Survival Outcomes for Rural Patients With Advanced Prostate Cancer: A SEER Investigation.

Abstract

Background: Differences may exist in survival for patients with de novo metastatic prostate cancer according to urban-rural status.

Methods: This cohort study utilized the Surveillance, Epidemiology, and End Results database. Data on demographics, urban-rural status, histopathology, and survival were extracted for men aged ≤ 75 years, diagnosed with metastatic prostate cancer between 2009 and 2018. Patients missing rurality status or survival outcome-related data were excluded. Differences between urban and rural cohorts in overall and cancer-specific survival were analyzed using Cox regression and restricted mean survival time. Subgroup analyses were performed for variant histological subtypes of prostate cancer. Sensitivity analyses were performed for varying definitions of rurality.

Results: Altogether, 21,290 participants were included. The cohorts of rural and urban participants differed in age, race, US region, and marital status. Cox regression failed to demonstrate associations between urban-rural status and overall survival (adjusted hazard ratio = 1.03, 95% confidence interval: 0.97-1.09) and cancer-specific survival (1.03, 0.97-1.10). Restricted mean survival time modeling demonstrated that urban patients lived 2.29 months longer than rural patients (95% confidence interval: 0.61-3.97). Sub-analyses of neuroendocrine, intraductal, and other histological subtypes, did not demonstrate any association between urban-rural status and overall survival. A more selective definition of rurality resulted in a persisting difference in overall survival (2.12 months, 0.24-4.01) through restricted mean survival time. Similarly, a broader definition of rurality also resulted in a difference in overall survival (1.98 months, 0.59-3.36).

Conclusion: This study demonstrated that US individuals with metastatic prostate cancer residing rurally may have slightly poorer survival compared to patients from urban areas.