Sarcoma
| Revised by Dr. David Lucas, 12/2012 | ||
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SOFT TISSUE TUMORS
Benign Soft Tissue TumorsSimple Excision
Sections for histology
Soft Tissue TumorsSoft tissue sarcoma
Introduction: - Soft tissue sarcomas are complex specimens that often include skin, bone or visceral organs. Careful attention to surgical margins is critical. The tumors are highly variable in shape, pattern of invasion (infiltrative vs encapsulated), color and consistency. Consistency varies from fleshy to fibrous to gelatinous to fatty. Areas of necrosis and intralesional hemorrhage are common and highly variable among tumors.
Extremity tumors are ideally treated by either wide local excision or amputation. However, positive or close margins may be acceptable for tumors close to bone, neurovascular bundles or other important anatomic structures. Unlike extremity sarcomas, it is diffuclt for surgeons to achieve wide margins in retroperitoneal tumors due to anatomic constraints. Therefore, such tumors are marginally excised at best and often have positive margins. They are often resected along with visceral organs (kidney, adrenal, spleen, bowel, etc.)
High-grade sarcomas are frequently treated with preoperative therapy which alters the appearance of the tumor, causing necrosis and fibrosis.
1. Extremity sarcomas treated by wide local excision:Procedure:
-Weigh and measure the specimen in 3 dimensions.
-Note the orientation. Usually one can divide the margins into medial, lateral, superior, inferior, superficial and deep. Tumors from Dr. Biermann are marked by a suture at the 12 o'clock position, such that the margins can be oriented by clock face designations as well as by superficial and deep planes (See below).
-Note the presence or absence of a skin ellipse on the specimen. Deep-seated tumors usually have a small ellipse with a scar or no skin at all, while superficial tumors usually have a much larger skin ellipse. Measure it in 2 dimensions. Measure the scar if present.
-Examine the outer surface of the specimen. Note what tissues surround it (e.g. skeletal muscle, fascia, adipose tissue, etc.) and where these tissues are located. Surgeons will often mark areas of interest such as close margins (near bone or neurovascular bundles) by sutures.
-Look for any areas of exposed tumor and note the location and area size. Carefully palpate the surface and access whether or not the surrounding tissues are freely moveable (this is best done in the fresh state). Pay attention to areas where tissue is adhered to the tumor as these may represent close or positive margins.
-Apply ink to the margins (for Dr. Biermann's cases the following colors of ink should be used: deep-black, superficial-yellow, 12-9 o'clock-blue, 9-6 o'clock-orange, 6-3 o'clock green and 3-12 o'clock red).
-Turn the specimen such that the skin surface is down.
-Using a long-bladed knife, carefully breadloaf the specimens at 1 cm slices perpendicular to the long axis of the tumor carefully noting the relations and measurements to the margins. Note the level of encapuslation vs invasive growth and satellite nodules. Note the variation in thickness of the margins in cm and where the close margins are located. Note whether the tumor involves the dermis, subcutis, fascia and/or skeletal muscle. Carefully describe the cut surface in terms of color and consistency. Estimate the approximate percent necrosis. Note the presence of any entrapped structures such as tendons, nerves and large caliber blood vessels.
For specimens with attached bone, note the relation of the tumor to bone (how far away). If it is adherent or directly invades bone, take a section for decalcification.
Sections for histology:
-Sample the margins generously; especially close margins, with perpendicular (not shave) sections.
-Sample tumor not at margins paying attention to anything that looks different.
-Sample any important anatomic relations including entrapped structures.
2. Extremity sarcomas treated by amputationProcedure:
-Describe and measure the specimen. Note any ulcerations, satellilte nodules, scars or areas of edema or induration. Note the exact site of the amputation (or disarticulation). Note the extent of bone beyond the soft tissue margin if applicable.
-Ink the margin.
-Incise the skin and underlying tumor (usually a longitudinal section provides the best exposure). Carry the incision down to the bone.
-Make additional parallel sections taken to evaluation extent of tumor, presence of satellite nodules and the relation of the tumor to underlying anatomic structures.
-Measure the tumor in 3 dimensions. Describe the consistency, color and shape of the tumors. Note whether it involves dermis, subcutis, fascia, muscle or bone.
-For tumors that adhere to or invade bone, submit a section for decalcification. Note any entrapped anatomic structures such as tendons, nerves or large caliber blood vessels.
-Estimate the percent of tumor necrosis.
-Measure the distance to the margin of amputation.
Sections for histology:
-Sample the tumor paying attention to anything that looks different.
-Sample any important anatomic relations including entrapped structures.
-Sample the margin (more than section may be required to close margins).
-Decalcified sections if indicated.
3. Retroperitoneal resections
Procedure:
-Weigh and measure the specimen in 3 dimensions
-Identify and measure any visceral organs and their relation to the tumor.
-Palpate outer surface of the tumor. Note if it has an intact pseudocapsule, determine if the outer layer of tissue is freely moveable over the tumor.
-Search for any exposed tumor or adhesed areas and measure the size area.
-Ink can be placed in strategic areas prior to cutting.
-Using a long-bladed knife, breadloaf the tumor paying close attention to margins. Measure distance to close margins.
-Describe consistency and color of the cut surface.
-Note if tumor is well demarcated or infiltrative.
-Dissect any visceral organs in the standard fashions, and note the relation to the tumor (specifically if the tumor separated from the organ, adherent to it, or invasive into it).
-Estimate percent necrosis.
Sections for histology:
-Sample the margins generously; especially close margins, with perpendicular sections.
-Sample the tumor paying attention to anything that looks different.
-Sample any important anatomic relations including entrapped structures.
-Sample the interphase of tumor to any visceral organ.
4. Ancillary studiesWhen feasible procure tumor for tissue banking.
Tissue can be sent for cytogenetics or electron microscopy.
SOFT TISSUE - SARCOMA
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KJT |
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