Abstract Background: Breast cancer is the most commonly diagnosed cancer worldwide and in South Korea. Although Korea provides universal health coverage, the extent to which socioeconomic status (SES) influences breast cancer care and outcomes remains unclear. This study evaluated SES-related differences in screening participation, stage at diagnosis, treatment patterns, and survival within a universal healthcare system. Methods: We analyzed 111,585 women aged ≥40 years diagnosed with breast cancer between 2014 and 2019 using the K-CURE dataset. SES was classified into five income- and insurance-based groups: Medical Benefit status and four NHI premium quartiles. Variables included screening participation, cancer stage, and treatment. Kaplan–Meier estimates compared unadjusted survival, and multivariable Cox proportional hazards models estimated adjusted hazard ratios for mortality outcomes. Results: Lower SES was associated with reduced screening participation, more advanced stage at diagnosis, and lower treatment receipt. The Medical Benefit group showed the highest proportion of distant-stage cancer (8.4%) and the highest no-treatment rate (2.7%). Mortality was substantially higher among non-screened patients across all SES groups. In multivariable analyses, low SES, advanced stage, and non-receipt of standard treatments were significant predictors of increased breast cancer-specific mortality. Despite high overall treatment rates, disparities persisted among socioeconomically disadvantaged groups. Conclusion: Significant income- and insurance-based socioeconomic disparities in breast cancer detection, treatment receipt, and survival remain even within a universal healthcare system. Targeted strategies to improve screening participation and ensure equitable access to care for vulnerable populations are essential to reduce SES-related survival gaps. Impact: Socioeconomic disparities persist despite universal health coverage.
Abstract Background: Iowa has the second-highest overall cancer incidence rate (IR) in the United States and is one of three states with increasing IRs. We aim to identify site- and stage-specific drivers of Iowa’s increasing IRs compared with seven surrounding states combined. Methods: Sex-specific trends in age-standardized IRs (overall, site-specific, and stage-specific), mortality rates (MR; 2001–2022), and screening and risk factor prevalence (1992–2022) were examined in both regions using joinpoint regression. Iowa-to-surrounding-state IR and MR ratios and prevalence ratios were calculated. Results: After earlier stable trends, Iowa’s overall cancer IR increased 0.6% annually among males (2013–2022) and females (2005–2022). From 2013 to 2022, Iowa’s largest IR increases were for prostate, melanoma, and kidney cancers among males and breast, melanoma, and uterine cancers among females, predominantly at localized stage; advanced-stage prostate and breast cancer IRs also slightly increased. Overall IRs were comparable between regions through 2013; thereafter, IRs increased in Iowa but remained stable in surrounding states. In 2022, Iowa’s overall IRs exceeded surrounding states by 11% among males and 6% among females. Prostate cancer accounted for 43.5% of male divergence, and breast and lung cancers for 57.8% among females. MRs declined in both regions. Screening and risk factor prevalence trends were generally comparable between regions, although trends in male binge drinking were less favorable in Iowa compared with those in surrounding states. Conclusions: Iowa’s increasing incidence largely coincided with increasing localized-stage IRs, particularly among detection-sensitive cancers, whereas cancer mortality declined. Impact: Increasing cancer incidence, particularly advanced-stage disease at selected sites, warrants sustained preventive intervention in Iowa.
Abstract Background: Reliable sub-state cancer screening estimates are needed to identify geographic disparities and guide interventions, but survey data often lack sufficient precision for small-area analyses. Multi-payer claims data offer a promising alternative, though constructing screening-eligible cohorts is complicated by transitions across payers over time. Methods: We used the University of North Carolina Cancer Information and Population Health Resource to develop a longitudinal multi-payer cohort of insured North Carolina residents from 2003 to 2020. Deterministic linkage based on Social Security Number (SSN), date of birth, and sex was used to identify unique individuals across private insurance, Medicare, and Medicaid. As a use case, we constructed annual colorectal cancer (CRC) screening–eligible cohorts for 2012–2020 using two definitions of 10-year enrollment. Results: The parent cohort included 12,010,374 unique individuals with 74,779,932 person-years of follow-up. Median continuous enrollment was 60 months (interquartile range, 19–122), and 24.7% linked to multiple payers over time. In 2020, the annual CRC screening cohort covered an estimated 56% of insured North Carolina residents aged 45–75 years. A flexible enrollment definition increased cohort size by approximately 10% with minimal demographic differences. Statewide up-to-date CRC screening prevalence was approximately 80% and stable across the study period, with geographic variation observed across small areas. Conclusions: This resource provides a scalable framework for constructing screening-eligible populations from multi-payer claims and generating small-area cancer screening estimates. Impact: This infrastructure has particular value for identifying screening disparities in underserved populations that are poorly captured by traditional survey methods.
Abstract Opium consumption is most prevalent in Southwestern and South Asia, particularly in regions surrounding the major opium-producing areas of the Golden Crescent. The International Agency for Research on Cancer classifies opium consumption as a group 1 human carcinogen, with sufficient evidence for lung, laryngeal, and urinary bladder cancers. Opium consumption involves complex exposure profiles, including combustion-derived exposures from opium and its fuels, as well as coexposures from tobacco smoking and indoor biomass burning. Recent molecular epidemiologic research in the prospective Golestan Cohort Study provides an opportunity to move beyond self-reported opium use by characterizing internal exposure to multiple opioid and non-opioid constituents. In a nested case–control study of 53 matched lung cancer pairs among opium users, 35 urinary metabolites reflecting exposure to opiates, volatile organic compounds, polycyclic aromatic hydrocarbons, and nicotine were measured. Higher concentrations of morphine-3-glucuronide, morphine-6-glucuronide, 2-hydroxypropyl mercapturic acid, and 2-hydroxyethyl mercapturic acid were associated with lung cancer. These findings provide an important initial demonstration of the potential of urinary biomarkers to characterize complex exposures associated with opium consumption. Future studies integrating driver mutations, mutational signatures, and tumor microenvironment characteristics may provide further insight into mechanisms of opium-related lung carcinogenesis and inform cancer prevention and precision oncology. See related article by Naghash et al., p. 1880
