Triple Threat: Co-occurrence of Serous Borderline Ovarian Tumor, Endometrial Adenocarcinoma, and Low-Grade Appendiceal Mucinous Neoplasms With Pseudomyxoma Peritonei in a Single Patient.

Borderline ovarian tumors (BOTs) are epithelial ovarian neoplasms characterized by cellular proliferation and nuclear atypia without stromal invasion. On the other hand, low-grade appendiceal mucinous neoplasms (LAMNs) have features such as mucin production, a distinct invasion pattern, and low-grade cytological characteristics. Pseudomyxoma peritonei (PMP), an uncommon disorder characterized by mucinous peritoneal dispersion, can be exacerbated by both BOTs and LAMNs. We present a case of a 63-year-old patient who was diagnosed with a serous BOT, LAMN with PMP, and synchronous endometrioid endometrial cancer. After episodes of postmenopausal bleeding, an explorative curettage confirmed the diagnosis of endometrioid endometrial cancer. Since the preoperative ultrasound showed a tumorous mass in the right adnexa and retrouterine space, the patient had an explorative laparotomy. A right ovarian tumor, hepatic and omental deposits, and an appendiceal lesion were among the intraoperative findings. A hysterectomy was performed along with peritoneal biopsy, cytological analysis of peritoneal lavage, bilateral salpingo-oophorectomy, omentectomy, lymphadenectomy, and appendectomy. Histopathological examination verified the presence of BOT, LAMN with PMP, and endometrial cancer. This case highlights the diagnostic difficulties of synchronous gastrointestinal and gynecological neoplasms and emphasizes the significance of a multidisciplinary surgical approach and thorough preoperative examination. According to our knowledge, this is the first case of synchronous endometrial cancer, serous BOT, and LAMN with PMP.