Advanced Ovarian Cancer: Primary or Interval Debulking? Five Categories of Patients in View of the Results of Randomized Trials and Tumor Biology: Primary Debulking Surgery and Interval Debulking Surgery for Advanced Ovarian Cancer

Background. Standard treatment of stage III and IV advanced ovarian cancer (AOC) consists of primary debulking surgery (PDS) followed by chemotherapy. Since the publication of the European Organisation for Research and Treatment of Cancer/National Cancer Institute of Canada trial, clinical practice has changed and many AOC patients are now treated with neoadjuvant chemotherapy (NACT) followed by interval debulking surgery(IDS). The best option remains unclear. Ovarian cancer is a heterogenic disease. Should we use the diversity in biology of the tumor and patterns of tumor localization to better stratify patients between both approaches? Methods. This analysis was based on results of five phase III randomized controlled trials on PDS and IDS in AOC patients, three Cochrane reviews, and four meta-analyses. Results. There is still no evidence that NACT-IDS is superior to PDS. Clinical status, tumor biology, and chemosensitivity should be taken into account to individualize surgical approach. Nonserous (type 1) tumors with favorable prognosis are less chemosensitive, and omitting optimal PDS will lead to less favorable outcome. For patients with advanced serous ovarian cancer (type 2) associated with severe comorbidity or low performance status, NACT-IDS is the preferred option. Conclusion. We propose stratifying AOC patients into five categories according to patterns of tumor spread (reflecting the biologic behavior), response to chemotherapy, and prognosis to make a more rational decision between PDS and NACT-IDS.