Trends of Care and Survival Outcomes for Young Men with Localized High-Risk Prostate Cancer: A National Cancer Database Analysis

Abstract

Controversy exists on the optimal management of high-risk prostate cancer, especially among those with extended life expectancies at time of diagnosis. Treatment typically involves radical prostatectomy (RP) or radiation therapy with extended course androgen deprivation therapy (RT+ADT). The purpose of this study was to examine trends in management for high-risk prostate cancer in patients <55 years old and to determine if these treatment strategies lead to equivalent overall survival (OS) in this population. From 2004-2013, 77,322 patients with localized high-risk prostate cancer treated by RP or RT+ADT were identified using the NCDB. Final analysis included 8,618 patients who were <55 years old at diagnosis. Trends in use of RP vs. RT+ADT were assessed over this period. Characteristics analyzed in this population include age, race, insurance type, median income, Charlson-Deyo score (CDS), year of diagnosis, type of treatment facility, and treatment type. The primary outcome was OS. 5-year survival rates were estimated using the Kaplan-Meier method. Adjusted hazard ratios (HR) with 95% confidence intervals (CI) were computed using multivariate (MVA) Cox regression and propensity score-matched (PSM) analysis was also performed. A total of 6,981 (81.0%) patients received RP while 1,637 (19.0%) received RT+ADT as primary treatment. Median (interquartile range) age was 51 years (49-53 years) with median follow up of 53.2 months (32-81 months) and median RT dose was 75.6 Gy in 40 fractions. Between 2004 and 2013, relative use of RP increased from 77.1% to 83.9%, while relative use of RT+ADT decreased from 22.9% to 16.1% (p<0.001). 5-year OS was estimated to be 96.0% for RP and 88.2% for RT+ADT (p<0.001). On MVA, treatment with RT+ADT was associated with significantly worse OS compared to treatment with RP (HR=2.36, 95% CI 1.96-2.85, p<0.001). Survival benefit of RP was confirmed on PSM analysis, with 5-year OS estimates of 94.5% for RP and 88.2% for RT+ADT (p<0.001). On MVA for patients receiving either treatment, black men had improved OS compared to white men (p=0.018), Medicare and Medicaid patients had worse OS compared to those with private insurance (p<0.001), and patients with CDS ≥ 2 had worse OS compared to patients with CDS of 0 (p=0.001). The use of RP as primary treatment for localized high-risk prostate cancer in patients <55 years old increased between 2004 and 2013. RP is significantly more likely than RT+ADT to be used as initial treatment. RP was also associated with significantly improved 5-year OS when compared to RT+ADT. There is likely a component of selection bias influencing this finding, as the NCDB does not account for all confounding factors and comorbidities. More research needs to be done before reaching a conclusion, but the potential benefit from RP should be considered for high-risk patients.