Objective The aim of this study was to estimate surgical outcome and survival benefit after completion surgery.

Methods We evaluated 164 patients with epithelial ovarian cancer who underwent incomplete primary cytoreductive surgery or rather received only staging procedures from January 2000 to December 2014 in outside institutions. Patient-related data were registered in prospective database of Tumor Bank Ovarian Cancer. The outcome analyses were performed for early and advanced stages of ovarian cancer separately.

Results The majority of patients were at the time of completion surgery in advanced stages of disease. From overall 111 advanced epithelial ovarian cancer patients, 74 (66.6%) could be operated macroscopically tumor free, minimal residual disease 1 cm or less was achieved in 15.3% of the cases. Mean overall survival for patients without versus those with any tumor residual was 70 months (95% confidence interval, 61.3–81.5) versus 24.7 months (95% confidence interval, 7.1–42.4; P ⩽ 0.0001). After applying completion surgery, 47 (28.6%) and 12 (6.7%) patients were upstaged in FIGO (International Federation of Gynecology and Obstetrics) IIIC and IV stages, respectively. Upstaging resulted in therapy changes in 10 patients (19%) with assumed FIGO IA stages. Major operative complications were registered in 28.8% of advanced cases, and 30-day mortality reached 1.8%.

Conclusions Recent research has shown that the most profound impact on survivorship occurs when women get proper care from surgeons trained in the latest techniques for treating ovarian cancer. Completion surgery maintained that even after initial incomplete cytoreduction outside of the high specialized units, after applying appropriate surgery techniques macroscopically, disease-free situation is achievable and outcomes are comparable with the results of primary debulking surgery.