Rates and predictors of cancer screening in California (CA) prisons.

1607 Background: Cancer is the leading cause of death in state prisons. Patients diagnosed with cancer in prison are more likely to have Stage IV diagnoses and have worse survival. Rates and predictors of cancer screening in prison and the relationship to stage at diagnosis are unknown. Methods: This retrospective study evaluated patients incarcerated in CA prisons in 2014-2023 who met screening criteria for breast, cervical, colon, liver and lung cancers during periods tracked by the prison system (Table). Correctional data were used to identify screening-eligible patients incarcerated during the study period, screening eligibility dates, receipt of screening and periods of incarceration. These data were matched to CA cancer registry data from 2014-2021 using name and date of birth; cancers were identified between the start of the tracking period for each cancer and 2021. For each cancer, we calculated the proportion of: patients who ever received cancer screening, time covered by a screening test (sum of non-overlapping time of screening intervals [e.g., 10 years for colonoscopy] divided by time eligible for screening), and patients diagnosed at Stage IV (stratified by ever-receipt of screening prior to diagnosis). Generalized estimating equations models with logit link adjusted for demographic and incarceration characteristics (e.g. incarcerated in the past year) clustered at the prison+yard level were used to determine predictors of receipt of screening for each cancer and the association of ever-receipt of screening with Stage IV diagnosis. Results: The study included 83,174 individuals who were 79% male, had a median age of 51 when first eligible for any screening, and were 33% Non-Hispanic White. Rates of ever receiving cancer screening ranged from 43-87%, and mean proportion of time covered ranged from 30-75% (Table). In adjusted models, receipt of outpatient mental health services, higher security level and recent change in prison or primary care clinician were associated with higher screening rates for most cancers. 597 screenable cancers were diagnosed from the start of each screening tracking period through 2021. 17% of cancers were diagnosed as Stage IV. In the adjusted model including all cancers, patients who ever received screening prior to diagnosis were 60% less likely to be diagnosed with Stage IV disease (OR 0.40, 95% CI 0.24-0.69). Conclusions: Cancer screening rates in CA prisons are high and may explain why rates of Stage IV diagnoses in CA prisons are comparable to the general population and lower than in other state prisons. Breast Cervical Colon Liver Lung Start of tracking period (all end 6/2023) 1/2014 1/2016 1/2014 10/2015 7/2022 N 3,218 16,238 68,086 5,644 3,406 Ever screened, n (%) 2,408 (75) 11,326 (70) 49,023 (72) 4,935 (87) 1,479 (43) Mean proportion of time covered 72% 74% 62% 75% 30% Cancer diagnosed, n 58 12 280 247 - Stage IV at diagnosis, screened, % 5% 0% 21% 12% - Stage IV at diagnosis, not screened, % 7% 0% 35% 21% -