Impact of pattern of recurrence on post-relapse survival according to surgical timing in patients with advanced ovarian cancer

Objective Our study aimed to evaluate the association between timing of cytoreductive surgery and pattern of presentation of the first recurrence in patients with advanced ovarian cancer. We also aimed to assess the impact of the pattern of recurrence on post-relapse overall survival according to surgical timing. Methods This retrospective multicenter study evaluated patients with International Federation of Gynecology and Obstetrics (FIGO) stage IIIC-IV ovarian cancer. Patients had undergone either primary debulking surgery, early interval debulking surgery after 3–4 cycles of neoadjuvant chemotherapy, or delayed debulking surgery after 6 cycles, with minimal or no residual disease, between January 2008 and December 2015. Survival analyses were conducted using the Log-rank test and the Cox model. Cumulative incidences of the different patterns of recurrence were estimated using a competing risks methodology. Results A total of 549 patients were included: 175 (31.9%) patients had primary, 224 (40.8%) early interval, and 150 (27.3%) delayed debulking surgery. The cumulative incidence of peritoneal recurrences at 2 years was higher with increasing neoadjuvant cycles (24.4%, 30.9% and 39.2%; p=0.019). For pleural or pulmonary recurrences, it was higher after early interval surgery (9.9%, 13.0% and 4.1%; p=0.022). Median post-relapse overall survival was 33.5 months (95% confidence interval (CI) (24.3 to 44.2)), 26.8 months (95% CI (22.8 to 32.6)), and 24.5 months (95% CI (18.6 to 29.4)) for primary, early interval, and delayed debulking surgery groups, respectively (p=0.025). The pattern of recurrence in a lymph node (hazard ratio (HR) 0.42, 95% CI (0.27 to 0.64)), delayed surgery (HR 1.53, 95% CI (1.11 to 2.13)) and time to first recurrence (HR 0.95, 95% CI (0.93 to 0.96)) were associated with post-relapse overall survival. For primary and early interval surgery, lymph node recurrences were associated with significantly longer post-relapse overall survival. Conclusions The pattern of first recurrence was associated with timing of surgery, with peritoneal recurrences being more frequent with the increasing number of cycles of neoadjuvant chemotherapy. Lymph node recurrences were associated with better prognosis, having higher post-relapse overall survival. This improved prognosis of lymphatic recurrences was not observed in patients who underwent delayed surgery.