To explore the clinicopathologic features and prognosis of female appendiceal mucinous tumor misdiagnosed as gynecological neoplasm.

The clinical data of 12 cases of suspected gynecological neoplasm but confirmed as appendiceal mucinous tumor by operation and pathology in Beijing Obstetrics and Gynecology Hospital hospital from 2010 to 2019 were collected. The clinicopathologic features, treatment and prognosis of these patients were analyzed.

The median age of 12 patients was 58 years old and the clinical manifestations were atypical, including 5 cases with gastrointestinal symptoms, 6 cases with touched lesion in the right adnexal area, 3 cases with pseudomyxoma of peritonei, and 4 cases with increased serological tumor markers and ascites. Before operation, ultrasonic diagnosis showed cystic or cystic-solid mass in the right adnexal region in all cases. Pelvic and abdominal enhanced CT and/or enhanced MRI were performed in 5 cases. Two cases indicated possible origin of appendix and 1 case indicated lymphatic cystic tumor. Laparoscopic or laparotomy exploration was performed in all patients, during the operation 7 cases were performed appendectomy, 4 cases were performed tumor cell reduction and 1 case was treated in another hospital after laparotomy exploration. Eleven cases were diagnosed as low-grade appendiceal mucinous tumor and 1 case as appendiceal mucinous adenocarcinoma by postoperative pathology. Among the 11 patients with low-grade appendiceal mucinous tumor, 9 cases had no recurrence, 1 case lost follow-up, 1 case died of breast cancer and 1 case died 18 months after the operation.

Gynecologists should improve their ability to differentiate appendiceal mucinous tumor from gynecological neoplasm. They can include ultrasonic diagnosis and CT scanning into their preoperative physical examination to improve their examination ability, and strive for specialist or surgical treatment to achieve the best result.

Gynecological neoplasms; Appendiceal mucinous neoplasms; Pseudomyxoma peritonei; Misdiagnosis