Shao and colleagues1 report that even with prostate-specific antigen (PSA) values below 4.0 ng/mL (to convert PSA to micrograms per liter, multiply by 1.0) there is a risk of prostate cancer, but detecting these cancers by lowering the PSA threshold might lead to overdiagnosis and overtreatment. They conclude that PSA level is not a sufficient basis for treatment decisions. In an accompanying Invited Commentary, Hoffman and Zeliadt2 agree that the health care challenge is to discover biomarkers that better identify the patients most likely to benefit from treatment.
Glaser AI. PSA: Possible Surgery Avoidance With Use of Free PSA. Arch Intern Med. 2011;171(6):594-595. doi:10.1001/archinternmed.2011.80