Feasibility study of volumetric modulated arc therapy with constant dose rate for endometrial cancer

Journal Article · Tue Oct 01 04:00:00 EDT 2013 · Medical Dosimetry

DOI:https://doi.org/10.1016/J.MEDDOS.2013.04.001· OSTI ID:22262834

Yang, Ruijie ^[1]; Wang, Junjie ^[1]; Xu, Feng ^[2]; Li, Hua ^[3]; Zhang, Xile ^[1]

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1. Department of Radiation Oncology, Peking University Third Hospital, Beijing (China)
2. Department of Biomedical Engineering, Peking University Third Hospital, Beijing (China)
3. Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing (China)

To investigate the feasibility, efficiency, and delivery accuracy of volumetric modulated arc therapy with constant dose rate (VMAT-CDR) for whole-pelvic radiotherapy (WPRT) of endometrial cancer. The nine-field intensity-modulated radiotherapy (IMRT), VMAT with variable dose-rate (VMAT-VDR), and VMAT-CDR plans were created for 9 patients with endometrial cancer undergoing WPRT. The dose distribution of planning target volume (PTV), organs at risk (OARs), and normal tissue (NT) were compared. The monitor units (MUs) and treatment delivery time were also evaluated. For each VMAT-CDR plan, a dry run was performed to assess the dosimetric accuracy with MatriXX from IBA. Compared with IMRT, the VMAT-CDR plans delivered a slightly greater V{sub 20} of the bowel, bladder, pelvis bone, and NT, but significantly decreased the dose to the high-dose region of the rectum and pelvis bone. The MUs decreased from 1105 with IMRT to 628 with VMAT-CDR. The delivery time also decreased from 9.5 to 3.2 minutes. The average gamma pass rate was 95.6% at the 3%/3 mm criteria with MatriXX pretreatment verification for 9 patients. VMAT-CDR can achieve comparable plan quality with significant shorter delivery time and smaller number of MUs compared with IMRT for patients with endometrial cancer undergoing WPRT. It can be accurately delivered and be an alternative to IMRT on the linear accelerator without VDR capability.

• OSTI ID: 22262834
• Journal Information: Medical Dosimetry, Journal Name: Medical Dosimetry Journal Issue: 3 Vol. 38; ISSN 0958-3947
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
COMPARATIVE EVALUATIONS
EXTERNAL BEAM RADIATION THERAPY
LINEAR ACCELERATORS
NEOPLASMS
RECTUM