Preoperative COVID-19 and Postoperative Mortality in Cancer Surgery: A South Korean Nationwide Study

We evaluated the impact of preoperative COVID-19 on early postoperative mortality in patients undergoing time-sensitive cancer surgery. This retrospective, nationwide cohort study included adult patients who underwent various cancer (thyroid, breast, stomach, colorectal, hepatobiliary, genitourinary, lung, and multiple cancer) surgeries under general anesthesia in South Korea in 2022. Patients were grouped according to the duration from the date of COVID-19 confirmation to the date of surgery (0–2 weeks, 3–4 weeks, 5–6 weeks, and ≥7 weeks). Patients without preoperative COVID-19 also were included. Multivariable logistic regression analysis with Firth correction was performed to investigate the association between preoperative COVID-19 and 30-day and 90-day postoperative mortality. The covariates encompassed sociodemographic factors, the type of surgery, and vaccination status in addition to the aforementioned groups. Of the 99,555 patients analyzed, 30,933 (31.1