Heterogeneity in Stage IV Ovarian Cancer: Survival Trends in Patients Presenting with Sister Mary Joseph's Nodule

Background/Objectives: Sister Mary Joseph's nodule (SMJN) is classified as FIGO stage IVb in ovarian cancer. While traditionally considered an indicator of poor prognosis, emerging evidence suggests variable outcomes. This study aimed to describe overall survival (OS) and recurrence-free survival (RFS) in ovarian cancer patients presenting with SMJN and to explore outcome patterns relative to other FIGO IVb presentations. Methods: We conducted a retrospective multicenter cohort study including patients with epithelial ovarian, fallopian tube, or primary peritoneal carcinoma diagnosed between 2010 and 2023 at four academic centers in Switzerland, Italy, and Israel. Eligible patients had FIGO IV disease at diagnosis and complete clinical data. Patients were grouped according to metastatic pattern: SMJN or other distant sites. Survival outcomes were analyzed using Kaplan-Meier curves and Cox proportional hazards models. Results: Eighty-seven patients met inclusion criteria, including 23 (26.4%) with SMJN and 64 (73.6%) with other FIGO IV metastases. Median age and histologic subtype distribution were similar between groups. Complete cytoreduction was achieved in 65.2% of SMJN patients. Median OS was not reached in the SMJN group versus 47.2 months in controls (HR 0.44; 95% CI 0.17-1.12; p = 0.084). Median RFS was 42.6 vs. 23.2 months, respectively (HR 0.68; 95% CI 0.35-1.32; p = 0.25). Conclusions: Patients presenting with SMJN may represent a potentially resectable manifestation within the heterogeneous spectrum of FIGO stage IV ovarian cancer, with a non-significant trend toward more favorable survival outcomes compared with other stage IV presentations.