Duodenal Sparing Stereotactic Body Radiation Therapy For Locally-Advanced Pancreatic Cancer: Technique, Toxicity, and Local Response

Purpose/Objective(s): The proximity of the pancreas to bowel presents a unique challenge for pancreatic cancer SBRT. This study explores the safety and effectiveness of a novel approach optimizing pancreatic tumor coverage and duodenal sparing. Materials/Methods: From 2010 to 2012, twenty-four patients with locally advanced pancreatic cancer (21 head/3 body) were treated with initial chemotherapy (Gemcitabine or 5-FU/Cisplatin) for 2-6 months. All underwent endoscopic ultrasound-guided fiducial placement in and around the tumor and had a 4D treatment planning CT scan with oral contrast. This CTwas used in conjunction with EUS findings, PET, and biphasic CT scans to identify the Gross Tumor Volume (GTV) in the expiration phases. The planning target volume (PTV) was created by expanding the GTV by 2 mm. Dose-volume histogram (DVH) endpoints were constructed, keeping V7/15/20 (stomach/duodenum volumes that receive 7 Gy/15 Gy/ 20 Gy)