Continuous improvement in primary Debulking surgery for advanced ovarian cancer: Do increased complete gross resection rates independently lead to increased progression-free and overall survival?

OBJECTIVES: To assess complete gross resection (CGR) rates and survival outcomes in patients with advanced ovarian cancer who underwent primary debulking surgery (PDS) during a 13-year period in which specific changes to surgical paradigm were implemented. METHODS: We identified all patients with stage IIIB-IV high-grade ovarian carcinoma who underwent PDS at our institution, with the intent of maximal cytoreduction, from 1/2001-12/2013. Patients were categorized by year of PDS based on the implementation of surgical changes to our approach to ovarian cancer debulking (Group 1, 2001-2005; Group 2, 2006-2009; Group 3, 2010-2013). RESULTS: Among 978 patients, 78% had stage IIIC disease and 89% had disease of serous histology. Carcinomatosis was found in 81%, and 60% had bulky upper abdominal disease (UAD). Compared to Group 1, those who underwent PDS during the latter 2 time periods had higher ASA scores (p < 0.001), higher-stage disease (p < 0.001), and more often had carcinomatosis (p = 0.015) and bulky UAD (p = 0.009). CGR rates for Groups 1-3 increased from 29% to 40% to 55%, respectively (p < 0.001). Five-year progression-free survival (PFS) rates increased over time (15%, 16%, and 20%, respectively; p = 0.199), as did 5-year overall survival (OS) rates (40%, 44%, and 56%, respectively; p < 0.001). On multivariable analysis, CGR was independently associated with PFS (p < 0.001) and OS (p < 0.001). CONCLUSIONS: Despite higher-stage disease and greater tumor burden, CGR rates, PFS and OS for patients who underwent PDS increased over a 13-year period. Surgical paradigm shifts implemented specifically to achieve more complete surgical cytoreduction are likely the reason for these improvements.