Malignant mesothelioma of the tunica vaginalis testis: unusual sonographic appearance.

Malignant mesothelioma of the tunica vaginalis testis is a rare and aggressive neoplasm. It is similar to malignant mesothelioma of the peritoneum, usually associated with asbestos exposure. We present an unusual case in which the tumor was a mix of a hypoechoic solid nodule and a cystic component with low-level internal echoes.