This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Sung, D. J. Articles by Moon, D. G. Search for Related Content PubMed PubMed Citation Articles by Sung, D. J. Articles by Moon, D. G.

Comparison of Prostate-Specific Antigen Adjusted for Transition Zone Volume Versus Prostate-Specific Antigen Density in Predicting Prostate Cancer by Transrectal Ultrasonography

Departments of Diagnostic Radiology (D.J.S., S.B.C., Y.H.K., Y.W.O., N.J.L., J.H.K., K.B.C.) and Urology (D.G.M.), Korea University College of Medicine, Seoul, South Korea.

Address correspondence and reprint requests to Sung Bum Cho, MD, Department of Diagnostic Radiology, Anam Hospital, Korea University College of Medicine, 126-1, 5-Ka Anam-dong, Sungbuk ku, Seoul 136-705, South Korea. E-mail:angler{at}kumc.or.kr.

Objective. Prostate-specific antigen is an excellent tumor marker, but it is not specific for prostate cancer. We evaluated the efficacy of prostate-specific antigen adjusted for transition zone volume calculated by transrectal ultrasonography in predicting prostate cancer in men with intermediate prostate-specific antigen levels of 4.1 to 10.0 ng/mL compared with prostate-specific antigen density. Methods. Between June 1998 and December 2001, prostate-specific antigen adjusted for transition zone volume was obtained from 131 patients who underwent ultrasonographically guided biopsies and had prostate-specific antigen of 4.1 to 10.0 ng/mL. Prostate-specific antigen density was calculated by dividing total serum prostate-specific antigen by total prostate volume, and total serum prostate-specific antigen was divided by transition zone volume to yield prostate-specific antigen adjusted for transition zone volume. This was compared with prostate-specific antigen density via receiver operating characteristic curves. Results. Of 131 patients, 34 (26%) had prostate cancer, and 97 (74%) had benign prostatic hyperplasia on pathologic examination. Total prostate volume was correlated with transition zone volume (P < .001). Mean prostate-specific antigen adjusted for transition zone volume and prostate-specific antigen density were 0.71 ± 0.25 and 0.27 ± 0.09 ng • mL^–1 • mL^–1 in patients with prostate cancer and 0.32 ± 0.09 and 0.16 ± 0.05 ng • mL^–1 • mL^–1 in patients with benign prostatic hyperplasia. With a cutoff value of 0.35 ng • mL^–1 • mL^–1, prostate-specific antigen adjusted for transition zone volume had sensitivity of 82% and specificity of 84%. Receiver operating characteristic curve analysis showed that prostate-specific antigen adjusted for transition zone volume predicted biopsy outcome significantly better than prostate-specific antigen density (P < .05). Conclusions. Prostate-specific antigen adjusted for transition zone volume is more accurate than prostate-specific antigen density in distinguishing prostate cancer from benign prostatic hyperplasia in men with intermediate serum prostate-specific antigen of 4.1 to 10.0 ng/mL. Determination of transition zone volume by transrectal ultrasonography may be helpful for predicting the probability of positive biopsy results.

Key Words: prostate • prostate neoplasms • ultrasonography

Abbreviations: BPH, benign prostatic hyperplasia • DRE, digital rectal examination • PSA, prostate-specific antigen • PSAD, prostate-specific antigen density • PSATZ, prostate-specific antigen adjusted for transition zone volume • ROC, receiver operating characteristic • TRUS, transrectal ultrasonography