K Senthilkumar1, K J Maria Das2. 1. Department of Medical Physics, Karnataka Cancer Therapy and Research Institute, Hubli, Karnataka; Research and Development Centre, Bharathiar University, Coimbatore, Tamil Nadu, India. 2. Research and Development Centre, Bharathiar University, Coimbatore, Tamil Nadu; Department of Radiotherapy, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, India.
Abstract
PURPOSE: Nowadays, most of the radiotherapy (RT) treatment planning systems (TPSs) uses dose or dose-volume (DV)-based cost functions for Intensity modulated radiation therapy (IMRT) fluence optimization. Recently, some of the TPSs incorporated biological-based cost function for IMRT optimization. Most of the previous studies compared IMRT plans optimized using biological-based and DV-based cost functions in two different TPSs. Hence, the purpose of the study is to compare equivalent uniform dose (EUD)-based and DV-based IMRT plans generated using the same TPS. MATERIALS AND METHODS: Twenty patients with prostate cancer were retrospectively selected for this study. For each patient, two IMRT plans were generated using EUD-based cost function (EUD_TP) and DV-based cost (DV_Treatment Plan (TP)), respectively. The generated IMRT plans were evaluated using both physical and biological dose evaluation indices. RESULTS: Biological-based plans ended up with a highly inhomogeneous target dose when compared to DV-based plans. For serial organs, Dnear-max or D2%(Gy) of EUD-based plans showed significant difference with DV-based plans (P = 0.003). For both rectum and bladder, there was a significant difference in mean dose and D30%(Gy) dose between EUD-based plans and DV-based plans. CONCLUSION: In this study, we decoupled the influence of optimization parameters from the potential use of EUD-based cost functions on plan quality by generating both plans in the same TPS.
PURPOSE: Nowadays, most of the radiotherapy (RT) treatment planning systems (TPSs) uses dose or dose-volume (DV)-based cost functions for Intensity modulated radiation therapy (IMRT) fluence optimization. Recently, some of the TPSs incorporated biological-based cost function for IMRT optimization. Most of the previous studies compared IMRT plans optimized using biological-based and DV-based cost functions in two different TPSs. Hence, the purpose of the study is to compare equivalent uniform dose (EUD)-based and DV-based IMRT plans generated using the same TPS. MATERIALS AND METHODS: Twenty patients with prostate cancer were retrospectively selected for this study. For each patient, two IMRT plans were generated using EUD-based cost function (EUD_TP) and DV-based cost (DV_Treatment Plan (TP)), respectively. The generated IMRT plans were evaluated using both physical and biological dose evaluation indices. RESULTS: Biological-based plans ended up with a highly inhomogeneous target dose when compared to DV-based plans. For serial organs, Dnear-max or D2%(Gy) of EUD-based plans showed significant difference with DV-based plans (P = 0.003). For both rectum and bladder, there was a significant difference in mean dose and D30%(Gy) dose between EUD-based plans and DV-based plans. CONCLUSION: In this study, we decoupled the influence of optimization parameters from the potential use of EUD-based cost functions on plan quality by generating both plans in the same TPS.
Authors: Philipp Hoegen; Clemens Lang; Sati Akbaba; Peter Häring; Mona Splinter; Annette Miltner; Marion Bachmann; Christiane Stahl-Arnsberger; Thomas Brechter; Rami A El Shafie; Fabian Weykamp; Laila König; Jürgen Debus; Juliane Hörner-Rieber Journal: Front Oncol Date: 2020-12-09 Impact factor: 6.244