Factors Predicting 30-Day Grade IIIa-V Clavien-Dindo Classification Complications and Delayed Chemotherapy Initiation after Cytoreductive Surgery for Advanced-Stage Ovarian Cancer: A Prospective Cohort Study.

Objective : The aim of this study was to evaluate factors associated with 30-day postoperative Clavien-Dindo classification (CDC) grade IIIa or greater complications and delayed initiation of chemotherapy after cytoreductive surgery (CRS) for primary advanced-stage epithelial ovarian cancer (AEOC). Methods: This was a prospective study involving 300 patients who underwent primary or interval CRS for AEOC between February 2018 and September 2020. Postoperative complications were graded according to the CDC. Logistic regression analysis was used to evaluate factors predicting CDC grade ≥IIIa and time to chemotherapy (TTC) >42 days. Results: Interval CRS was performed in 255 (85%) patients. CDC grade ≥IIIa occurred in 51 (17%) patients. In multivariable analysis, age ( p = 0.036), cardiovascular comorbidity ( p < 0.001), diaphragmatic surgery ( p < 0.001), intraoperative urinary tract injury ( p = 0.017), and upper-abdominal visceral injury (e.g., pancreas, stomach, liver, or spleen) ( p = 0.012) were associated with CDC grade ≥IIIa. In 26% of cases, TTC was >42 days (median (IQR) 39 (29-50) days) in patients with CDC grade ≥IIIa versus 33 (25-41) days in patients without CDC grade ≥ IIIa ( p = 0.008). The adjusted odds ratio of developing TTC >42 days was significantly higher in patients associated with WHO performance grade ≥2 ( p = 0.045), intraoperative bowel injury ( p = 0.043), upper-abdominal visceral injury ( p = 0.008), and postoperative CDC grade ≥IIIa ( p = 0.032). Conclusions : Patients with advanced age, with cardiovascular comorbidity, and who required diaphragmatic surgery had an increased adjusted odds ratio of developing CDC grade ≥IIIa complications. CDC grade ≥IIIa complications were independently associated with TTC >42 days. Proper patient selection and prevention of intraoperative injury are essential in order to prevent postoperative complications and delayed initiation of chemotherapy.