Background: The population of homeless individuals is at high risk of death from various causes due to lifestyle and behaviors. We and others have previously shown that cancer is a leading cause of death among homeless individuals in metropolitan Detroit, Philadelphia, and Boston. However, the burden of cancer among homeless adults has not been investigated in the Mountain West region of the United States. We assessed the epidemiology of cancer among adults who were homeless at cancer diagnosis in the state of Utah.

Patients and Methods: Using data from the Utah Cancer Registry, a population-based cancer registry and founding member of the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program, homeless adults (aged 20+ years) were identified through Utah address at cancer diagnosis listed as a homeless shelter, hospital, city park, or supplemental field indicating homelessness between 1973 and 2015. Clinicopathologic, demographic, and geographic characteristics were examined. Age-adjusted, sex-specific proportional incidence ratios (PIRs) compared site-specific cancer incidence in homeless adults to cancer incidence in the entire adult Utah (referent) population. Examination of disparities in overall survival among homeless persons compared to a propensity-score matched referent group, and by Utah geographical regions (rural vs urban areas), is currently under way.

Results: 241 individuals were identified as homeless at first primary cancer diagnosis. Homeless individuals were diagnosed with cancer in 14 Utah counties state-wide, with over one-third (34.9%) of cases diagnosed outside of the largest urban county, Salt Lake County. Based on death certificate information, 61.0% of deaths among homeless adults with cancer were coded as disease specific. Homeless men showed an excess of 158% in incidence of respiratory system cancers compared to men in the referent population with cancer (PIR 2.58, 95% CI 1.93-3.45). Proportionally, an excess of 300% in melanoma incidence (PIR 4.00, 95% CI 2.95-5.42) was noted among homeless women compared to the referent female population diagnosed with cancer.

Conclusions: Our study is the first to conduct a statewide investigation to define the presentation of cancer and patterns of cancer incidence among homeless adults in Utah. The statistically significant increase in proportional incidence of cancers of the respiratory system among homeless men may be partially attributed to the culture of tobacco use and increased smoking uptake around homeless shelters. A higher proportion of melanoma among homeless women compared to the referent female population may be partly accounted for by known skin cancer risk factors, including excess sun exposure and high elevation. The leading cause of death among homeless cancer patients in Utah was reported as disease related. Together, these insights emphasize the importance of establishing prevention and intervention strategies to improve the health of homeless persons.

Citation Format: Andreana N. Holowatyj, Lisa M. Pappas, Kimberly Herget, Macy Barrios, Caroline Himbert, Marjorie Carter, Jennifer A. Doherty, Carol Sweeney, Cornelia M. Ulrich. The burden of cancer among homeless adults in the Mountain West: A Utah statewide population-based study [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C079.