Case of mediastinal seminoma with testicular microlithiasis

Testicular microlithiasis is a rare condition in which calcified concretions fill the lumina of the seminiferous tubules. We report the case of a 19-year-old Japanese man with mediastinal seminoma, normal testicular physical findings and bilateral testicular microlithiasis seen on ultrasonography. Testicular needle biopsy demonstrated multiple laminated calcifications within the seminiferous tubules without any signals of a viable germ cell tumor. To our knowledge, this is only the sixth reported case of extragonadal germ cell tumor with testicular microlithiasis.