Survival impact of surgical cytoreduction in stage IV epithelial ovarian cancer.

OBJECTIVE: The aim of this study was to evaluate the influence of surgical cytoreduction on survival in patients with Stage IV epithelial ovarian cancer and to determine the survival impact of debulking extrahepatic disease in the subgroup of patients with liver metastasis.
METHODS: Medical records were retrospectively reviewed for all women with International Federation of Gynecology and Obstetrics Stage IV ovarian cancer treated between 1/1/82 and 12/31/94. Clinical information abstracted included age at diagnosis, performance status, histologic subtype, tumor grade, Stage IV criteria, ascites volume, predominant peritoneal tumor pattern, surgical procedures performed, hepatic tumor residuum, extrahepatic tumor residuum, and postoperative complications. Optimal surgical status was defined as residual disease </=1 cm. Chemotherapy treatment and follow-up were recorded. Survival analysis and comparisons were performed using the Kaplan-Meier method and the log-rank test. The Cox proportional hazards regression model was used to identify independent variables associated with an improved survival rate.
RESULTS: There were 84 women with Stage IV ovarian cancer and complete operative and postoperative information available. Median age at diagnosis was 61 years (range 26-85 years). Performance status was </=2 in 83% of patients (70/84). Papillary serous histology was found in 44/84 patients (52%) and 55 patients (65%) had grade 3 tumors. Thirty-seven of 84 patients (44%) had parenchymal liver metastasis and 32/84 (38%) had malignant pleural effusion. Overall median survival was 18.1 months and was highly correlated with performance status (P = 0.002), predominant peritoneal tumor pattern (P = 0.0002), and the number of chemotherapy regimens received (P = 0.0039). Primary surgical cytoreduction was attempted in all patients and 25/84 (30%) achieved optimal status. Median survival of optimally cytoreduced patients was 38.4 months, compared to 10.3 months for patients with suboptimal residual disease (P = 0.0004). In patients with liver metastasis, optimal extrahepatic cytoreduction was achieved in 46% (17/37). Six of 37 patients (16%) underwent optimal resection of both extrahepatic and hepatic disease and had a median survival of 50.1 months, compared to a median survival of 27.0 months for the 11 patients (30%) with optimal extrahepatic disease but suboptimal residual hepatic tumor. Twenty patients (54%) were left with both suboptimal residual extrahepatic and hepatic disease and had a median survival of 7.6 months (P = 0.0001). Optimal debulking surgery and performance status retained significance as independent predictors of survival on multivariate analysis.
CONCLUSIONS: Optimal surgical debulking and performance status appear to be important determinants of survival in patients with Stage IV epithelial ovarian cancer. Even in patients with unresectable liver metastasis, optimal debulking of extrahepatic disease is associated with a significant survival advantage. Copyright 1999 Academic Press.