MO-E-BRCD-01: Proton Treatment Planning Issues

Proton treatment planning involves many issues that affect the accuracy and robustness of treatment planning and delivery. Some issues such as patient setup uncertainty and CT number calibration are common with photon planning but have potentially greater effects on the treatment plan simulation and delivery for proton. Other issues such as range uncertainty and LET and RBE variations are unique to particle therapy. The complications of proton treatment planning have been well documented in the literature but there are multiple planning methods developed by clinics to reduce or avoid proton dosimetry errors in treatment delivery. Additionally, error reduction methods are dependent upon the delivery Method: scattering or scanning, single-field optimization or multi-field optimization. This educational session will discuss the documented proton treatment planning issues and the methods developed in three different clinical centers to minimize or eliminate the errors associated with the issues for various treatment sites and proton treatment modalities. LEARNING OBJECTIVES: 1. Understand the issues associated with proton treatment planning and the effects of range uncertainty, LET variations, and setup uncertainties. 2. Understand the differences of photon and proton treatment planning issues. 3. Understand the methods developed to reduce errors in proton treatment planning and delivery at three different centers.