Granulosa Cell Tumor Arising in the Paratesticular Area: A case report

ABSTRACT

Granulosa cell tumor of the testis is extremly rare in adult males and granulosa cell tumor occurring in the paratesticular area has not been reported. We report a paratesticular granulosa cell tumor in a 34-year-old man who presented with a 5.5 cm sized scrotal mass. The tumor was present in the paratesticular area near the head of epididymis. It was located in the tunica and completely separated from the testis by thick fibrous tissue. Microscopically, the tumor exhibited solid, microfollicular, and trabecular patterns. The tumor cells had ovoid to elongated nuclei with longitudinal intranuclear grooves and one or two nucleoli and scanty cytoplasm. Mitoses were relatively frequent with an average number of 9/10 HPFs. The tumor extended into the visceral tunica vaginalis and showed multiple lymphatic tumor emboli. Immunohisto chemical stains revealed diffuse strong positivity for inhibin, vimentin, and keratin and diffuse weak positivity for estrogen and progesteron receptor. Placental alkaline phosphatase (PLAP) and epithelial membrane antigen (EMA) were negative. On electron microscopic examination, tumor cells were polygonal and had large indented nuclei. The cytoplasm contained a moderate number of small round mitochondria, abundant rough and smooth endoplasmic reticula, and a few lipid droplets. Small aggregates of intermediate filaments and intercellular junctions were observed. The patient was alive and well 5 months after orchiectomy. This is the first case of adult granulosa cell tumor arising in the paratesticular area.