Malignant papillary mesothelioma of tunica vaginalis testis.

A malignant papillary mesothelioma of the tunica vaginalis testis with retroperitoneal lymph node and pulmonary metastases is reported in a seventy-seven-year-old man. Electron microscopy of a local recurrence documented its mesothelial origin. The clinical and pathologic features of these rare neoplasms are discussed.