Endoscopic ultrasonic evaluation of the prostate using a transrectal probe: prospective evaluation and acoustic characterization.

Transrectal sonography of the normal prostate demonstrates a gland that has low-level homogeneous echoes. Benign and malignant prostatic disease causes disruption of this normal texture. A prospective study was performed to determine the ability of ultrasound to detect focal defects accurately. The specific histologic diagnoses of the lesions were obtained by ultrasonically guided transperineal biopsy or prostatic resection. Acoustic characterization following pathologic evaluation demonstrated certain echogenic features to be highly suggestive of benign disease. These include hyperechoic lesions that are bright and thick, foci with shadowing, and, although uncommon, purely hypoechoic areas. Although in some instances differentiation of disease processes is difficult, this analysis suggests that in certain lesions, accurate prediction of benign and malignant disease can be made. At present, there is still enough overlap that biopsies are usually required.