Urinary PCA3 Adds to Predictive Models in Patients Presenting for Initial and Repeat Biopsy for Detection of Prostate Cancer
In a study reported in the Journal of Clinical Oncology, Wei et al found that use of urinary prostate cancer antigen 3 (PCA3) measurement could improve avoidance of repeat prostate biopsy and detection of prostate cancer in biopsy-naive patients.
This National Cancer Institute study involved 859 men (mean age, 62 years) from 11 centers scheduled for diagnostic prostate biopsy between December 2009 and June 2011.
Positive and Negative Predictive Values
PCA3 scores were reported as a ratio of urinary PCA3 mRNA to prostate-specific antigen mRNA. Among men presenting for initial prostate biopsy, PCA score > 60 had a sensitivity of 42%, specificity of 91%, and positive predictive value of 80% (95% confidence interval [CI] = 72%–86%) for detection of any cancer. Among men presenting for repeat biopsy, PCA score < 20 had negative predictive value of 88% (95% CI = 81%–93%), with sensitivity and specificity of 76% and 52% for absence of cancer.
Addition of PCA3 to Risk Model
In receiver operating characteristic area under the curve (AUC) analysis, the addition of PCA3 to the Prostate Cancer Prevention Trial risk calculator (including age, race, prostate-specific antigen, digital rectal exam abnormalities, prior negative biopsy, and family history of prostate cancer) increased AUC from 0.68 to 0.79 (P < .001) for initial biopsy detection of any cancer, from 0.64 to 0.69 (P < .003) for repeat biopsy detection of any cancer, from 0.74 to 0.78 (P < .001) for initial biopsy detection of high-grade cancer, and from 0.74 to 0.79 (P = .003) for repeat biopsy detection of high-grade cancer.
The investigators concluded: “These data independently support the role of PCA3 in reducing the burden of prostate biopsies among men undergoing a repeat prostate biopsy. For biopsy-naive patients, a high PCA3 score (>60) significantly increases the probability that an initial prostate biopsy will identify cancer.”
John T. Wei, MD, University of Michigan, Ann Arbor, is the corresponding author for the Journal of Clinical Oncology article.
The study was supported grants from the National Cancer Institute. For full disclosures of the study authors, visit jco.ascopubs.org.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
