Primary appendiceal mucinous neoplasm: Gynecological manifestations, management, and prognosis

The aim of this study was to investigate the clinicopathological characteristics, management, and survival of patients with appendiceal mucinous neoplasm misdiagnosed as ovarian tumor and initially treated by a gynecological oncologists.

We retrospectively reviewed data for 71 patients identified from January 1, 2006 to September 31, 2018 with a final pathological diagnosis of appendiceal mucinous neoplasm. All patients were diagnosed as having ovarian tumor preoperatively and initially treated at Department of Gynecological Oncology.

The median patients' age was 61 years, and the median peritoneal cancer index (PCI) was 16, with a complete cytoreduction score (CCR0/1) achieved in 46.47% of patients. Two patients received hyperthermic intraperitoneal chemotherapy (HIPEC). Estimated 5-year and 10-year survival was 76.7% and 53.4%, respectively. PCI and lactate dehydrogenase (LDH) levels were identified as independent predictors of poor overall survival.

Because of the high rate of ovarian metastases and the difficulty diagnosing appendiceal mucinous neoplasm preoperatively, this condition should be highlighted in gynecological oncology. Because initial surgical intervention is often performed by gynecological oncologists, updating the management guidelines for appendiceal mucinous tumor is needed because the rates of CCR0/1 resection and HIPEC are much lower in patients who are misdiagnosed.