The patient is a 15-year-old young man with normal sexual development and a history of a left testicular mass. The mass, evaluated by ultrasound, presents as a partially cystic nodule near the epididymis and measures 8 mm.GROSS DESCRIPTION:
The testicular biopsy received consists of an unoriented flattened portion of tan-white rubbery soft tissue measuring 1.5 X 1.0 X 0.5 cm.MICROSCOPIC DESCRIPTION:
H & E sections demonstrate a proliferation of cytologically monotonous and relatively bland Sertoli-like cells filling and distending tubules of the rete testis and adjacent seminiferous tubules. Focal microcalcifications are noted. Adjacent seminiferous tubules away from this proliferation consist of Sertoli only tubules, without obvious germ cells. There are a few aggregates of Leydig cells in the interstitium between some of the Sertoli only tubules, but in the areas of dense intratubular Sertoli cell proliferation there are only a few interstitial cells. No seminiferous tubules with normal spermatogenesis are identified within the biopsy.
Immunochemical evaluation shows that the monotonous cells and surounding normal rete testis epithelium are positive for low molecular weight cytokeratin (CAM 5.2). Adjacent seminiferous tubules containing Sertoli cells are negative for CAM 5.2.