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Assessment of Rebound in Cancer Diagnoses in California in 2022, by Stage, Sociodemographic Factors, and Rurality
Erin L Van Blarigan1,2,3, Alison J Canchola1,2, Li Zhu4
1Greater Bay Area Cancer Registry, University of California, San Francisco, San Francisco, California.
Background:
The reduction in cancer cases in 2020 has been attributed to missed diagnoses during the pandemic, yet no rebound occurred in 2021. We examined whether cancer rebounded in California in 2022.
Methods:
Data on invasive tumors in California for 2001 to 2022 were obtained through the NCI Surveillance, Epidemiology, and End Results program. Expected cases for 2022 were calculated using joinpoint regression models based on trends from 2001 to 2021 (omitting 2020). We calculated the ratio of observed to expected (O/E) cases in 2022 and 95% confidence intervals (CI).
Results:
There was no overall difference in observed versus expected invasive tumors in California in 2022. However, lung cancer was 29% lower than expected in rural areas (O/E: 0.71; 95% CI, 0.39-0.95), uterine cancer was lower than expected in Los Angeles (O/E: 0.91; 95% CI, 0.86-0.96), and breast cancer was lower than expected in Greater California (O/E: 0.95; 95% CI, 0.90-0.98). Groups with more tumors observed than expected included unstaged colorectal cancer in Greater California (O/E: 1.54) and Los Angeles (O/E: 1.26), colorectal cancer among males (O/E: 1.12) and Asian Americans (O/E: 1.16) in the Greater Bay Area, localized melanoma in Greater California (O/E: 1.24), and prostate cancer among Hispanic males in Los Angeles (O/E: 1.24).
Conclusions:
Overall, observed invasive tumors did not differ from expected in California in 2022, but there was variation across demographic, regional, and clinical factors. The reduction in cancer cases in 2020 likely reflects multiple factors, including missed diagnoses and death due to competing causes.
Impact:
Continued close monitoring of cancer diagnoses is needed to inform cancer control strategies.
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