Mucosal excisions are occasionally being sent for intraoperative evaluation (frozen section) to determine either:
- Depth of invasion of SCC (3 mm or more is an important cutoff)
- Distance of SCC to nearest deep and/or peripheral margin(s) (1 mm or less is an important cutoff)
These specimens should be oriented, inked, and sectioned FRESH in the same manner that you would normally proceed for an oriented mucosal excision:
- Measure the specimen in 3 dimensions, as usual (refer to complete mucosal excision for additional details).
- Ink the deep and peripheral margins in 2 colors, parallel to the long axis of the specimen:
- In order to facilitate fresh sectioning, you may gently submerge the specimen in liquid nitrogen. This process firms the tissue, and allows the mucosa, muscle, and fat to be serially sectioned into thin and regular slices: (This step is not required, but can be used if desired)
- Serially section the specimen perpendicular to the long axis. You can keep the two end or “tip” sections slightly thicker to facilitate perpendicular sectioning.
- Perpendicularly section the tips, if tumor is anticipated to be present in the tip sections.
- Evaluate for the closest point of invasion to deep AND peripheral margin(s), and freeze the relevant section(s). A good estimate of when to freeze is if the tumor is grossly 5-10 mm or less from margin.
- If no tumor is grossly present or if distant from margins, offer a gross-only report back to the surgeon.
- Microscopically, the DEPTH OF INVASION is measured from the nearest basement membrane to the deepest point of invasion, as a line perpendicular to the mucosa. Depth of approximately 3 mm or greater may prompt neck dissection.
- Microscopically, the DISTANCE TO MARGIN is measured as the distance from the tumor to nearest deep or perpendicular margin. Distance of 1 mm or less may prompt re-excision.
- AFTER THE FROZEN: Ideally, since the specimen has already been serially sectioned, it should be grossed immediately by the frozen resident/PA. The end margins should be further sectioned and submitted perpendicularly, if not already done. The central sections should be submitted sequentially, with slice numbers if possible:
SAMPLE GROSS DESCRIPTION:
A. Container label: Name, medical record number, & “Left tongue”
Received: Fresh for intraoperative diagnosis
Specimen: Partial glossectomy
Orientation: Long = Anterior, Short = Medial
Dimensions: 3.3 cm anterior-posterior, 3.0 cm right-left (medial-lateral), 2.0 cm superior-inferior (superficial to deep)
Ink: Lateral half inked black, Medial half inked blue
Mucosal lesion: 1.5 x 1.0 x 0.4 cm, red-ulcer, located 0.6 cm from lateral, 0.7 cm from medial, 0.6 cm from deep, 0.9 cm from posterior and 1.9 cm from anterior.
Serial sections: 8 sections, from anterior to posterior, slices 3-7 with ulcer
Gross photographs: Yes
Cassette Summary: Entirely submitted:
A1-FS: Slice 4, approach to deep margin
A2: Anterior tip, perpendicularly sectioned (Slice 1)
A3-4: Posterior tip, perpendicularly sectioned (Slice 8)
A5: Slice 2
A6: Slice 3
A7: Slice 5
A8: Slice 6
A9: Slice 7
Gross images courtesy Kyle Parker, MD