Abstract
PURPOSE: Germline genetic testing in patients with advanced prostate cancer (PCa) is underutilized and hypothesized to be impacted by socioeconomic and demographic factors. This single institution, retrospective study assessed the association of income and social vulnerability with genetic referrals and testing. METHODS: The Henry Ford Health (HFH) tumor registry was queried for new diagnoses of stage III, IV PCa from 2017 to 2022. 1385 patients were eligible and 186 patients (13.43%) received a referral, while 1199 (86.57%) patients did not. Median household income (gMHI) and social vulnerability index (SVI) were assigned based on census tract level geocoding and analyzed by tertiles. Univariable and multivariable logistic regression analyses were performed assessing referral for genetic counseling and completion of genetic testing as outcomes. In the multivariable analysis, associations between age, stage and gMHI were analyzed. RESULTS: Black and stage IV patients were more likely to receive genetics referral than White and stage III patients, respectively (20.3% vs 10.6%, p < 0.0001; 25.5% vs 7.3%, p < 0.0001). Multivariable analysis showed that middle gMHI tertile patients had 53% lower unadjusted OR for genetic referral than lowest gMHI tertile patients (OR = 0.47, 95% CI [0.29, 0.75]; p = 0.0017). There was no significant difference in the odds of referral between the highest and lowest gMHI tertiles (OR = 1.22, 95% CI [0.83, 1.79]; p = 0.3175). No other significant associations were found between gMHI, SVI and genetic counseling referrals or completion of testing. Adjusted comparisons showed significant associations between increased referral or testing rate and decreasing age and more advanced stage (OR = 0.97, 95% CI [0.95, 1.00]; p = 0.0218), (OR = 2.84, 95% CI [1.70, 4.74]; p = 0.0001). CONCLUSION: Although socioeconomic factors have been hypothesized as barriers to genetic testing, we found no evidence of an association in our patient population. Instead, the lowest gMHI tertile patients were equally as likely to complete genetic testing as highest gMHI tertile patients, indicating socioeconomic barriers can be overcome. Clinical factors including age and stage did independently predict completion of testing, supporting referral for testing based on clinical characteristics.