Characterizing prostatic adenocarcinomas in men with a serum prostate specific antigen level of < 4.0 ng/mL.
OBJECTIVE
To characterize prostate cancer in men undergoing radical prostatectomy who have a prostate-specific antigen (PSA) level of < 4.0 ng/mL, hypothesizing that a low PSA is not caused by diminished tumour production of PSA, nor does it signify clinically insignificant disease.


METHODS
Seventy-nine men (mean age 59.3 years, range 43-77) with a PSA level of < 4.0 ng/mL were identified from 702 who had a radical prostatectomy between 1994 and 2000. Demographic and clinical data were analysed; pathological specimens were evaluated by routine haematoxylin and eosin staining and immunohistochemistry with anti-PSA antibody, for both pathological staging and grading, and for the presence of PSA production. Tumours were classified as 'clinically insignificant' if the tumour volume was < 0.5 mL and the Gleason score < 7.


RESULTS
The mean (SD, range) preoperative PSA level was 3.04 (0.85, 0.8-3.8) ng/mL Indications for biopsy included an abnormal digital rectal examination (61%), a PSA velocity of > 0.75 ng/mL/year (12%), a strong family history of prostate cancer (3%), obstructive urinary symptoms (2%), or no obvious indication (23%). Thirty-eight (48%) tumours were clinically insignificant. Of 41 clinically significant cancers, 13 had a final Gleason score of > or = 7, 20 had extraprostatic extension and 11 had a tumour volume of > or = 10 mL Of the 79 prostate cancer specimens 78 stained strongly for PSA; the exception was a Gleason 9 tumour. With a mean (range) follow-up of 3.5 (0.18-6) years only one patient had a biochemical recurrence (PSA > or = 0.1 ng/mL).


CONCLUSIONS
Most prostate cancers in men with a PSA level of < 4.0 ng/mL are clinically significant and PSA-producing. Many of these tumours are high-grade, high-volume and extraprostatic. We are currently exploring factors to explain why serum PSA is not elevated in these men, including tumour location, pattern of invasion and microvessel density.
Sokoloff
M H
MH
Department of Surgery, Section of Urology, University of Chicago, Chicago, Illinois, USA. msokolof@surgery.bsd.uchicago.edu
Yang
X J
XJ
Fumo
M
M
Mhoon
D
D
Brendler
C B
CB
D000230:Adenocarcinoma / Q000097:blood* / Q000473:pathology; D000328:Adult; D000368:Aged; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology
D017430:Prostate-Specific Antigen