The incidence of prostate cancer in a screening population with a serum prostate specific antigen between 2.5 and 4.0 ng/ml: relation to biopsy strategy.
OBJECTIVE
It has recently been suggested that the diagnostic threshold for the prostate specific antigen (PSA) assay be lowered to enhance prostate cancer detection. A 22% incidence of prostate cancer has been reported in men with PSA between 2.5 and 4.0 ng/ml. We designed a study to confirm this observation.


METHODS
Men who participated in our free early detection program and who had serum PSA between 2.5 and 4.0 ng/ml were asked to undergo prostate biopsy. Of 268 eligible men 151 (56%) agreed to participate in this free trial. All men underwent biopsy using an 11-core multisite directed biopsy scheme. All biopsy cores were color coded for location specificity and examined by 1 pathologist.


RESULTS
Cancer was identified in 24.5% (37 of 151) of the men biopsied. The median age of men with cancer was 62 years (range 43 to 74). Conventional systematic sextant biopsies, which accounted for 6 of the 11 cores, detected 73.0% (27 of 37) of the cancers and the alternate site biopsies identified the remaining 10. Gleason score was 6 in 25 men, 3 + 4 in 5, 4 + 3 in 4 and 8 or greater in 3 (median Gleason score 6). There were 14 men who had 1 core positive for cancer, 9 had 2 and 14 had more than 2 (median number of positive cores 2). Of the 14 men with 1 positive core 11 had a less than 3 mm focus of cancer and 8 had only a positive alternate site biopsy. There were 11 cases of abnormal results on digital rectal examination, 5 of which were cancer, and 31 cases of abnormal results on ultrasonography, 13 of which were cancer. Median biological variability in PSA was +/-15% (range 0.4% to 440.0%).


CONCLUSIONS
We found a significant incidence of cancer (24.5%, 37 of 51) in men with serum PSA between 2.5 and 4.0 ng/ml. In our study 67.6% of the detected cancers were significant based on the biopsy data. If the PSA threshold is lowered the conventional systematic sextant technique may be preferable to an extended strategy.
Babaian
R J
RJ
Department of Urology, The University of Texas, M. D. Anderson Cancer Center, Houston, Texas, USA.
Johnston
D A
DA
Naccarato
W
W
Ayala
A
A
Bhadkamkar
V A
VA
Fritsche HA
H A
HA
D000328:Adult; D000368:Aged; D001706:Biopsy / Q000379:methods; D006801:Humans; D015994:Incidence; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000453:epidemiology*
D017430:Prostate-Specific Antigen