Medications and surgical interventions for benign prostatic hyperplasia are potential confounders of prostate-specific antigen.

Prostate-specific antigen (PSA) is the most widely used marker for prostate cancer (CaP) screening and monitoring benign prostatic hyperplasia (BPH) progression. However, lack of an established abnormal threshold and the presence of other benign processes confound the interpretation of PSA levels. Many factors besides inflammation, trauma, and instrumentation can influence PSA levels; specifically, BPH and its associated medical and surgical therapies frequently complicate the interpretation of this serum blood test. For example, the commonly used 5 alpha reductase inhibitor (5ARI) medications directly affect PSA levels by decreasing prostate volume. The amount of time and potentially even the 5ARI formulary a patient is administered has been implicated to directly impact the degree of reduction in PSA (a proxy for prostate volume). In addition, each of the currently available surgical procedures for BPH appears to remove varying amounts of prostatic adenoma. This directly confounds CaP screening because each procedure is associated with a relatively specific postoperative nadir PSA level, and PSA kinetics are not well described in the literature. Taken together, it is important for clinicians to comprehend that BPH and its associated medical and surgical interventions should directly influence their interpretation of PSA and PSA velocity when screening for CaP or following BPH progression.