Abstract
IMPORTANCE: Rural patients face unique barriers in obtaining high-quality cancer care. Research is lacking in determining whether these disparities translate to negative clinical outcomes. OBJECTIVE: To determine if there are differences in the rate of biochemical recurrence in prostate cancer between rural and urban men. DESIGN, SETTING, AND PARTICIPANTS: This cohort study used patient data that was abstracted from the North Carolina Prostate Cancer Comparative Effectiveness and Survivorship Study, a population-based cohort that prospectively followed patients with newly diagnosed prostate cancer from the Rapid Case Ascertainment system of the North Carolina Central Cancer Registry from January 1, 2011, to June 30, 2013. Patients were identified who had received either surgery or radiation within 1 year of diagnosis. Data were analyzed from January 2011 to December 2022. EXPOSURE: Patients were categorized as rural or urban using the Rural-Urban Continuum Code. MAIN OUTCOME AND MEASURES: Recurrence was determined by prostate-specific antigen testing. Demographic differences between rural and urban patients were assessed using 2-sample independent t test and χ2 test. Prostate cancer recurrence was analyzed using Cox proportional hazard models. RESULTS: A total of 778 patients were included with a median (IQR) follow-up of 4.6 (2.0 to 6.9) years and a mean (SD) age of 63 (7.4) years. Additionally, 213 were Black men (27.4%), 565 were White men (72.6%), 350 were Medicare insured (45.1%), 324 had an income ranging from $40 000 to $90 000 (43.1%), 370 were a National Comprehensive Cancer Network (NCCN) intermediate risk group (47.6%), 449 were treated with radical prostatectomy (57.7%), and 690 were in good to excellent health (88.7%) with 191 living in a rural setting (24.6%). On univariable analysis, rural residence (hazard ratio [HR], 2.19 [95% CI, 1.38 to 3.46]; P < .001), NCCN risk group (HR, 4.13 [95% CI, 2.25 to 7.57]; P < .001), and having had fewer than 12 biopsies (HR, 1.70 [95% CI, 1.08 to 2.67]; P = .02) were significantly associated with biochemical recurrence. On multivariable analysis adjusted for location of residence, marital status, overall health, number of cores biopsied, NCCN risk group, and treatment type, rural residence was significantly associated with recurrence (HR, 1.74 [95% CI, 1.07 to 2.82]; P = .03), while radiation therapy was inversely associated with recurrence (HR, 0.51 [95% CI, 0.31 to 0.85]; P = .01). CONCLUSIONS AND RELEVANCE: In this cohort study of patients with newly diagnosed prostate cancer, rural patients with prostate cancer had higher rates of biochemical recurrence. The etiology of this disparity is unclear but is likely multifactorial. Factors that may play a role include socioeconomic status, delay and disruptions in care, and access to multidisciplinary cancer care.