Objectives Similar to primary debulking surgery, complete resection of all macroscopic diseases during interval debulking surgery (IDS) is the primary objective while using neoadjuvant chemotherapy followed by IDS for advanced ovarian, fallopian tube, and peritoneal cancers. However, most patients develop recurrent disease even after complete cytoreduction during IDS. This study aims to identify recurrence patterns of the ovarian, fallopian tube, and peritoneal cancers in patients who underwent complete cytoreduction during IDS.

Methods We retrospectively reviewed data of patients with stage III or IV ovarian, fallopian tube, and peritoneal cancers who were treated at our hospital from January 1, 2005, to December 31, 2011.

Results In this study, 105 patients underwent neoadjuvant chemotherapy followed by IDS and achieved complete cytoreduction. The median follow-up period was 42.1 months. Recurrence was documented in 70 patients (66.7%), and 35 (33.3%) showed no evidence of disease. Peritoneal dissemination was the most common recurrence (60.0%) observed. In multivariate analysis, positive peritoneal cytology (P = 0.0003) and elevated pre-IDS serum CA125 levels (P = 0.046) were independent risk factors for recurrence.

Conclusions After complete cytoreduction during IDS in patients with stage III or IV ovarian, fallopian tube, and peritoneal cancers, positive peritoneal cytology at IDS and elevated pre-IDS CA125 levels are associated with an increased risk of cancer recurrence. Positive peritoneal cytology during IDS is a particularly strong predictive factor for poor outcomes in these patients.