Dose to medium in head and neck radiotherapy: Clinical implications for target volume metrics

Abstract

Background and purpose: In radiotherapy dose calculation, advanced type-B dose calculation algorithms can calculate dose to medium (Dm ), as opposed to Type-B algorithms which compute dose to varying densities of water (Dw ). We investigate the impact of Dm on calculated dose and target coverage metrics in head and neck cancer patients. Methods and materials: We reviewed 27 successfully treated (disease free at two-years post-(chemo)radiotherapy) human papillomavirus-associated (HPV) oropharyngeal cancer (ONC) patients treated with IMRT. Doses were calculated with Type-B and Linear Boltzman Transport Equation (LBTE) algorithms in a commercial treatment planning system, with the treated multi..