Introduction/Background A 27-year-old female patient with cerebral palsy and epilepsy was admitted due to abdominal swelling that had increased in the last six months. On CT, an ovarian mass extending from the pelvis to the left upper quadrant, 234 mm in diameter, multiseptated, multiloculated, with cystic and solid components, was observed. The AFP level in the blood was 1210 ng/ml and the CA125 level was 132 units/mL.

Methodology Under general anesthesia, the abdomen was entered through an incision made in the middle. No tumor was found in the liver, spleen, small intestine, colon, mesentery and omentum. The dilated gonadal vein, surrounded by multiple bulky lymph nodes, was excised to the origin of the inferior vena cava. At this point, it was clamped and cut. A multicystic mass originating from the right ovary, measuring 33^*30 cm, weighing 7600 grams, and containing solid areas was removed from the abdomen with the capsule intact. Pelvic and para-aortic lymphadenectomy and omentectomy were added to the procedure. Due to the patient‘s desire for fertility, a normal-looking left ovary and uterus were left.

Results The patient was discharged on the 4th postoperative day without any complications. Final pathology revealed a moderately differentiated Sertoli-Leydig cell tumor containing heterologous elements. Heterologous elements containing gastrointestinal-type epithelium and areas showing focal neuroendocrine differentiation were observed in the tumor. Lymph node involvement and lymphovascular invasion were not observed.

Conclusion Sertoli-Leydig cell tumor is a differentiated sex cord-stromal tumor of the ovary. It is seen at a young age and is rare. Most patients are diagnosed at an early stage. Histology is usually low grade and lymph node metastasis is rare. The definitive diagnosis is made by a final pathological examination.

Disclosures In the current video, we present a fertility-sparing operation for a gross Sertoli-Leydig cell tumor.