CONTRAST-ENHANCED ENDORECTAL COIL MRI IN LOCAL STAGING OF PROSTATE CARCINOMA

Objective: Our goal was to evaluate contrast-enhanced MRI using an endorectal coil in detecting and staging prostate carcinoma. Materials and Methods: Sixty patients with clinically suspected prostate carcinoma were examined by T1-weighted contrast-enhanced endorectal coil MRI at 1.5 T. Results were compared with T2-weighted images in all cases and with histologic findings following radical prostatectomy in 28 patients. Results: Prostate carcinomas showed no consistent pattern of contrast enhancement. In 27 patients, the tumor enhanced less than the surrounding prostatic tissue; in 10 patients, enhancement was heterogeneous; and in 23 cases, the lesion was hyperintense compared with normal glandular tissue. With respect to tumor delineation, contrast-enhanced sequences were superior to T2-weighted images in 1 case only; in 24 patients, the tumor could not be delineated at all. However, contrast-enhanced sequences provided a higher diagnostic confidence in delineating the seminal vesicles, prostate capsule, and neurovascular bundle in nine, six, and three cases, respectively. In the operated patients, accuracy, sensitivity, and specificity for staging advanced disease were comparable for both sequences. Conclusion: The T2-weighted sequences remain mandatory for delineation of prostate carcinoma. Contrast-enhanced T1-weighted sequences do not improve overall staging accuracy and therefore are not warranted routinely, but should be considered in cases requiring clearer delineation of the prostate capsule and/or seminal vesicles.