Fine needle aspiration diagnosis of metastatic Leydig cell tumor. Report of a case and review of the literature

Abstract

Leydig cell tumors are rare sex cord-stromal tumors that account for less than 1% of all testicular tumors. Less than 10% of these tumors show metastatic malignant behavior. Herein we present a case of metastatic malignant Leydig cell tumor in an iliac lymph node diagnosed on fine-needle aspiration (FNA) in a 70-year-old man. The patient was referred from an outside institution with lymphadenopathy and had a past medical history of lymphoplasmacytic lymphoma/Waldenström's macroglobulinemia and past surgical history of orchiectomy. An iliac lymph node FNA was performed demonstrating large discohesive plasmacytoid cells with indistinct cell borders; abundant and finely granular cytoplasm; round, eccentric nuclei with evenly distributed chromatin; and prominent nucleoli. The tumor cells were positive for inhibin and negative for calretinin and keratin leading to the diagnosis of metastatic malignant Leydig cell tumor. Review of the patient's history and of previous pathologic material, careful evaluation of cytomorphologic features, and the judicious use of immunohistochemistry can allow an accurate diagnosis of metastatic Leydig cell tumor.