title: Risk factors for vertebral compression fractures in preoperative chemoradiotherapy with gemcitabine for pancreatic cancer.
abstract: OBJECTIVE
  Preoperative chemoradiotherapy (CRT) with gemcitabine (GEM) for pancreatic cancer is often accompanied by vertebral compression fractures (VCFs). This study aimed to establish the incidence of VCFs and identify the related risk factors (RFs) to elucidate how to decrease the overall incidence of VCF.
  
  
  METHODS
  We investigated 220 patients with resectable or borderline-resectable pancreatic cancers who had completed preoperative CRT between 2006 and 2011. The RFs associated with VCF were analyzed in a total of 1308 thoracolumbar vertebral bodies.
  
  
  RESULTS
  Thirty-seven VCFs occurred in 25 patients (11%); the cumulative incidence at two years was 18.9%. Univariate analysis revealed female sex, age and high daily GEM concentration during radiotherapy as RFs for VCF. The multivariate mixed effects logistic regression model demonstrated that the most responsible factor was radiation dose (p<0.001). We estimated the radiation condition resulting in a fracture incidence of ⩽5% by counting the patient's number of the three RFs. For patients with three factors, the mean vertebral dose was 22.0 Gy.
  
  
  CONCLUSIONS
  The RFs for VCF after CRT were identified. The side effect of VCF might be avoided by regulating the radiation dose to neighboring vertebral bodies after considering the RFs.
authors.affiliation: Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Otani
authors.affiliation: Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan. Electronic address: teshima-te@mc.pref.osaka.jp.
authors.forename: Teruki
authors.initials: T
authors.lastname: Teshima
authors.affiliation: Department of Cancer Epidemiology and Prevention Center for Cancer Control and Statistics, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Ito
authors.affiliation: Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Kawaguchi
authors.affiliation: Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Konishi
authors.affiliation: Department of Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Department of Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ohigashi
authors.affiliation: Department of Orthopedic Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Oshima
authors.affiliation: Department of Orthopedic Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Araki
authors.affiliation: Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Kinji
authors.initials: K
authors.lastname: Nishiyama
authors.affiliation: Department of Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Ishikawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000964:Antimetabolites, Antineoplastic / Q000009:adverse effects*; D059248:Chemoradiotherapy / Q000009:adverse effects; D003841:Deoxycytidine / Q000009:adverse effects / Q000031:analogs & derivatives*; D004812:Epidemiologic Methods; D005260:Female; D050815:Fractures, Compression / Q000139:chemically induced*; D005598:Fractures, Spontaneous / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000188:drug therapy*; D011183:Postoperative Complications / Q000139:chemically induced; D011300:Preoperative Care / Q000379:methods; D016103:Spinal Fractures / Q000139:chemically induced*; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D003841:Deoxycytidine; D000093542:Gemcitabine
keywords: Mixed effects logistic regression model; Pancreatic cancer; Preoperative chemoradiotherapy; Vertebral compression fracture