MO‐D‐500‐01: Treatment Planning in Proton Therapy

Proton therapy planning strategies differ in many aspects from traditional planning done for photon treatments. Both passive scattered and scanning proton treatment planning systems and protocols must account for proton specific uncertainties to deliver high fidelity plans to the patient. While many uncertainties have been discussed in the literature, clinical implementations of proton treatment planning systems require adequate procedures to address uncertainties. Some uncertainties are constant between passive scattered and scanning systems but other uncertainties, due to the differences in beam delivery methods, necessitate different approaches to accurately deliver the prescribed treatment. For example, range, LET, RBE, and patient position uncertainties are common to all particle therapies but the effects on the delivered treatment are dependent upon the delivery method. Passive scattered delivery techniques must account for field size effects, output factors, hardware uncertainties, air gaps and penumbras. Scanning beams encounter different uncertainties regarding spot size, scanning positional accuracy, beam spot dosimetry, and magnet calibration uncertainties. Learning Objectives: 1. To understand the fundamentals of treatment planning for passive and scanned proton therapy, including Intensity Modulated Proton Therapy 2. To understand the proton specific strategies in treatment planning for passive scattering and scanning 3. To understand uncertainties of proton therapy and their implications on proton treatment planning 4. To understand the limitations of current proton treatment planning techniques.