Prognostic factors of a large retrospective series of mucinous borderline tumors of the ovary (excluding peritoneal pseudomyxoma)

Background: To determine the prognosis and prognostic factors in a large series of mucinous borderline tumors of the ovary (MBOT). Materials and Methods: A retrospective review of patients with MBOT treated or referred to our institution. Three inclusion criteria were defined: (1) centralized histological review by our expert pathologist, (2) exclusion of peritoneal pseudomyxoma and any synchronous malignant tumor in the abdominal cavity, and (3) available data on the management and outcomes of patients. Results: From 1997 to 2004, 97 patients fulfilled inclusion criteria (95 stage I and 2 stage II disease). Of these, 9 patients had endocervical-like subtypes, 8 patients had stromal microinvasion, and 24 had intraepithelial carcinoma. Radical and conservative surgeries were performed, respectively, in 28 and 69 patients. After a median follow-up of 48 months, 13 patients had developed 14 recurrences: 7 were borderline and 7 were invasive lesions. The probability of recurrence in the form of carcinoma 5 and 10 years after the diagnosis was, respectively, 9 and 13%. The only prognostic factor for recurrence attaining statistical significance was the use of a cystectomy (compared with other surgeries relative risk [RR] = 5.6; P = 0.003; compared with salpingo-oophorectomy RR = 5.5; P = 0.012). Conclusions: In the present series of 97 MBOT, mainly early-stage disease and excluding peritoneal pseudomyxoma, the cumulative risk of recurrence in the form of invasive carcinoma at 10 years was 13%. MBOT do not appear to be such a "safe" disease. The only prognostic factor for recurrence was the use of a cystectomy, suggesting that a salpingo-oophorectomy should be preferred in cases of conservative treatment.