๐Ÿ—‚ ็ธฝ็›ฎ้Œ„ ๏ฝœ ๐Ÿ“– ่‹ฑๆ–‡ๅŽŸๆ–‡๏ผˆๆœฌ็ฏ‡๏ผ‰ ๏ฝœ ๐Ÿ“ ๅฎŒๆ•ด็ฟป่ญฏ ๏ฝœ โญ ็ฒพ่ฏ็ญ†่จ˜

Prognostic indicators โ€” Differential diagnosis

Differential diagnosis

Amelanotic spindled cell melanoma may be histologically indistinguishable from other cutaneous spindled cell tumors including leiomyosarcoma, spindled cell squamous carcinoma, atypical fibroxanthoma, and even dermatofibrosarcoma protuberans. In such cases, the use of an appropriate panel of immunohistochemical reagents, including antibodies to S100 protein, SOX10, HMB-45 or MART-1, pan-cytokeratin, AE1/AE3, smooth muscle

1328 Melanoma

actin (SMA), and CD34, is often essential. Similarly, highly pleomorphic, amelanotic epithelioid melanoma sometimes has to be distinguished from anaplastic carcinoma and occasionally anaplastic lymphoma. The use of antibodies to keratins, epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA), leukocyte common antigen (LCA), T- and B-cell antigens, and CD30 may be necessary to achieve a definitive diagnosis.