Abstract
A 40-year-old woman visited our hospital because of a dome-shaped light red eroded-surfaced tumor measured 1.5×1.9×1.0cm on her right heel. On closer examination, a small dark brown pigmented macule was observed in its peripherary. Excision of the tumor disclosed the tumor to be amelanotic melanoma. The tumor was composed of anaplastic epithelioid cell nests with junctional activity. No melanin granules were appreciated. The tumor cells were positive for S100 and HMB45. Two weeks later wide local excision, sentinel node biopsy and ilio-inguinal lymph node dissection were performed. Although her right inguinal nodes were clinically palpable, no evidence for lymph node metastasis was obtained. The patient was diagnosed as amelanotic melanoma stage IIIA (pT4aN0M0 tumor thickness 4.4mm) and is currently followed without evidance for metastasis. This is the 3rd amelanotic melanoma patient among 91 cases malignant melanoma (3.3%) in our department. [Skin Cancer (Japan) 2000; 15: 185-188]
