Laparoscopic pelvic lymph node dissection with real-time interactive transrectal ultrasound guided transperineal radioactive seed implantation is a new method of treatment for localized carcinoma of the prostate. A total of 58 patients with clinically confined prostate cancer and negative seminal vesicle biopsies underwent staging laparoscopic pelvic lymph node dissection immediately followed by prostate implantation: 50 had 125iodine and 8 had 103palladium implants. Mean operating time was 226 minutes (range 120 to 475), mean blood loss was 57 cc (range 5 to 400) and average hospital stay was 2.2 days (range 0.5 to 8). At a mean followup of 12 months (range 6 to 24), complications included proctitis in 1.7% of the cases, dysuria in 24%, nocturia in 21% and outlet obstruction in 17%. Erectile function remained unchanged. Prostate volume decreased to 58.9% of the pretreatment value by 12 months and to 44.3% by 24 months. Mean prostate specific antigen level was 18.4 +/- 26.3 ng./ml. before treatment, 3.4 +/- 3.9 ng./ml. at 6 months, 2.3 +/- 2.3 ng./ml. at 12 months and 4.9 +/- 6.0 ng./ml. at 24 months (1.2 +/- 1.0 ng./ml. for patients with no evidence of disease). Of the patients 15.8% had local failure at 18 to 24 months as determined by positive transrectal ultrasound guided biopsy. Five of 58 patients (8.6%) had persistently elevated prostate specific antigen levels, only 1 of whom had a positive biopsy. Laparoscopic pelvic lymph node dissection with transrectal ultrasound guided implantation is a safe and promising mode of therapy for patients with localized prostate cancer.