(S031) A Phantom-Based Simulator Approach to Improving the Quality of Prostate Brachytherapy Training

Nikhil G. Thaker, MD, Rajat J. Kudchadker, PhD, David A. Swanson, MD, Jeffrey M. Albert, MD, MPH, Usama Mahmood, MD, Thomas J. Pugh, MD, Nicholas S. Boehling, MD, Teresa L. Bruno, CMD, Bradley R. Prestidge, MD, Juanita M. Crook, MD, Brett W. Cox, MD, Louis Potters, MD, Brian J. Moran, MD, Mira Keyes, MD, Deborah A. Kuban, MD, Steven J. Frank, MD; UT MD Anderson Cancer Center

Purpose and Objectives: Permanent prostate brachytherapy (PPB) is a well-established treatment for localized prostate cancer. The future of PPB relies upon the quality training of future residents; however, current training requirements are frequently inadequate. Our objective was to design and implement a unique training program that utilized a phantom-based simulator to teach the process of quality assurance (QA) and improve PPB education.

Materials and Methods: Trainees in our simulator program were radiation oncologists, radiation oncology residents, and fellows of the American Brachytherapy Society. The simulator program emphasized six core areas of PPB QA: patient selection, simulation, treatment planning, implant technique, treatment evaluation, and outcome assessment. Trainees used the iodine-125 preoperative treatment planning technique to implant their prostate phantoms using a transrectal ultrasound (TRUS) device. Preimplant and postimplant dosimetric parameters were compared and correlated using regression analyses.

Results: Thirty-one trainees successfully completed the simulator training program. The mean phantom prostate size, number of seeds, and total activity were consistent among trainees, with some differences based on phantom heterogeneity. All trainees met the V100 > 95% objective both preimplant and postimplant. V150 and D90 were higher in the postimplant setting as compared with preimplant, and the standard deviations of all parameters were slightly higher postimplant. The mean planned D90 was 183.6 Gy (range: 162.6–196.5 Gy), while the postimplant D90 achieved was 191.2 Gy (range: 158.5–215.4 Gy), suggesting that trainees achieved excellent heterogeneity control. Preimplant and postimplant V100 and V150 vs TRUS prostate volume showed strong correlation (r = 0.99 for V100 and r = 0.59 for V150). A comparison of preimplant and postimplant V100 and V150 similarly demonstrated good correlation (r = 0.99 for V100 and r = 0.37 for V150). As expected, the range of V100 values was quite narrow and very closely related to the initial prostate volume. The V150 values had a broader range and slightly lower concordance with prostate gland size, likely due to variations in planning, implantation, and trainee experience.

Conclusions: Analysis of implants from the phantom-based simulator shows that there is a high degree of consistency among trainees and that implants are uniformly high-quality with respect to parameters used in actual clinical practice. This training program provides a valuable educational opportunity for those learning the PPB process and likely accelerates the learning curve inherent to PPB. Prostate phantom implantation can be a valuable first step in the acquisition of the required skills to safely perform PPB. Given the current healthcare environment and increased scrutiny on benefits, costs, and impact of technology on cancer care, our approach to PPB training will impact the future of patient care, and the phantom-based simulator is an excellent tool to educate the next generation of brachytherapists.

Proceedings of the 96th Annual Meeting of the American Radium Society - americanradiumsociety.org