American brachytherapy society (ABS) recommendations for transperineal permanent brachytherapy of prostate cancer

Abstract

Purpose/Objective: To develop and disseminate the American Brachytherapy Society (ABS) recommendations for the clinical quality assurance and guidelines of permanent transperineal prostate brachytherapy with 125I or 103Pd. Methods and Materials: The ABS formed a committee of experts in prostate brachytherapy to develop consensus guidelines through a critical analysis of published data supplemented by their clinical experience. The recommendations of the panels were reviewed and approved by the Board of Directors of the ABS. Results: Patients with high probability of organ-confined disease are appropriately treated with brachytherapy alone. Brachytherapy candidates with a significant risk of extraprostatic extension should be treated with supplemental external beam radiation therapy (EBRT). Patient selection guidelines were developed. Dosimetric planning of the implant should be carried out for all patients before seed insertion. A modified peripheral loading is preferred. The AAPM TG-43 recommendations requiring a change in prescription dose for 125I sources should be universally implemented. The recommended prescription doses for monotherapy are 145 Gy for 125I and 115–120 Gy for 103Pd. The corresponding boost doses (after 40–50 Gy EBRT) are 100–110 Gy and 80–90 Gy, respectively. Clinical evidence to guide selection of radionuclide ( 103Pd or 125I) is lacking. Post implant dosimetry and evaluation must be performed on all patients. It is suggested that the dose that covers 90% (D 90) and 100% (D 100) of the prostate volume and the percentage of the prostate volume receiving the prescribed dose (V 100) be obtained from a dose-volume histogram (DVH) and reported. Conclusion: Guidelines for appropriate patient selection, dose reporting, and improved quality of permanent prostate brachytherapy are presented. These broad recommendations are intended to be technical and advisory in nature, but the ultimate responsibility for the medical decisions rests with the treating physician. This is a constantly evolving field, and the recommendations are subject to modifications as new data becomes available.