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Prostatic calculi do not influence the level of serum prostate specific antigen in men without clinically detectable prostate cancer or prostatitis.

PURPOSE
Prostatic calculi are common but little is known of their effect on serum prostate specific antigen (PSA). We investigated whether prostatic calculi might influence serum PSA in men with clinically undetectable prostatic cancer or prostatitis.


MATERIALS AND METHODS
Between November 1999 and November 2001, 581 consecutive patients underwent serum PSA determination and digital rectal examination. Of these patients 486 without detectable prostatic cancer, or a history or symptoms of prostatitis and with other specified exclusion criteria were included in the study. The detection and volume measurement of prostatic calculi, and the measurement of prostate volume were performed by transrectal ultrasonography.


RESULTS
Prostatic calculi were detected in 198 of the 486 men (40.7%). Mean patient age, prostate volume and serum PSA were not significantly different in men with and without prostatic calculi. Prostate volume was significantly greater in patients with abnormally elevated serum PSA than in those with normal levels. However, no significant difference was found between the percent of men with prostatic calculi or the volumes of prostatic calculi in the 2 groups. Univariate logistic regression analysis indicated that the presence or volume of prostatic calculi was not a risk factor for elevated PSA. Multivariate analysis showed that age and prostate volume were associated with elevated PSA.


CONCLUSIONS
The presence or volume of prostatic calculi had no significant effect on serum PSA. Our results suggest that the influence of prostatic calculi is irrelevant in men with elevated PSA.