Risk profiles and treatment patterns among men diagnosed as having prostate cancer and a prostate-specific antigen level below 4.0 ng/ml.

Background: Despite controversy over the benefit of prostate-specific antigen (PSA) screening, little is known about risk profiles and treatment patterns in men diagnosed as having prostate cancer who have a PSA value less than or equal to 4.0 ng/mL.

Methods: We used data from the Surveillance, Epidemiology, and End Results system to describe patient characteristics and treatment patterns in the cases of 123 934 men with newly diagnosed prostate cancer from 2004 to 2006. Age-standardized treatment rates were calculated in 5-year age strata. Logistic regression was used to quantify the odds ratios (ORs) of men with low- and high-risk disease and the use of radical prostatectomy (RP) or radiation therapy (RT).

Results: Men with a PSA level of 4.0 ng/mL or lower represent 14% of incident prostate cancer cases. Fifty-four percent of men diagnosed as having prostate cancer and PSA levels lower than 4.0 ng/mL harbor low-risk disease (stage, < or =T2a, PSA level, < or =10 ng/mL, and Gleason score, < or =6), but over 75% of them received RP or RT. Men with screen-detected prostate cancer and PSA values lower than 4 ng/mL were 1.49 (95% confidence interval [CI], 1.38-1.62) and 1.39 (95% CI, 1.30-1.49) times more likely to receive RP and RT, respectively, and were less likely to have high-grade disease than men who had non-screen-detected prostate cancer (OR, 0.67; 95% CI, 0.60-0.76).

Conclusions: Most men diagnosed as having prostate cancer with a PSA threshold below 4.0 ng/mL had low-risk disease but underwent aggressive local therapy. Lowering the biopsy threshold but retaining our inability to distinguish indolent from aggressive cancers might increase the risk of overdiagnosis and overtreatment.