The utility and limitations of contrast-enhanced transrectal ultrasound scanning for the detection of prostate cancer in different area of prostate.

OBJECTIVE: To evaluate the ability of contrast-enhanced transrectal ultrasound (CETRUS) scanning for prostate cancer detection in different area, compared with conventional transrectal ultrasound (TRUS). METHODS: 228 patients underwent TRUS-guided prostate biopsy after examinations of TRUS and CETRUS scanning. Cancer detection between CETRUS and TRUS were compared by patient and by site in different areas (right, left; base, mid-gland, apex). The receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic performance of CETRUS. RESULTS: 89 patients were malignant and 48 patients were significant cancer. Compared with TRUS, CETRUS could increase the detection rates of overall and significant cancer (P = 0.008; P = 0.031). CETRUS had higher sensitivity, specificity (except right lobe), accuracy, positive predictive value (PPV) and negative predictive value (NPV) in total, right and left lobe (P < 0.05). The sensitivity were greater for CETRUS in all areas except left base and right apex (P < 0.05). The accuracy were greater for CETRUS in all areas except left mid-gland and right apex (P < 0.05). ROC analysis showed CETRUS totally got the AUC of 0.816. The AUC was higher in left lobe than right lobe (0.837 vs. 0.793). It was most accurate at the base (0.833), then mid-gland (0.826), and lowest in apex (0.772). CONCLUSIONS: CETRUS had a significant advantage over conventional TRUS for prostate cancer detection in different areas. CETRUS much more easily missed the cancer in apex, we must focus more on apex and may add other imaging modalities to improve the visualization and detection of prostate cancer.