Prevalence and pathological extent of prostate cancer in men with prostate specific antigen levels of 2.9 to 4.0 ng./ml.

Various authors have recommended different values for the upper limit of normal for the monoclonal prostate specific antigen (PSA) assay (for example 4.0 ng./ml. or less by the manufacturer Hybritech or 2.8 ng./ml. or less by others). To our knowledge, no studies have examined the prevalence and pathological extent of prostate cancer detectable by needle biopsy in ambulatory volunteers with PSA levels in the range of 2.9 to 4.0 ng./ml. We evaluated 121 volunteers by rectal examination and transrectal ultrasonography with PSA levels in that range. We performed ultrasound-directed needle biopsy of the prostate if abnormal findings were present on either examination. The prevalence of detectable prostate cancer in this group was 7.2% (8 of 111). All 8 patients had pathologically organ confined cancer, and only 2 had suspicious findings on rectal examination but all had abnormal or suspicious ultrasound findings. We believe that the 7.2% yield from ultrasonography and biopsy in patients with a PSA level of 2.9 to 4.0 ng./ml. is too low to justify further invasive evaluation. Rather, we recommend careful followup and monitoring of these patients with serial PSA measurements and rectal examination, and advise performance of ultrasonography and biopsy if the rectal examination becomes suspicious for cancer or the PSA level increases above 4.0 ng./ml.