Increased disease-free and relative survival in advanced ovarian cancer after centralized primary treatment.

ABSTRACT

OBJECTIVE: To analyze 5-year disease-free survival (DFS) and relative survival (RS) before and after the 2011 implementation of centralized primary treatment of patients with advanced ovarian cancer. METHODS: A population-based cohort study using the Swedish Quality Registry for Gynecological Cancer (SQRGC). Women with FIGO stage III and IV epithelial ovarian and Fallopian tube cancers were divided into two cohorts before and after centralization. We estimated RS using the Ederer II method, analyzed the difference in the excess mortality rate ratio (EMRR) and estimated 5-year DFS in a Cox proportional hazard regression model with centralization, age, primary treatment and complete cytoreduction as variables. RESULTS: A total of 495 women were identified with 244 women before (2008-2010) and 251 after (2011-2013) centralization. An increased 5-year RS from 24% (95%CI19-31) to 37% (95%CI31-44) and an increased median RS from 27 months (95%CI23-34) to 44 months (95%CI40-52), p < 0.001 (log-rank), were observed in the total cohort regardless of primary treatment. EMRR was found to be 0.62 (95%CI0.51-0.76) in 2011-2013 compared to 2008-2010 for all patients. After centralization, 5-year DFS was significantly longer, hazard ratio of 0.77 (95%CI0.64-0.93) and centralization was found to be an independent significant factor for both survival and DFS. Complete cytoreduction was found to be a significant independent factor associated with increased RS and DFS. CONCLUSION: Centralization of primary treatment of advanced ovarian cancer was associated with significantly increased complete cytoreduction, 5-year RS and DFS, and was found to be a significant independent factor for both RS and DFS.