Minimal impact of COVID-19 on one-year mortality on U.S. cancer patients diagnosed early in the pandemic

Abstract Cancer patients diagnosed early in the COVD-19 pandemic may have been particularly vulnerable due to immunosuppression caused by their cancer. The objective was to assess cause of death due to COVID-19, cancer and other causes among cancer patients during the pandemic. We thus examined causes of death (cancer, COVID-19, other causes) among cancer patients diagnosed in 2020 (N=503,128) compared to 2018 (N=537,006) in the Surveillance, Epidemiology, and End Results (SEER)-22. We focused on 1-year cause-specific mortality by cancer type, stage and age at diagnosis. In a counterfactual analysis we estimated the number and proportions of cancer patients dying from cancer or other competing causes if COVID-19 were eliminated as a possible cause of death. Among 2020 cancer patients, 15.8% died from cancer, 3.3% from other causes, and 0.7% from COVID-19. Among those who died, COVID-19 mortality was 9%, 7.6%, 2.8%, 2.8% and 1.2% of all deaths for prostate, breast, colorectal, lung, and pancreatic cancer, respectively. In a counterfactual analysis assuming that COVID-19 had not occurred, similar percentages would have died from cancer or other causes, except for lung and pancreatic cancer. In summary, cancer was the leading cause of death in 2020, but COVID-19 did not have a large influence on competing-cause mortality. These findings inform healthcare strategies to mitigate excess mortality among cancer patients during future healthcare disruptions.