Stage at Diagnosis for Common Cancers according to Rurality, Area Deprivation, and Insurance, 2017 to 2021

Poor access to care among rural and vulnerable populations may result in later-stage cancer diagnoses. Using Maine Cancer Registry data (2017-2021), we examined relationships between rurality, insurance, area deprivation index, and stage for breast, colorectal, lung/bronchus, and prostate cancers. Among 21,208 cancers, regional/distant spread at diagnosis was present among 24% of breast, 60% of colorectal, 69% of lung/bronchus, and 25% of prostate cancers. In the multivariable model, we modeled the odds of being diagnosed with regional/distant (vs. in situ/local spread) according to insurance, rurality, and area deprivation index. Compared with commercial insurance, we observed higher odds of diagnosis at the regional/distant stage (vs. in situ/localized) associated with having Medicaid insurance for breast [adjusted OR (AOR), 1.65; 95% confidence interval (CI), 1.33-2.04], colorectal (AOR, 1.46; 95% CI, 1.09-1.98), and prostate (AOR, 1.88; 95% CI, 1.30-2.70) cancers but no association for lung cancer. People living in isolated rural areas had higher odds of being diagnosed with later-stage colorectal (AOR, 1.24; 95% CI, 1.01-1.53), lung/bronchus (AOR, 1.22; 95% CI, 1.04-1.43), and prostate cancers (AOR, 1.24; 95% CI, 1.04-1.47) compared with urban dwellers. Living in isolated rural areas or being insured by Medicaid was associated with later-stage cancer diagnoses compared with those in more urban areas and with commercial insurance. This suggests an opportunity to improve early detection among these vulnerable populations.

Rural areas and populations with lower socioeconomic status have an increased incidence of cancer. Screening is an important tool for cancer control, and in the case of colorectal cancer polyp removal and treatment of in situ breast cancers, may be considered prevention. Early detection prevents poor cancer outcomes across these malignancies.