Commonly seen on the head/neck area of
elderly patients. Tumor often consists of infiltrative spindle cells
that mimic spindle cell melanoma, atypical fibroxanthoma or
leomyosarcoma. A very important hint is that the spindle cells may
continue with the dysplastic epidermis.
IPX: CK5/6+, but may be
Spindle cell melanoma
has to be ruled out. Tumor cells may show deep dermal infiltration
with formation of vague fibrotic nodules and lymphocytic aggregation.
Perineural invasion in common. S100+, other malanoma markers not very
broad, pink cytoplasm, blunt nuclei with perinuclear clearing, SMA+
CD68+, S100-, CK-