Changes in cancer diagnoses and stage distribution during the COVID-19 pandemic in the United States, 2019-2022.

Underdiagnoses and decreases in early-stage diagnoses occurred during 2020 in the United States, the first year of the COVID-19 pandemic, particularly in medically underserved populations. This study examined changes in cancer diagnoses and stage distribution in 2021 and 2022 among adults using newly released nationwide cancer registry data. Adults aged ≥18 years newly diagnosed with first primary malignant cancers between January 2019 and December 2022 from 50 US states and the District of Columbia were identified from the National Cancer Database. We calculated monthly diagnoses, stage distribution, and adjusted odds ratios of the percentage of stage I cancer diagnoses in 2020, 2021, and 2022 compared with 2019, controlling for sociodemographic and clinical factors and stratified by cancer type. A total of 3,342,235 individuals newly diagnosed with cancer were included in the study, of whom 863,793 were diagnosed in 2019, 787,366 in 2020, 872,638 in 2021, and 818,438 in 2022. The percentage of stage I diagnosis in 2021 (39.0%) and 2022 (39.2%) was higher than in 2020 (38.2%), but still lower than in 2019 (39.6%). Patterns of stage I diagnoses varied by cancer type. This cross-sectional study found that overall cancer diagnoses and the percentage of stage I diagnoses increased in 2021 and 2022, but have not returned to the pre-pandemic levels, with exceptions for some cancer types. Ongoing monitoring is warranted to address the long-term impact of the COVID-19 pandemic on cancer diagnosis and outcomes in the United States.