)¹
• Radioactive count if known⁴
• Uptake of dye⁴
  • No
  • Yes
• Number of lymph nodes
• Size of each lymph node in three dimensions (mm)⁴

Protocols for the safe handling of radioactive tissue should be established in laboratories receiving sentinel lymph node biopsies. Consideration of the number of samples to which staff are exposed, the length of time specimens are left for radioactivity to degrade before macroscopic cut-up commences and the correct disposal of waste material.^5,6

• Orientation marker
  • No
  • Yes, describe
• Specimen size in three dimensions (mm)¹
• Number of lymph nodes^3,4
• Range of maximum diameters (mm)
• Largest macroscopically involved lymph node and/or matted tumour mass, if present
  • Maximum dimension of tumour (mm)
• Macroscopic extranodal tumour
  • Absent
  • Present, describe
  • Distance from surgical soft tissue margin (mm)
  • Distance from apex/apical node (mm)
  • Infiltration of vessels, nerves, skeletal muscle or other adjacent structures

• Absent
• Present see separate skin protocol for more detail

Each individual sentinel lymph node must be examined. Each lymph node should be carefully taken from the specimen with some perinodal fat so that the afferent lymphatics and perinodal tissue can be assessed for the presence of tumour.

Lymph nodes should be sliced at 2mm intervals through the convex capsule and the hilum and along the longest meridian.²

Submit all sections of sentinel lymph nodes for processing. Step sections through the block and immunohistochemistry are often used for the evaluation of sentinel nodes.

In current practice there is wide variation in how lymph nodes from regional lymphadenectomies are dissected and processed and the methods described below should only be considered as a guide.

Specimens should be examined carefully to maximise lymph node yield. Each lymph node must be blocked, examined and recorded in such a way so as to enable accurate measurement of lymph node numbers and involvement at microscopic examination. This is usually achieved by manual dissection of fixed tissue with careful examination by inspection and palpation.

Small lymph nodes, <5mm in maximum dimension, usually will not require dissection and can be submitted whole.

Lymph nodes > 5mm, serially section at 2mm intervals looking for grossly identifiable deposits.⁷

Please note that some institutions serially section all lymph nodes at 2mm whether for sentinel node analysis or for routine regional lymph node evaluation with the entire lymph node submitted for histological evaluation.⁸

Macroscopically involved lymph nodes may be bisected along the median plane to demonstrate the relationship of tumour to the capsule. One section of a macroscopically involved node is sufficient.

Where extracapsular extension is apparent or suspected, lines of dissection should extend through adjacent tissues to allow microscopic evaluation of extracapsular invasion.

The lymph node or tumour closest to the surgical margin should be so identified and sampled.^9,10 If extranodal tumour is close to the surgical soft tissue margin, the margin may be painted with ink. If oriented specify the margin.

If skin is present, identify and sample the previous biopsy track if possible. Any abnormal area should be sampled according to the skin protocol. In the absence of any abnormality one representative block is adequate.

If skin is present, identify and sample the previous biopsy track if possible. Any abnormal area should be sampled according to the skin protocol. In the absence of any abnormality one representative block is adequate.

Every lymph node identified should be examined histologically. The presence of matted lymph nodes or extension of tumour to specimen edges is rare but should be reported if apparent to assist with radiation therapy planning.^9,10

• Serially section all sentinel lymph nodes at 2mm intervals and submit all sections of each node in as few cassettes as possible.

• Macroscopically uninvolved lymph nodes > 5 mm n max. dimension should be serially sectioned and submitted in their entirety, preferably one node in each cassette.
• Lymph nodes <5mm in max. dimension can be submitted whole and more than one can be included in each cassette

• Bisect perpendicularly to first dissection line and submit one representative section demonstrating relationship of tumour to capsule and the closest surgical margin if applicable. One section of each node is sufficient.