Racial, Socioeconomic, and Geographic Disparities in the Receipt, Timing to Initiation, and Duration of Adjuvant Androgen Deprivation Therapy in Men with Prostate Cancer.

OBJECTIVE: This retrospective cohort study aims to examine the receipt, timing to initiation, and duration of androgen deprivation therapy (ADT) in men with prostate cancer by race/ethnicity, socioeconomic status, and geographic location.

METHODS: The study population are patients from Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database, who were 66 years or older and newly diagnosed with stage III and IV prostate cancer in 1992-2009 and underwent radiation therapy, where ADT was proven to be highly beneficial and its use was considered as most appropriate (n = 12,170). We use logistic regression to examine the receipt of ADT and linear regression to study factors associated with time to ADT initiation while controlling for baseline characteristics.

RESULTS: Overall, 77% of eligible patients received at least one form of ADT in combination with radiation therapy, of which 12% underwent orchiectomy and the rest received ADT, and 77.2% of non-Hispanic white and 80.7% of Hispanic patients received ADT compared to 73.8% of non-Hispanic black. After adjustment for demographic and tumor characteristics, black men and men of other races are less likely to receive ADT compared to white counterparts (OR = 0.64 and 0.74, respectively). The median time from cancer diagnosis to ADT initiation is 2 months. Once initiated, men received a median of seven drug injections. After controlling for covariates, race/ethnicity and geographic location (SEER areas) are associated with early initiation of therapy. White, Hispanic men and men living in the South initiate ADT earlier.

CONCLUSION: Significant racial disparities exist in the receipt and use of this highly beneficial therapy, and there are geographic variations in the utilization of this therapy.