Abstract

Info

Title:: Application of partial arc volumetric modulated arc therapy for central lung cancer

Author(s):: LIU Jianping; YANG Haifang; WANG Zhiwu; ZHANG Xiaobin; JIANG Bin; WANG Rui; Department of Radiation Oncology, Tangshan People’s Hospital, Tangshan 063001, China

Keywords:: Keywords: central lung cancer; volumetric modulated arc therapy; avoiding sector function

Abstract:: Abstract: Objective To explore the feasibility of avoiding sector function to reduce the dose to lungs in volumetric modulated arc therapy (VMAT) for central lung cancer. Methods Three plans avoiding sector function were generated for 16 patients with central lung cancer, including partial arc VMAT (P-VMAT) plan, full-arc VMAT plan and 5-field intensity-modulated radiotherapy (IMRT) plan. The conformity index and homogeneity index of the planning target volume, the V5, V20, V30 of lungs, mean lung dose, and the doses to heart, spinal cord and esophagus were compared, and the execution efficiency of plans were evaluated. Results All the 3 plans met the clinical requirement. P-VMAT plan showed a slightly decreased conformity index of target areas and a declined dose to lungs, especially the V5 of lungs, as comparison with full-arc VMAT plan, and no significant differences were found in the other dosimetry indicators of target areas and the dose to the other organs-at-risk. Compared with IMRT plan, P-VMAT plan increased the dosimetry indicators of target areas, significantly decreased the dose to high-dose area of lung but slightly increased the V5 of lungs, and shortened the treatment time. Conclusion P-VMAT plan avoiding sector function which is suitable for the radiotherapy for central lung cancer can reduce the dose to low dose area in lungs and maintain other advantages of VMAT.