SU‐E‐T‐809: A Grading‐Study Based Tool to Assist in the Choice of Treatment Modality

Purpose: It is common for radiation oncologists (ROs) today to have a mixed arsenal of radiotherapy treatment modalities at their disposal. To optimize a clinic's use of its different treatment modalities, while at the same time giving every patient an optimal treatment, is not a trivial task. The purpose of this study was to give ROs a tool to choose between available modalities. This would help to ensure that the most advanced modality is available for the patients that really benefits from this treatment, and allow for a more optimal use of the clinic's assets. This study included different modalities such as 3DCRT, step‐and‐shoot IMRT, and helical tomotherapy. Methods: Twenty‐three patients that had received treatment for tumours in different anatomical regions with the tomotherapy system were chosen. All tomotherapy plans were converted into seven‐beam step‐ and‐shoot IMRT plans using the treatment planning system SharePlan. When feasible, conventional 3DCRT plans were also created by our most experienced planner. A side‐by‐side demonstration of every patient's plans was performed. Ten experienced ROs were individually asked to compare and grade the plans. The results were statistically analysed by using Sign test. Results: The results show that for all regions combined, the TT plans were considered somewhat better than the IMRT plans and much better than the 3DCRT plans (p<0.05). Divided into the different anatomical regions, however, the perceived superiority of the TT plans, as compared to step‐and‐shoot IMRT, was only significant for the patients treated in the abdominal and pelvic region. Conclusions: Based on the ROs grading scores obtained in the present study, priority for treatment with the TT system should be given to patients with tumours in the abdominal and pelvic region. Other factors, such as the overall treatment time and the machine occupancy, may also be important for the final choice of treatment. © 2011, American Association of Physicists in Medicine. All rights reserved.