Use of transrectal ultrasound and prostate-specific antigen in diagnosis of prostatic intraepithelial neoplasia.

1. PIN can present as a hypoechoic lesion on ultrasound. 2. Biopsy results prove a close relationship between PIN and cancer. 3. Measurements of age, lesion size, and PSA for diagnoses of PIN were intermediate values between non-cancer and cancer. 4. Sequential, precise transrectal ultrasound-guided biopsies of hypoechoic lesions are now possible, and close follow-up of patients with diagnoses of PIN is therefore possible.