title: The carcinogenicity of alendronate in patients with osteoporosis: evidence from cohort studies.
abstract: BACKGROUND
  Alendronate may relate to the incidence of cancers, especially esophageal and colon cancer. But the results are inconsistent in different studies.
  
  
  OBJECTIVE
  To quantify the association between the use of alendronate and the occurrence of different types of cancer.
  
  
  METHODS
  We searched Embase, Pubmed, CENTRAL, SIGLE and clinicaltrials.gov, up to 2014 June.
  
  
  METHODS
  Cohort studies reporting association between alendronate or bisphosphonate therapy including alendronate in patients with osteoporosis and risk of cancer were selected by two authors.
  
  
  METHODS
  Two authors independently extracted the data. The Chi-square test and the I-square test were used for testing heterogeneity between studies.
  
  
  RESULTS
  Eight cohort studies were included in the meta-analysis. Meta-analysis result manifested that alendronate significantly increased the incidence of lung cancer (HR 1.23, 95%CI 1.03 to 1.47, P value = 0.03), nevertheless, there was no significant difference after we excluded either Lee's 2012 study (HR 1.17, 95%CI 0.95 to 1.44, P value = 0.13) or Chiang's 2012 study (HR 1.47, 95%CI 1 to 2.17, P value = 0.05). For the incidence of colorectal cancer, no significant difference occurred (HR 0.91, 95%CI 0.74 to 1.13, P value = 0.39), but there was a positive relationship when we used fixed model (HR 0.85, 95%CI 0.78 to 0.93, P value = 0.004). For the incidence of liver cancer, there was no significant difference (HR 1.36, 95%CI 0.9 to 2.04, P value = 0.14), however, the result changed after we excluded Chiang's 2012 study (HR 1.69, 95%CI 1.03 to 2.77, P value = 0.04). There was no significant difference in other types of cancer.
  
  
  CONCLUSIONS
  Based on current evidences, alendronate therapy may be associated with a high risk of lung cancer, may with an excess risk of liver cancer, a low risk of colorectal and no related risk of other cancers.
authors.affiliation: Department of Orthopaedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, People's Republic of China.
authors.forename: Ling-Xiao
authors.initials: LX
authors.lastname: Chen
authors.affiliation: Department of Orthopaedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, People's Republic of China.
authors.forename: Guang-Zhi
authors.initials: GZ
authors.lastname: Ning
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China.
authors.forename: Zhi-Rui
authors.initials: ZR
authors.lastname: Zhou
authors.affiliation: Department of Orthopaedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, People's Republic of China.
authors.forename: Yu-Lin
authors.initials: YL
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, People's Republic of China.
authors.forename: Di
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Orthopaedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, People's Republic of China.
authors.forename: Qiu-Li
authors.initials: QL
authors.lastname: Wu
authors.affiliation: Internal Medicine of Traditional Chinese Medicine Department, Jing 'an District Central Hospital of Shanghai, NO. 259, Xikang Road, 200040, Shanghai, People's Republic of China.
authors.forename: Tian-Song
authors.initials: TS
authors.lastname: Zhang
authors.affiliation: Comprehensive Cancer Center of Drum-Tower Hospital, Medical School of Nanjing University, Clinical Cancer Institute of Nanjing University, 321 Zhongshan Road, Nanjing, 210008, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Department of Orthopaedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, People's Republic of China.
authors.forename: Shi-Qing
authors.initials: SQ
authors.lastname: Feng
mesh_terms: D019386:Alendronate / Q000009:adverse effects*; D050071:Bone Density Conservation Agents / Q000009:adverse effects; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000139:chemically induced / Q000453:epidemiology; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000139:chemically induced / Q000453:epidemiology; D008175:Lung Neoplasms / Q000139:chemically induced / Q000453:epidemiology; D009369:Neoplasms / Q000139:chemically induced* / Q000453:epidemiology*; D010024:Osteoporosis / Q000188:drug therapy*; D017594:Publication Bias; D013274:Stomach Neoplasms / Q000139:chemically induced / Q000453:epidemiology
chemical_list: D050071:Bone Density Conservation Agents; D019386:Alendronate