LAUSR

Abstract Background: The surgical treatment of advanced ovarian cancer aims to resect all visible tumor to no gross residual, these procedures are often extensive with need of prolonged attention to detail. Our objective was to investigate the association between week-day of surgery, time of year (season) when surgery was performed and non-radical surgery (surgical failure) in advanced ovarian cancer. Material and methods: Women diagnosed with primary invasive epithelial ovarian cancer in the Stockholm/Gotland Region, Sweden were identified in the regional Swedish Quality Registry of Gynecologic Cancer (SQRGC). Data of all women with International Federation of Gynecology and Obstetrics (FIGO) stages III and IV were validated against the National Cancer Registry. Women subjected to surgery with curative intent were selected and included in the analysis. Uni- and multivariable regression analyses were performed. Results: Out of 538 women identified in the SQRGC-string ovary between 2014 and 2016, 240 were eligible for analysis. In 29% of women, complete radical resection was not achieved. There was a significant trend of increased non-radical resection when surgery was performed from Monday through Thursday (p = .03). The adjusted odds of non-radical surgery increased if surgery was performed on Thursday rather than Monday (Odds Ratio (OR) 3.04, 95% Confidence Interval (CI) 1.05–8.79, p = .04). Surgery performed during summer compared to the rest of the year, did not significantly increase the adjusted odds of non-radical surgery (OR 1.92, 95% CI 0.91–4.07, p = .09). Conclusion: Complete surgical resection of tumor is one of the strongest prognostic factors for survival in advanced epithelial ovarian cancer. For this reason, advanced ovarian cancer surgery should be scheduled early in the week.