Application of Dose-volume Combined with Equivalent Uniform Dose Optimization in Optimization of OAR in IMRT on Nasopharyngeal Carcinoma

Abstract

Objective To investigate the application of dose-volume (DV) combined with equivalent uniform dose (EUD) in the optimization of organ at risk (OAR) in IMRT on nasopharyngeal carcinoma. Methods We selected 55 patients with nasopharyngeal carcinoma who received IMRT planning in the Department of Oncology, The Affiliated Hospital of Southwest Medical University. The optimization methods were divided into conventional DV optimization and DV and EUD combined optimization. The dosages of the target and OAR after two optimization methods were evaluated. Results There was no significant difference in the prescription dose, homogeneity index or conformity index between the two groups (all P > 0.05). We found that the mean OAR doses for DV and EUD combined optimization were significantly lower than those for conventional DV optimization (all P < 0.001). Conclusion DV and EUD combined optimization is successfully applied to the optimization of OAR in IMRT on nasopharyngeal carcinoma, and we give an evaluation methods for the dosimetry of organs at risk in IMRT, in order to reduce the influence of subjective factors.

Keywords

• dose-volume optimization
• equivalent uniform dose optimization
• imrt
• nasopharyngeal carcinoma (npc)