Case 208 - Discussion
Uploaded: 2008-05-03, Updated:
Positive: S100, vimentin, melan
Negative: CD45, CD15, CD30,
<5% melanomas are amelanotic;
The metastases of pigmented primary
melanomas may be amelanotic clinically and histologically;
In 3-5% of metastatic melanomas,
the primary tumors are not identified;
S100: most sensitive but lest
Desmoplastic and spindle cell
melanomas are most commonly negative for Melan-A and HMB45, but
almost always positive for S100.
No melanocytic marker can
distinguish benign from malignant melanocytic lesions.
Reference: PIP, 2008-A