SUMMARY
Intensity modulated proton therapy (IMPT) is a radiation therapy treatment modality that offers superior dose conformity and normal tissue sparing in the treatment of a variety of cancers. IMPT may deliver simultaneous integrated boost (SIB) to dominant intraprostatic lesions (DILs) detected by multiparametric MRI (mpMRI) to improve tumor control in prostate patients. DIL-SIB delivered using traditional photon therapy techniques has been demonstrated to achieve better clinical outcomes. IMPT can deliver a larger dose to the DIL than photons but is more susceptible to dosimetric variation from interfractional anatomic changes. The purpose of this thesis is to evaluate the efficacy of IMPT DIL-SIB plans and their sensitivity to daily anatomy changes through calculation of tumor control probability (TCP) and normal tissue complication probability (NTCP).