Detection rates and biologic significance of prostate cancer with PSA less than 4.0 ng/mL: observation and clinical implications from Tyrol screening project

Abstract

Objectives: To investigate the prostate cancer (PCa) detection rates and Gleason scores in patients with serum prostate-specific antigen (PSA) levels of 2.0 to 3.9 ng/mL and 4.0 to 10 ng/mL (free PSA 18% or less), in a population-based screening project. With the use of prostate-specific antigen (PSA) screening, more PCa is being diagnosed at PSA values of less than 4 ng/mL.

Methods: A total of 3446 consecutive screening volunteers with a PSA level of 2.0 to 10.0 ng/mL (free PSA 18% or less) were assessed. Ten systematic prostate biopsies and an additional five Doppler-enhanced targeted biopsies were performed on the basis of age-specific PSA reference ranges. The cumulative frequency of detection and the Gleason scores were analyzed.

Results: The PCa detection rate for patients with a PSA value of 2.0 to 3.9 ng/mL (n = 1522, group 1) and 4.0 to 10.0 ng/mL (n = 1924, group 2) was 21% (n = 320) and 30% (n = 572), respectively. Of the PCa cases detected, 37% were in men with a PSA level of 2 to 4 ng/mL. Statistically significant differences were found in age and prostate volume between groups 1 and 2, with patients in the lower PSA group younger and having a smaller mean prostate volume (P = 0.0001). Of 313 patients with PCa and a PSA value of 2 to 3.9 ng/mL, 24% had a Gleason score of 7 or greater compared with 33% of 560 patients with a PSA value of 4.0 to 10.0 ng/mL (P = 0.004).

Conclusions: Our data suggest that in a screening population, more than one third of PCa cases in men with a PSA level of 2 to 10 ng/mL will occur in those with a PSA value of 2 to 3.9 ng/mL. Also, PCa cases with a low PSA level occur in younger patients and at lower stages with a smaller prostate volume.