Upper gastrointestinal complications associated with gemcitabine-concurrent proton radiotherapy for inoperable pancreatic cancer

Little is known about acute upper gastrointestinal (GI) complications associated with gemcitabine-concurrent proton radiotherapy (GPT) for inoperable pancreatic cancer. We investigated acute GI complications following GPT in patients with inoperable pancreatic cancer using small-bowel endoscopy. This prospective single center observational study was conducted at the Hyogo Ion Beam Medical Center from January 2010 to January 2012. Ninety-one patients who had clinically and medically inoperable pancreatic cancer treated by GPT were analyzed. Endoscopic examinations were performed before and after GPT to clarify the incidence rates of radiation-induced ulcers, GI hemorrhage, and GI perforation associated with GPT. Post-treatment endoscopic examinations revealed that 45 (49.4 %) patients had radiation-induced ulcers in the stomach and duodenum. Of those, many ulcerative lesions were found in the lower stomach (51 %) and horizontal part of the duodenum (39 %), regardless of the primary tumor site in the pancreas. Neither GI hemorrhage, nor perforation, was found in post-treatment endoscopy examinations. Approximately half of the patients treated with GPT for inoperable pancreatic cancer exhibited radiation-induced ulcers in the stomach and duodenum.