A new report led by researchers at the American Cancer Society (ACS) shows, during the first year of the COVID-19 pandemic, cancer incidence rates declined for almost all cancer types examined. The declines were largely driven by local and regional stage disease, however, cancer incidence rates for distant stage or the most advanced type of disease decreased for just six of the 22 cancer types examined. The study is published November 16 in the International Journal of Cancer.

“Cancer incidence rates during 2020 deviated from pre-pandemic patterns, likely due to the suspension of health care for both cancer and non-cancer related medical care,” said Elizabeth Schafer, associate scientist, health equity science at the American Cancer Society and lead author of the study. “These findings have given us more evidence of the impact of the pandemic on cancer incidence rates by stage at diagnosis and race and ethnicity.”

For this cross-sectional report, researchers calculated delay- and age-adjusted incidence rates, stratified by stage at diagnosis and race and ethnicity, and rate ratios. Scientists compared changes in year-over-year incidence rates from 2016 to 2020 for 22 cancer types based on data obtained from the Surveillance, Epidemiology, and End Results (SEER) 22-registry database.

The study results showed, from 2019 to 2020, the incidence of local-stage disease declined for 19 of the 22 cancer types, ranging from 4% for urinary bladder cancer to 18% for colorectal and laryngeal cancers, deviating from pre-COVID stable year over-year changes. Incidence during the corresponding period also declined for 16 cancer types for regional-stage and six cancer types for distant-stage disease. By race and ethnicity, the decline in local-stage incidence for screening-detectable cancers was generally greater in historically marginalized populations. The decline in cancer incidence rates during the first year of the COVID-19 pandemic occurred mainly for local and regional-stage diseases across racial and ethnic groups.

“Whether these declines will lead to increases in advanced-stage disease and mortality rates remain to be investigated by studying the incidence and mortality trends with additional data years,” added Schafer. “Nevertheless, the findings reinforce the importance of strengthening the return to preventive care campaigns and outreach for detecting cancers at early and more treatable stages.”

Dr. Ahmedin Jemal is senior author of the paper. Other ACS authors include Dr. Farhad Islami, Dr. Xuesong Han, Dr. Leticia Nogueira, Dr. Nikita Sandeep Wagle, Dr. Robin Yabroff and Dr. Hyuna Sung.

This press release was originally published November 16, 2023, by the American Cancer Society. It is republished with permission.