Socioeconomic and Demographic Factors in Genetic Testing Utilization Among Advanced Prostate Cancer Patients: A Retrospective Single-Institution Study

Introduction Germline genetic testing in patients with advanced prostate cancer (PCa) is underutilized. Socioeconomic and demographic factors are hypothesized to affect low rates of testing, but causality has not been established. This single institution, retrospective study aimed to understand what barriers may affect germline genetic testing for PCa patients. Methods The Henry Ford Health (HFH) tumor registry was queried for new diagnoses of stage 3, 4A and 4B PCa from 2017-2022. Census tract levels were assigned using patient addresses and neighborhood-based geocoding was completed for Median household income (gMHI) and Social vulnerability index (SVI). gMHI and SVI were divided into tertiles. Outcomes were referral for genetic counseling and completion of genetic testing. Univariable and multivariable logistic regression analyses were performed. Results Multivariable analysis identified a decrease in testing by 3% for each 1-year increase in age (OR=0.97, 95% CI [0.95,0.99]; p=.0052). Middle gMHI tertile patients had 52% lower OR for referral than lowest gMHI tertile patients (OR=0.48, 95% CI [0.30, 0.78]; p=0.0027). For completion of testing, the odds were 2.84 times higher for those with substage 4B than 4A (OR=2.84, 95% CI [1.70, 4.74]; p<.0001). No significant association was shown between gMHI and completion of testing. Conclusion Although socioeconomic factors have been hypothesized barriers to genetic testing, we found no evidence of such an association in our patient population. Instead, lowest gMHI tertile patients were equally likely to complete genetic testing as highest gMHI tertile patients, indicating that if such barriers exist, they can be overcome.