ROLE OF INTERSTITIAL RADIOTHERAPY IN THE MANAGEMENT OF CLINICALLY ORGAN-CONFINED PROSTATE-CANCER - THE JURY IS STILL OUT

Purpose and Design: To discuss the evolution of the use of brachythera py in the treatment of clinically organ-confined prostate cancer and t o review modern techniques, results of therapy, and optimal patient se lection criteria. Results: Using modern localization and immobilizatio n techniques, interstitial prostate radiotherapy for patients with a p rostate-specific antigen (PSA) level less than 10 ng/mL yields an at l east 87% rate of freedom from biochemical relapse at 3 years, which is numerically equivalent to results achieved with external-beam radioth erapy or radical prostatectomy. With a minimum median follow-up time o f 24 months, 81% to 85% (2-year actuarial and 3-year crude) potency ra tes have been reported concomitant with 2-year actuarial rates of 12% for grade greater than or equal to 2 rectal complications and 10% for grade greater than or equal to 3 urethral complications. Conclusion: T he combination of clinical stage, PSA level, and biopsy Gleason sum al lows for selection of patients with the highest probability of having all of the prostate cancer encompassed by the high-dose implant volume , while simultaneously respecting the normal-tissue tolerance doses of the juxtaposed normal tissues (rectum and bladder), In particular, pa tients with nonpalpable (Tie) lesions, a biopsy Gleason sum less than or equal to 6 (ideally less than or equal to 4), and a PSA level less than 10 ng/mL represent the optimal implant candidates, Differential l oading of the implant away from the geometric center and not accepting patients with large prostate glands (greater than or equal to 60 cm(3 )) or history of a transurethral resection of the prostate (TURF) as i mplant candidates, may reduce urethral toxicity, Further follow-up eva luation of prostate cancer patients treated with interstitial radiothe rapy will verify if favorable potency preservation rates and rates of freedom from biochemical failure equivalent to those achieved with rad ical prostatectomy or external-beam radiation therapy are maintained. (C) 1996 by American Society of Clinical Oncology.