title: Defective mismatch repair status as a prognostic biomarker of disease-free survival in stage III colon cancer patients treated with adjuvant FOLFOX chemotherapy.
abstract: OBJECTIVE
  Adding oxaliplatin to adjuvant 5-fluorouracil (5-FU) chemotherapy improves 3-year disease-free survival (DFS) after resection of stage III colon cancer. Several studies suggest that patients with tumors exhibiting defective mismatch repair (MMR) do not benefit from adjuvant 5-FU chemotherapy, but there are few data on 5-FU-oxaliplatin (FOLFOX) adjuvant chemotherapy in this setting. The aim of this study was to evaluate the prognostic value of MMR status for DFS in patients with stage III colon cancer receiving adjuvant FOLFOX chemotherapy.
  
  
  METHODS
  MMR status was determined by microsatellite instability testing or immunohistochemistry in 303 unselected patients with stage III colon cancer receiving adjuvant FOLFOX chemotherapy in 9 centers. Cox proportional hazards models were used to examine the association between MMR status and 3-year DFS.
  
  
  RESULTS
  The 3-year DFS rate was significantly higher in the 34 patients (11.2% of the study population) with defective MMR tumors (90.5%) than in patients with proficient MMR tumors (73.8%; log-rank test; HR = 2.16; 95% CI, 1.09-4.27; P = 0.027). In multivariate analysis, MMR status remained an independent significant prognostic factor for DFS (HR = 4.48; 95% CI, 1.34-14.99; P = 0.015).
  
  
  CONCLUSIONS
  MMR status is an independent prognostic biomarker for DFS in patients with stage III colon cancer receiving adjuvant FOLFOX chemotherapy.
authors: Department of Gastroenterology and Digestive Oncology, Georges Pompidou European Hospital, AP-HP, Paris, France.
authors: Aziz
authors: A
authors: Zaanan
authors: Jean-François
authors: JF
authors: Fléjou
authors: Jean-François
authors: JF
authors: Emile
authors: Guetz Gaëtan
authors: GG
authors: Des
authors: Peggy
authors: P
authors: Cuilliere-Dartigues
authors: David
authors: D
authors: Malka
authors: Cédric
authors: C
authors: Lecaille
authors: Pierre
authors: P
authors: Validire
authors: Christophe
authors: C
authors: Louvet
authors: Philippe
authors: P
authors: Rougier
authors: Aimery
authors: A
authors: de Gramont
authors: Franck
authors: F
authors: Bonnetain
authors: Françoise
authors: F
authors: Praz
authors: Julien
authors: J
authors: Taïeb
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor; D017024:Chemotherapy, Adjuvant; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000235:genetics*; D053843:DNA Mismatch Repair; D018572:Disease-Free Survival; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use; D006801:Humans; D002955:Leucovorin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009944:Organoplatinum Compounds / Q000627:therapeutic use; D011379:Prognosis; D016016:Proportional Hazards Models
chemical_list: D014408:Biomarkers, Tumor; D009944:Organoplatinum Compounds; D002955:Leucovorin; D005472:Fluorouracil