Permanent prostate brachytherapy preplanned technique: The modern Seattle method step-by-step and dosimetric outcomes.

PURPOSE: To describe, step-by-step, the current Seattle preplan technique, and report the dosimetric outcomes on 1,131 consecutively such treated prostate brachytherapy patients. METHODS AND MATERIALS: One thousand one hundred thirty one patients with prostate cancer were treated with iodine-125 (I-125), palladium-103 (Pd-103), or cesium-131 (Cs-131) using a preplanned template-guided transrectal ultrasound-guided approach between January 2005 and August 2007. Day one computed tomography (CT) scans were taken for postimplantation dose-volume histogram evaluations. Postoperative prostate contours were drawn by one author (DN) on CT images taken on postoperative clay one, RESULTS: The volume of prostate receiving 100% of prescription dose (V-100) and percent dose to 90% of the prostate (%D-90) were 95% and 106% for 558 monotherapy I-125 implants, 91% and 102% for 327 Pd-103 implants, and 97% and 111.5% for 13 Cs-131 implants, respectively. The median V-100 and percent D-90 were 91% and 101% for five boost I-125 implants, 92% and 104% for 228 boost Pd-103 implants. The median rectal volume receiving 100% of prescription dose (RV100) for I-125, Pd-103, and Cs-131 monotherapy implants were 0.3, 0.13, and 0.38 cc, and for I-125 and Pd-103 boost implants were 0.16 and 0.13 cc, respectively. No patient received an RV100 of >0.92 cc. CONCLUSIONS: Modern preplanned template and Ultrasound-guided prostate brachytherapy can consistently result in excellent prostate dosimetry and rectal sparing. (C) 2009 American Brachytherapy Society. All rights reserved.