S. Viswanath et al., ROUTINE ESTIMATION OF PROSTATE-SPECIFIC ANTIGEN PRIOR TO CLINIC ATTENDANCE IN PATIENTS WITH SYMPTOMS OF BLADDER OUTLET OBSTRUCTION, British Journal of Urology, 72(2), 1993, pp. 187-189
We report the use of serum prostate specific antigen (PSA) estimations
prior to clinic attendance in 234 patients referred with symptoms of
bladder outlet obstruction to a general urology clinic. Ninety-three p
atients with PSA levels > 10 ng/ml were seen earlier than planned and
offered transurethral resection or transrectal biopsy of the prostate
gland. Forty-six patients (49%) proved to have carcinoma of the prosta
te, compared with 10 of 141 (7%) patients who had PSA values < 10 ng/m
l. With a decision value of 10 ng/ml, the sensitivity for detecting ca
rcinoma was 82% and specificity 73.5%. Using a decision value of 7 ng/
ml improved the sensitivity to 95% without significantly affecting the
specificity (70%). Twenty-four patients with prostatic cancer had bon
e metastases; the sensitivity of PSA for predicting a positive bone sc
an using a decision value of 25 ng/ml was 92%, but the specificity was
only 31%.