To determine if genetic variants in drug or hormone metabolizing enzymes and transporters are related to prostate cancer outcomes, we are currently evaluating ~235 genotypes included on the Drug Metabolizing Enzymes and Transporters Array (Affymetrix) in approximately 200 patients with prostate cancer. We included a subset of samples that had previously been reported in Hamada et al1 and determined that there were several miscalls of the CYP17 -34T>C that were most likely caused by error-prone RFLP technology used in the initial report. We therefore used direct sequencing to validate all of the findings of Hamada et al. Patient samples (n = 147) and controls (n = 40) were available for validation of genotype data, and we found that there were 30 genotype errors in patients with prostate cancer and 3 were detected in the control group (concordance rates are 80% and 93%, respectively). Overall survival differences were more statistically significant using the updated genotypes (P = .0050 vs P = .040; Fig. 1) whereas no associations were detected between genotype and risk or patient characteristics (P > .33; Tables 1 and 2). Therefore, the corrected data do not change the findings of Hamada et al, but alters the statistics slightly.