Enzalutamide in Biochemically Recurrent Prostate Cancer

To the Editor: In the EMBARK trial, Freedland et al. (Oct. 19 issue)(1) provide evidence for the efficacy of androgen-receptor blockade by enzalutamide without concomitant medical castration in the treatment of biochemically recurrent prostate cancer. If this result could be shown to be generalizable to other stages of prostate cancer, it would eliminate the use of injectable drugs (which are widely used and expensive) to achieve medical castration. Effective hormonal therapy for prostate cancer could be achieved with oral agents alone, a major advance in the field. However, it would be helpful to know the effects of single-agent enzalutamide on . . .