title: [The effect of metformin on responses to chemotherapy and survival in stage IV colorectal cancer with diabetes].
abstract: OBJECTIVE
  Metformin is known to lower the risk of cancer and cancer mortality. However, the effect of metformin in stage IV colorectal cancer (CRC) patients with diabetes mellitus (DM) remains unknown. The aim of this study was to evaluate the effect of metformin on tumor response and survival in stage IV CRC patients with DM.
  
  
  METHODS
  We identified 106 patients who were diagnosed with both stage IV CRC and DM (81 patients who underwent palliative chemotherapy and 25 patients who underwent curative resection). Retrospective data of each patient's clinical characteristics, tumor response, and survival rate were compared between two groups of patients who either were or were not administered metformin.
  
  
  RESULTS
  For the palliative chemotherapy group, tumor response, change in target lesion size, progression free survival rate, and overall survival rate were not significantly different between the metformin group and the non-metformin group on univariate and multivariate analysis. For the curative resection patient group, metformin use was associated with increased disease free survival on univariate analysis (p=0.012) and multivariate analysis (hazard ratio, 0.024; 95% CI 0.001-0.435; p=0.010), but not with overall survival.
  
  
  CONCLUSIONS
  Metformin use in stage IV CRC patients with diabetes was shown to be associated with a lower risk of tumor recurrence after curative resection.
authors.affiliation: Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Dong Jun
authors.initials: DJ
authors.lastname: Lee
authors.forename: Bun
authors.initials: B
authors.lastname: Kim
authors.forename: Jin Ha
authors.initials: JH
authors.lastname: Lee
authors.forename: Su Jung
authors.initials: SJ
authors.lastname: Park
authors.forename: Sung Pil
authors.initials: SP
authors.lastname: Hong
authors.forename: Jae Hee
authors.initials: JH
authors.lastname: Cheon
authors.forename: Tae Il
authors.initials: TI
authors.lastname: Kim
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000401:mortality* / Q000473:pathology; D003920:Diabetes Mellitus / Q000188:drug therapy*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D010166:Palliative Care; D012189:Retrospective Studies; D015996:Survival Rate
chemical_list: D000970:Antineoplastic Agents; D007004:Hypoglycemic Agents; D008687:Metformin