Verification using in vivo optically stimulated luminescent dosimetry of the predicted skin surface dose in patients receiving postmastectomy radiotherapy

The purpose of this study was to evaluate whether dose the skin surface underneath bolus, accurately predicted by a 3D treatment planning system (TPS) in patients receiving 50 Gy/25# postmastectomy radiotherapy (PMRT) using optically stimulated luminescent dosimetry (OSLD) for verification. In vivo OSLDs performed 20 consecutive PMRT. An array 9 were applied chest wall or neobreast grid arrangement. Dosimetry data recorded on 3 separate fractions, averaged, and extrapolated 25 fractions. On TPS, calculated departmental algorithm at points corresponding OSLDs. mean within patient difference between planned measured each Bland-Altman limits agreement used quantify extent agreement. Paired t-tests test evidence systematic bias point. coefficient variation OSLD readings per low 8 (≤4.4%) demonstrating comparable received fraction these points. ratio (IVME OSLD) TPS ranged 0.97 0.99 across all (standard deviation range 0.05 0.08). IVME but <1. This practical feasible assessment only fractions facilitates quality assurance predicting under bolus.