Sertoli-Leydig Cell Tumor and High-Grade Serous Carcinoma Collision Tumor of the Ovary- Report of the Second Case

Background The term collision tumor is used when two unique neoplasms occur in the same organ at the same time. Ovarian collision tumors are extremely rare with different combinations of the following tumors being cited in the literature: surface epithelial tumors, sex-cord stromal tumors, and germ cell tumors. While several cases of combined mucinous neoplasms and granulosa cell tumors have been identified, only one collision case of Sertoli Leydig Cell Tumor (SLCT) and high-grade serous carcinoma (HGSC) has been published (1-6). Methods This case report, diagnosed in late 2022, includes the presentation, clinical management, and ultimately pathologic diagnosis of a rare collision tumor of the ovary composed on SLCT and HGSC. Results A 70 year old female, G4P4 presented to an outside emergency department for an episode of lightheadedness, dizziness, fatigue, and muscle weakness. Her blood pressure was elevated in the 200s and she was diagnosed with malignant hypertension. Her primary care provider worked her up for adrenal masses with a CT scan and she was referred to gynecologic oncology. On physical exam at her referral, her abdomen was soft and nondistended. A small umbilical hernia was noted. Her CA-125 was 578 units/mL and testosterone 99.40 ng/dL. CT, transvaginal ultrasound, and a PET scan all confirmed extensive peritoneal carcinomatosis including omental caking, mesenteric nodules, and posterior pelvic peritoneal mass and a complex 5.0 cm solid cystic right ovarian lesion, suspicious for malignancy. Additionally, a small volume of abdominopelvic free fluid was identified. These findings were consistent with a peritoneal carcinomatosis. The patient was taken for diagnostic laparoscopy, right salpingo-oophorectomy, and biopsies of the omentum and pelvic peritoneum. In the OR, 1-4mm nodules scattered throughout the pelvic and abdominal peritoneum, small bowel mesentery, and diaphragm were noted. Pathologic review confirmed a poorly differentiated SLCT of the right ovary (Stage IIIIC- pT3C Nx M0) with metastasis to the omentum and right pelvic side wall. Additionally, the right ovary was positive for HGSC metastatic from the fallopian tube. After H&E examination immunostains for p53, napsin, PAX8, synaptophysin, CD56, and inhibin were ordered with adequate controls. Tumor cells corresponding to poorly differentiated SLCT were positive for p53, CD56, and inhibin, while negative for PAX8, napsin, and synaptophysin. The metastatic HGSC was only positive for PAX8 and p53. Discussion Serous carcinoma of the fallopian tube is the most common form of ovarian cancer. SLCT are rare and typically found with Stage I disease. Stage III or IV are especially rare and there is little known on these neoplasms presenting at an advanced stage. The mechanism of collision tumor development has many hypotheses, though the most straight forward theory is that each tumor develops independently of the other and by chance collides into the other (7). Conclusion SLCT are rare neoplasms seen even more rarely with a concurrent tumor in the ovary. Additionally, an advanced stage SLCT makes this case even more unexpected. More research needs to be done to further understand collision tumors of the ovary and their associated findings, prognosis, and development.