Cytologic detection of penile malignant melanoma of soft parts in pleural effusion using monoclonal antibody HMB-45.

Abstract

A case of penile malignant melanoma of soft parts ("clear cell sarcoma") with pulmonary metastases and malignant effusions is reported. The tumor cells in the pleural effusion were scattered singly and admixed with reactive mesothelial cells. They had abundant granular cytoplasm and round nuclei with prominent nucleoli. Although staining for S-100 protein was positive in sections from the penile lesion, it was negative in sections of a cell block prepared from the effusion; however, the effusion tumor cells demonstrated immunoreactivity with HMB-45, an antimelanoma monoclonal antibody.