PurposeWith the onset of the COVID pandemic in Germany in March 2020, far-reaching restrictions were imposed that limited medical access for patients. Screening examinations such as colonoscopies were greatly reduced in number. As rapid surgical triage after diagnosis is prognostic, our hypothesis was that pandemic-related delays would increase the proportion of advanced colon cancers with an overall sicker patient population.MethodsA total of 204 patients with initial diagnosis of colon cancer were analyzed in this retrospective single-center study between 03/01/2018 and 03/01/2022. Control group (111 patients, pre-COVID-19) and the study group (93 patients, during COVID-19) were compared in terms of tumor stages, surgical therapy, complications, and delays in the clinical setting. The data were presented either as absolute numbers or as median for constant data.ResultsA trend towards more advanced tumor stages (T4ap= 0.067) and a significant increase of emergency surgeries (p= 0.016) with higher rates of ileus and perforation (p= 0.004) as well as discontinuity resections (p= 0.049) during the pandemic could be observed. Delays in surgical triage after endoscopic diagnosis were seen during the 2nd lockdown (02/11/20–26/12/20;p= 0.031).ConclusionIn summary, the results suggest delayed treatment during the COVID-19 pandemic, with the infection pattern of COVID appearing to have a major impact on the time between endoscopic diagnosis and surgical triage/surgery. Adequate care of colon cancer patients is possible even during a pandemic, but it is important to focus on structured screening and tight diagnosis to treatment schedules in order to prevent secondary pandemic victims.