Introduction: There is evidence of racial disparities in the refusal of guideline-concordant treatment for localized prostate cancer. However, little is known about racial disparities in treatment refusal among men with metastatic prostate cancer. Therefore, we sought to examine whether Black-White disparities exist in patient refusal of various systematic therapies for metastatic prostate cancer. Methods: We retrospectively queried the National Cancer Database for men with a clinical diagnosis of metastatic prostate cancer between 2004 – 2020 who were offered first-line systemic therapy using at least one of the following: hormone therapy, chemotherapy, or immunotherapy. Refusal of first-line therapy was recorded if systemic treatment was refused by the patient, the patient’s family member, or their guardian. We compared baseline sociodemographic, and clinical data, and rates of refusal of systemic therapies between Black and White men. Then, for each systemic therapy type, we fitted a multivariable logistic regression to evaluate whether there are Black-White disparities in treatment refusal adjusting for age, insurance coverage, Charlson comorbidity index, census tract median income quartiles, the burden of metastasis at diagnosis, facility type and location where care was sought, and the year of diagnosis. Results: The cohort included 102,411 men with metastatic prostate cancer of which 21,444 (20.9%) men were Black. Black men were more likely to have a lower income, be uninsured, and have a higher burden of metastasis at diagnosis (p < 0.001). After adjusting for covariates, NHB were more likely to refuse chemotherapy (aOR 2.18; 95%CI 1.54-3.09; p<0.001) compared to NHW. However, there were no racial disparities in the refusal of hormone therapy (aOR 1.16; 95%CI 0.94-1.43; p=0.16) or immunotherapy (aOR 1.10; 95%CI 0.59-2.07; p=0.76) as a first-line treatment for metastatic prostate cancer. Conclusions: Among men with metastatic prostate cancer, there are racial disparities in refusal of chemotherapy, but not for hormone therapy or immunotherapy. Cultural differences and economic disparities may play a role in accepting chemotherapy treatment. Further research is needed to elucidate the factors that may be driving this difference and how to address them. SOURCE OF Funding: None
