The value of contrast-enhanced transrectal ultrasonography in detection index tumor of prostate cancer and estimation of the tumor size

Abstract

Objective To determine the value of contrast-enhanced transrectal ultrasonography (CETRUS) in detection index tumor of prostate cancer and estimation of the tumor size. Methods From July 2013 to May 2016, a total of 83 patients with biopsy-proven prostate cancer who were scheduled to undergo radical prostatectomy were recruited for this study. Each patient was evaluated with ultrasonography at baseline and CETRUS examination prior to biopsy. Patient age ranged from 45 to 75 years, with a mean of 66 years. The mean PSA of the patients was 10.9 ng/ml with a range of 4.2-21.8 ng/ml. The findings of baseline grayscale ultrasonography and CETRUS was finally correlated with step-section histopathology. Results For prostate cancer, the detection rate of baseline grayscale imaging, CETRUS and combination of two examinations was 63.9%(53/83), 79.5%(66/83)and 86.8%(72/83), respectively. For index tumor, the detection rate of corresponding method was 50.6%(42/83), 63.9%(53/83) and 74.7%(62/83), respectively. The detection rate of prostate cancer with baseline grayscale imaging was significantly lower than that with CETRUS and combination of two examinations (P 0.05 and 11.9mm vs. 10.9 mm, P>0.05). The mean maximum diameters for CETRUS and histopathology examinations were significantly different between index tumors and non-index tumors (P 15mm for index tumors was significantly higher than for non-index tumors ( χ2=3.901, P<0.05). Conclusion CETRUS improves index tumor detection of prostate cancer and is an accurate imaging technique for measuring index tumor size, especially for tumors with diameter > 15 mm. Key words: Prostate cancer; Contrast-enhanced ultrasonography; Index tumor; Radical prostatectomy