Contrast-enhanced transrectal ultrasonography for detection and localization of prostate index tumor: correlation with radical prostatectomy findings.

ABSTRACT

OBJECTIVE: To evaluate the ability of contrast-enhanced transrectal ultrasonography (CETRUS) to detect and localize prostate index tumor. METHODS: Eighty-three patients with biopsy-proven prostate cancer (PCa), who were scheduled to undergo radical prostatectomy, were enrolled in this prospective study. Each patient underwent baseline grayscale and CETRUS imaging of the prostate according to a standardized protocol before the operation. Ultrasonography findings (CETRUS and grayscale imaging) were correlated with step-section histopathology. RESULTS: Overall, 53 and 68 tumor foci were detected by grayscale imaging and CETRUS, respectively. The combination of grayscale imaging and CETRUS allowed identification of 89 of the 232 cancer foci (38.4%). The sensitivity of combined imaging was significantly superior to that of grayscale imaging (P<.01) and CETRUS (P<.05). Additionally, the prostate index tumor detection rate by the use of grayscale imaging, CETRUS, and their combination was 42 of 83 (50.6%), 53 of 83 (63.9%), and 67 of 83 (80.7%), respectively. The combined approach performed significantly better than grayscale and CETRUS imaging (P<.001 and P<.05, respectively). The index tumor detection rate of CETRUS was higher than that of grayscale imaging, but no significant difference was found (P>.05). CONCLUSION: Our study has demonstrated significantly improved detection of both PCa and index tumor with a combined approach of CETRUS and grayscale imaging compared with baseline grayscale technique only, and this technique may be applicable to focal therapy of PCa.