Planned, delivered and variable RBE dose difference analysis for a patient cohort with base-of-tongue cancer treated with IMPT

Qianxia Wang; Edgar Gelover Reyes; Alex Stanforth; William Andrew LePain; Haijian Chen; Mingyao Zhu; Katja M. Langen; William Stokes; Soumon Rudra; Mark McDonald; James Edward Bates; Stella Flampouri

arXiv · 2606.11465

Planned, delivered and variable RBE dose difference analysis for a patient cohort with base-of-tongue cancer treated with IMPT

Qianxia Wang·Edgar Gelover Reyes·Alex Stanforth·William Andrew LePain·Haijian Chen·Mingyao Zhu·Katja M. Langen·William Stokes·Soumon Rudra·Mark McDonald·James Edward Bates·Stella Flampouri

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Abstract

Background: To our knowledge, no tools have been installed in clinic for delivered and planned dose differences evaluation. This difference could be large for head and neck patients who suffer the most anatomy changes compared with other treatment sites due to long treatment courses and difficulty in eating. At the same time, variable RBE dose is an increasing concern for proton therapy. The constant RBE 1.1 is widely applied in clinics, however, the real RBE is larger than 1.1 especially at the end of beam range. How they are different and what the influence on plan evaluation are an interesting topic to investigate.

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Qianxia Wang, Edgar Gelover Reyes, Alex Stanforth, William Andrew LePain, Haijian Chen, Mingyao Zhu, Katja M. Langen, William Stokes, Soumon Rudra, Mark McDonald, James Edward Bates, Stella Flampouri. 2026-06-09. Planned, delivered and variable RBE dose difference analysis for a patient cohort with base-of-tongue cancer treated with IMPT. https://arxiv.org/abs/2606.11465

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