title: Role of radiotherapy for pancreatobiliary neuroendocrine tumors.
abstract: OBJECTIVE
  We investigated the role of radiotherapy (RT) for pancreatobiliary neuroendocrine tumors (PB-NETs).
  
  
  METHODS
  We identified 9 patients with PB-NETs who received RT between January 2005 and March 2012. Of these 9 patients, 4 were diagnosed with NETs in the pancreas and 5 were diagnosed with NETs in the gallbladder. All patients received RT to the primary tumor or resection bed with a median total irradiation dose of 50.4 Gy, with or without chemotherapy.
  
  
  RESULTS
  The tumor response rate and tumor control rate in the RT field were 60% and 100 %, respectively. All 4 patients who underwent surgery had no evidence of disease in the RT field. Of the 5 patients who received RT to the primary gross tumor, 1 had complete response, 2 had partial response, and 2 had stable disease in the RT field. The median time to progression was 11 months. Of the 9 patients, four patients had no progression, and 5 patients had progression of disease (locoregional, 2; distant, 2; locoregional/distant, 1). Of the 4 patients without progression, 3 were treated with RT in adjuvant or neoadjuvant setting, and one received RT to primary tumor. One patient experienced radiation-induced duodenitis at 3 months after concurrent chemoradiation without treatment-related mortality.
  
  
  CONCLUSIONS
  RT can yield local control for advanced PB-NETs. RT should be considered an essential part of multimodality treatment in management of advanced PB-NETs.
authors.affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jeongshim
authors.initials: J
authors.lastname: Lee
authors.forename: Jinhyun
authors.initials: J
authors.lastname: Choi
authors.forename: Chihwan
authors.initials: C
authors.lastname: Choi
authors.forename: Jinsil
authors.initials: J
authors.lastname: Seong
keywords: Neuroendocrine tumors; Radiotherapy; Treatment outcome