Soft tissue
Uncertain differentiation
Clear cell sarcoma
Author: Vijay Shankar, M.D.
Topic Completed: 1 November 2012
Minor changes: 5 April 2021
Copyright: 2002-2021, PathologyOutlines.com, Inc.
PubMed Search: Clear cell sarcoma [title] soft tissue
Table of Contents
Definition / general | Case reports | Treatment | Clinical images | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Cytology images | Positive stains | Negative stains | Electron microscopy description | Molecular / cytogenetics description | Molecular / cytogenetics images | Differential diagnosisCite this page: Shankar V. Clear cell sarcoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/softtissueclearcellsarcoma.html. Accessed April 19th, 2021.
Definition / general
- Also known as melanoma of soft parts
- Rare aggressive tumor of adolescents / young adults
- Median age 30 years, range 13 - 73 years; 60% male
- Deep soft tissues of extremities, trunk or limb girdles, tends to occur near tendon, fascia or aponeuroses
- Slow progression, frequent local recurrences; eventually nodal and distant metastases
- 5 year overall survival is 63% (Am J Surg Pathol 2008;32:452)
- Size is most significant prognostic factor (Dermatol Res Pract 2012;2012:984096)
Case reports
- 35 year old woman with tumor of foot (Case Rep Oncol 2012;5:449)
- 40 year old man with cutaneous tumor of lower leg (J Lab Physicians 2012;4:53)
- 53 year old Caucasian man with painful lesion on arm (Indian J Dermatol 2009;54:168)
Treatment
- Complete surgical resection
Clinical images
Images hosted on other servers:
Arm
Gross description
- Firm, well circumscribed, gray - white, gritty sensation when cutting
- Median 4 cm, range 1 - 15 cm
- Variable necrosis
Gross images
Contributed by Mark R. Wick, M.D.
Tendon
Microscopic (histologic) description
- Distinctly nested growth pattern with mixture of spindle, epithelioid and tumor giant cells
- Melanin pigment in 2 / 3
- May have floret-like multinucleated giant cells
- Often rhabdoid cells, bizarre pleomorphic cells
- Usually necrosis
- Mean 4 MF / 10 HPF
Microscopic (histologic) images
Contributed by Mark R. Wick, M.D.
Tendon
S100, HMB45, Fontana Masson
Images hosted on other servers:
Arm
Lower leg tumor
Foot tumor
Cytology description
- Variable cellularity; may form microacinar structures resembling adenocarcinoma (Am J Clin Pathol 2002;117:217)
Cytology images
Contributed by Mark R. Wick, M.D.
Tendon FNA
Positive stains
- S100, HMB45, microphthalmic transcription factor (75%, Mod Pathol 2001;14:6), melanoma cell adhesion molecule, MelanA (43%), iron (intra- and extracellular), Leu7 / CD57, vimentin, keratin (variable)
Negative stains
Electron microscopy description
- Melanosomes
Molecular / cytogenetics description
- t(12;22)(q13;q12): ATF1 and EWS (not seen in melanoma)
- Usually diploid or less aneuploidy than metastatic melanoma to soft tissue
- Tumors in GI tract may have a variant fusion gene EWSR1 - CREB1
Molecular / cytogenetics images
Images hosted on other servers:
FISH
Differential diagnosis
