Bilateral borderline ovarian brenner tumor coexisting with low-grade appendiceal mucinous neoplasm in a perimenopausal woman: a case report
Borderline ovarian Brenner tumor (BOT-B) accounts for less than 2% of all ovarian neoplasms. It is typically unilateral and large, with non-specific imaging features. Synchronous extra-ovarian neoplasia is rarely documented. A 47-year-old gravida 2, para 2 woman presented with intermenstrual bleeding and lower abdominal discomfort. Transvaginal ultrasound and pelvic magnetic resonance imaging (MRI) revealed a 9 cm right adnexal complex mass without ascites or elevated serum tumor markers. Intraoperative findings identified bilateral, firm, lobulated ovarian tumors (right: 5 cm; left: 7 cm) and an inflamed, hydropic appendix. Frozen section analysis of the left ovary indicated a borderline Brenner tumor with focal atypia; carcinoma could not be ruled out. Following informed consent, the patient underwent laparoscopic bilateral salpingo-oophorectomy, appendicectomy, omentectomy, and peritoneal biopsy. Final histopathology confirmed bilateral BOT-B without stromal invasion and a synchronous low-grade appendiceal mucinous neoplasm (LAMN) with negative margins. No adjuvant chemotherapy was administered. Imaging at three-month follow-up showed no evidence of recurrence. This represents the first reported case of synchronous bilateral BOT-B and LAMN. It highlights the following: i) the critical importance of comprehensive surgical exploration for atypical adnexal masses; ii) that BOT-B can present bilaterally and at a smaller size than classically described; and iii) that complete, conservative fertility-sparing surgery with strict adherence to a tumor-free technique is an adequate management strategy for borderline Brenner tumors, associated with excellent short-term outcomes.