Ovarian Sertoli-Leydig cell tumor with elevated serum alpha-fetoprotein.

An 18-year-old girl with virilization and an elevated level of serum alpha-fetoprotein (AFP) was found to have a Sertoli-Leydig cell tumor (SLCT) of the ovary. The tumor had a heterologous element of gastrointestinal type epithelium, retiform pattern, and multilocular cysts, many of which were lined by Sertoli-like cells. Alpha-fetoprotein was detected immunohistochemically in cells with the histologic appearance of Sertoli cells, and testosterone was detected in the Leydig cells. Results of lectin affinity chromatography indicated that AFP produced by this tumor was different from the AFP to be found in the liver.