A Case of Malignant Melanoma of Soft Parts with Unusual Histopathologic Findings

ABSTRACT

We report a case of malignant melanoma of soft parts presented with a hard mass on the dorsum of the left second toe. Malignant melanoma of soft parts has also been known as clear cell sarcoma of tendons and aponeuroses, which indicates the histologic feature of clear cell predominance and the origin of tumor cells, tendinous or aponeurotic structures. Although our case presented with many characteristic clinicopathologic features of malignant melanoma of soft parts, diagnosing this case as malignant melanoma of soft parts was made with great difficulty because of a rather unusual finding that the major cell component of neoplasm was spindle shaped cells in stead of clear cells. Cases featuring this distinctive histopathologic finding have not been reported individually to our knowledge, but described briefly in the literature. We think this case deserves special attention because of its close resemblance to various sarcomas.