Ultra-radical upfront surgery does not improve survival in women with advanced epithelial ovarian cancer; a natural experiment in a complete population.

OBJECTIVE:Ultra-radical surgery to achieve complete resection in advanced epithelial ovarian cancer (EOC) has been widely accepted without strong supporting data. Our objective was to assess overall survival after a structured shift to an ultra-radical upfront surgical treatment algorithm and to investigate changes in the distribution of primary treatments after this shift. PATIENTS AND METHODS:In this population-based cohort study, all women with suspected EOC in the Stockholm-Gotland region of Sweden reported to the Swedish Quality Registry for Gynecologic Cancer (SQRGC) and National Cancer Registry (NCR) were selected in two 3-year cohorts, based on year of diagnosis (before (cohort1) or after (cohort 2) change in surgical treatment algorithm) and followed for at least three years. 5-year overall survival (OS) in non-surgically and surgically treated women was analyzed. Moreover, proportional distribution of primary treatment was evaluated. RESULTS:752 women were included in the final analysis (n = 364 and 388 in cohort 1 and 2 respectively) with a median follow-up of 29 and 27 months. The complete resection rate increased from 37 to 67% (p ≤ 0.001) as well as proportion non-surgically treated women, 24 to 33%. No improvement in OS was observed in non-surgically (HR 0.76 (95% CI, 0.58-1.01); p = 0.06) or surgically treated (HR 0.94 (95% CI, 0.75-1.18); p = 0.59) women, even when complete resection was achieved (HR 1.31 (95% CI, 0.89-1.92); p = 0.17). CONCLUSION:A shift to ultra-radical upfront surgery in EOC did not improve survival despite a significant increase in complete resection rate. Identifying the limitations of surgical treatment remains a challenge.