Biochemical Recurrence of Prostate Cancer About The prostate is a walnut-sized gland that is a part of the male reproductive system. It secretes a fluid that nourishes and protects the sperms, which are the male reproductive cells. Cancer of the prostate is a major cause of concern in aging men. Prostate cancer usually resolves after primary therapy in the majority of men. However, in some men, a condition called biochemical recurrence (BCR) occurs, also known as biochemical relapse or PSA failure. In this condition, the prostate-specific antigen (PSA), a protein produced by the normal and prostate cancer cells starts to become elevated and detectable by the PSA test. There are different cut-offs for the PSA level, depending on the treatment modality, such as surgery or radiotherapy.