The incidence of prostate cancer in men with prostate specific antigen greater than 4.0 ng/ml: A randomized study of 6 versus 12 core transperineal prostate biopsy

Purpose: The prostate cancer detection rate in patients with elevated prostate specific antigen (PSA) increases with extended needle biopsy protocols. Transperineal biopsy under transrectal ultrasound guidance is rarely reported, although notable cancer diagnoses are obtained with this technique. We describe the results of 6 and 12 core transperineal biopsy. Materials and Methods: A total of 214 patients with PSA greater than 4.0 ng/ml were prospectively randomized to undergo 6 or 12 core transperineal biopsy. Each group of 107 patients was comparable in terms of clinical characteristics. The procedure was performed on an outpatient basis using local anesthesia. Specimens were obtained with a fan technique with 2 puncture sites slightly above the rectum (1 per lobe) under transrectal ultrasound guidance. Cores were taken from all peripheral areas, including the far lateral aspect of the prostate. Results: The overall cancer detection rate was 38% and 51% for 6 and 12 core biopsy, respectively. In patients with PSA between 4.1 and 10 ng/ml the cancer detection rate was 30% and 49% for 6 and 12 core biopsy, respectively. Conclusions: The 12 core transperineal prostate biopsy is superior to 6 core biopsy. The technique provides optimal prostate cancer diagnosis. About half of the patients with PSA greater than 4.0 ng/ml and a slightly lower percent with PSA between 4.1 and 10 ng/ml have prostate cancer.