Risk Prediction Model for Surgical Complications and Predictors of Delay/Omission of Adjuvant Chemotherapy Post Primary Cytoreduction in Epithelial Ovarian Cancer

A risk prediction model for surgical complications post-primary cytoreduction in epithelial ovarian cancer was developed along with determination of factors causing delay/omission of adjuvant chemotherapy. An ambi-directional cohort study was done, including stage II-IV epithelial ovarian, fallopian tube, and primary peritoneal carcinoma patients who underwent primary cytoreduction between January 01, 2016, and December 31, 2020. Clavien-Dindo classification was used to grade surgical complications. Adjuvant treatment was considered delayed if initiated >28 days of surgery. Modified Poisson regression method was used to estimate risk ratios (RR). Of 164 patients, 48 (29.2%) had grade III-V complications. Performance status of ECOG 2 (RR 3.27), surgical duration >= 4 h (RR 3.01), diaphragm stripping/resection (RR 2.05), and large bowel resection (RR 2.46) were independent risk factors. For an optimal score cutoff of >= 2.8, the discrimination between patients with and without complications was 80.0% (area under curve 0.80, p = 0.001). A risk model built using this score predicted major complications in 65% of cases. The median time to start adjuvant chemotherapy was 28 (10-77) days. Sixty-three (38.4%) patients had a delay, and 18 (10.9%) did not receive adjuvant treatment. Extended hospital stay (RR 1.08) and grade III-IV complications (RR 1.83) delayed chemotherapy, while low albumin (RR 2.15), postoperative ascites (RR 3.67), surgical site infections (RR 2.93), and poor social support (RR 2.70) resulted in omission. Performance status of ECOG 2 and prolonged surgery with diaphragmatic/large bowel resection predict major postoperative complications. Low albumin, grade III/IV complications, and extended hospital stay along with poor social support cause omission/delay in initiation of adjuvant chemotherapy.