Volumetric Arc Therapy Seems More Promising for Sparing Organs at Risk in Adjuvant Postoperative Radiotherapy for Pancreatic Adenocarcinoma than Step-and-Shoot Intensity-Modulated Radiotherapy

Abstract

OBJECTIVEThe aim of the present study was to determine if volumetric modulated arc therapy (VMAT) provided superior dose distribution than intensity-modulated radiotherapy (step-and-shoot; ssIMRT) based on target volume coverage and organs at risk (OARs) doses in postoperative radiotherapy for pancreatic cancer patients. METHODSNew 4-dimensional computed tomography plans for 10 pancreatic cancer patients were created. The ssIMRT plans had 6 coplanar fields (330-0-30-60-90°) and VMAT plans were generated with 2 268-92° arcs. RESULTS VMAT CONCLUSIONVMAT provided more effective protection for bilateral kidneys and small intestine with better OAR doses, as well as for liver, with reduced high-dose volumes in this cohort. This could be investigated as more tolerable concurrent radiochemotherapy treatment with better OAR preservation.