The impact of COVID-19 on the oncologic outcomes of 3236 patients undergoing ColoRectal Cancer surgery in Northern Italy in 2019 and 2020 (COVID-CRC): results of a multicentric comparative cohort study.

ObjectiveThis study compared all patients undergoing surgery for colorectal cancer in 20 hospitals of Northern Italy in 2019 versus 2020, in order to evaluate whether COVID-19-related delays in the execution of colorectal cancer screening resulted in more advanced cancers at diagnosis and worse clinical outcomes. DesignA retrospective multicentric cohort analysis of patients who underwent surgery for colorectal cancer in March-December 2019 (2019) versus March-December 2020 (2020). The independent predictors of disease stage (oncologic stage, associated symptoms, clinical T4 stage, metastasis) and postoperative outcome (surgical complications, palliative surgery, 30-day death) were evaluated using logistic regression. ResultsThe sample consisted of 1755 patients operated in 2019, and 1481 in 2020 (both mean ages 69.6 years). The proportions of cancers with symptoms, clinical T4 stage, liver and lung metastases in 2019 and 2020 were, respectively: 80.8% vs 84.5%; 6.2% vs 8.7%; 10.2% vs 10.3%; and 3.0% vs 4.4%. The proportions of surgical complications, palliative surgery, and death in 2019 and 2020 were, respectively: 34.4%vs 31.9%; 5.0% vs 7.5%; and 1.7% vs 2.4%. At multivariate analysis, as compared with 2019, cancers in 2020 were significantly more likely to be symptomatic (Odds Ratio - OR: 1.36, 95% Confidence Interval - CI: 1.09-1.69), in clinical T4 stage (OR: 1.38; 1.03-1.85), with multiple liver metastases (OR: 2.21; 1.24-3.94), but less likely to cause surgical complications (OR: 0.79; 0.68-0.93). ConclusionsColorectal cancer patients who had surgery between March and December 2020 had an increased risk of more advanced disease in terms of associated symptoms, cancer location, clinical T4 stage, and number of liver metastases. SHORT SUMMARY BOX What is already known about this subject?A specific search regarding the correlation between colorectal cancer oncologic outcomes and COVID-19 showed a few modeling studies which reported the predictions of the potential impact of the diagnostic delays (due to the reduction of the screening programs) on the survival of patients affected by colorectal cancer. However, no study reported any real-life evidence regarding the correlation between the COVID-19 outbreak and the deteriorations of the oncologic outcomes of patients with colorectal cancer. What are the new findings?The present study showed that patients who had surgery for colorectal cancer between March and December 2020 had an increased risk of more advanced disease in terms of associated symptoms, cancer location, clinical T4 stage, and number of liver metastases, than patients who had surgery between March and December 2019. How might it impact on clinical practice in the foreseeable future?The present study confirmed that the backlogs of the screening programs have had, and probably will have, detrimental effects on the oncologic outcomes of patients affected by colorectal cancer. Increased resources should be placed in order to reactivate and enhance the screening programs, and to reduce the risk of colorectal cancer patients to be diagnosed with advanced cancer in the next future.