Sertoli-Leydig cell tumor of the ovary masquerading as a mucinous adenocarcinoma: a frozen section pitfall.

Sertoli-Leydig cells tumors are rare ovarian neoplasms that can be managed with conservative resection given their generally excellent prognosis. Here we report a case of Sertoli-Leydig cell tumor mistakenly diagnosed as an invasive mucinous adenocarcinoma at time of intraoperative consultation because of its blue-mucinous appearance in the frozen section material. The patient subsequently underwent an extensive staging procedure revealing unilateral, ovarian confined disease. The mucinous features seen on frozen section were lost on the slides prepared from formalin fixed tissues. Immunohistochemical work up confirmed the diagnosis of a pure Sertoli-Leydig cell tumor. No heterologous elements were identified in this tumor. This case illustrates a hitherto unrecognized frozen section pitfall in evaluation of ovarian neoplasms. To the best of our knowledge, this is the first well documented case of pure Sertoli-Leydig cells tumor which resembled a well differentiated mucinous adenocarcinoma during frozen section.