Changes in cancer diagnoses and stage distribution during the second year of the COVID-19 pandemic in the US.

130 Background: During 2020, the first year of the COVID-19 pandemic, cancer diagnoses decreased, especially early-stage disease, with largest decreases in medically underserved populations. It is unknown whether this pattern continued during 2021, the second year of the COVID-19 pandemic. With newly released cancer surveillance data, this study examined nationwide changes in adult cancer diagnoses and stage distribution from 2019 to 2021 in the US. Methods: Adults aged ≥18 years who were newly diagnosed with first primary malignant cancers between 2019 and 2021 from 50 US states and the District of Colombia were identified from the National Cancer Database. We calculated monthly cases, stage distribution, and adjusted odds ratios (aOR) of stage I vs. stage II–IV cancer and stage IV vs. stage I–III cancer diagnoses in 2021 compared with 2019, controlling for sociodemographic and clinical factors and stratified by cancer type. Results: We identified 864,430 individuals diagnosed in 2019, 780,478 diagnosed in 2020, and 819,791 diagnosed in 2021. The proportion of diagnoses at stage I decreased from 39.6% in 2019 to 31.1% in April 2020, and were 39.2% overall in 2021. The decrease in stage I diagnoses was mirrored by an increase in stage IV diagnoses. The pattern was most prominent for female breast, lung, colorectal, and prostate cancers, and melanoma. Overall, compared to 2019, we found a 5.98% decrease in stage I diagnoses and a 4.55% decrease in stage IV diagnoses in 2021 (Table). Lower odds of diagnosis at stage I were most prominent among individuals who were male, aged 18-44, Hispanic, from Mid-Atlantic region, and for the cancers of melanoma, non-Hodgkin lymphoma, prostate, esophagus, and cervical cancer. Higher odds of diagnosis at stage IV in 2021 vs. 2019 were most prominent among individuals who were Hispanic, diagnosed with cancers of prostate, thyroid, liver, esophagus and cervix. Conclusions: Decreases in cancer diagnoses and proportion of early-stage diagnoses continued in 2021 in the US. The proportion of late-stage diagnoses were lower in 2021 than 2020 but have not returned to pre-pandemic levels. Changes in stage I distribution among major cancer sites 2021 vs. 2019. 2019 2021 2021 vs. 2019 Cases Cases Percent Change AdjustedOR* (95%CI) All Cancers 341971 321514 -5.98% 0.978 (0.972-0.985) Female breast 116828 116780 -0.04% 1.023 (1.007-1.038) Prostate 26323 21012 -20.18% 0.826 (0.809-0.843) Lung cancer and bronchus 28258 25966 -8.11% 1.033 (1.012-1.053) Colon and rectum 14258 12992 -8.88% 0.942 (0.918-0.968) Melanoma 21005 19542 -6.97% 0.936 (0.907-0.966) Data source: National Cancer Database 2019-2021. *Stage I vs. II-IV, models adjusted for age group, sex, race/ethnicity, zip-code level social deprivation index, comorbidity score, state-level COVID-19 age adjusted mortality rate, MSA, state, insurance status.