title: Efficacy of triplet combination chemotherapy with oxaliplatin, irinotecan and capecitabine (OCX) in metastatic colorectal cancer in relation to RAS/RAF mutation status: results of a retrospective analysis.
abstract: BACKGROUND
  The triplet combination of fluorouracil, oxaliplatin and irinotecan for metastatic colorectal cancer improves efficacy at the cost of increased toxicity. Preliminary reports indicate that triplet combination regimens might improve outcome in the RAS/RAF-mutated subgroup.
  
  
  METHODS
  This retrospective analysis included 25 patients with metastatic colorectal cancer, who received treatment with OCX (oxaliplatin, irinotecan, capecitabine). The regimen consisted of oxaliplatin 70 mg/m2 on days 1 and 15, irinotecan 100 mg/m2 on days 8 and 22, and capecitabine 1,400 mg/m2 on days 1-29 every 5 weeks. KRAS, NRAS, and BRAF mutations were determined by Sanger sequencing.
  
  
  RESULTS
  23 patients received at least 1 cycle and were evaluable for efficacy. In 10 patients, a KRAS or BRAF mutation was detected. Partial remission rate was 61%, median progression-free survival 9.8 months, and median overall survival 32.9 months for all evaluable patients. No difference in efficacy was detected between the RAS/RAF wild-type and the mutant group. OCX was well tolerated with no grade 3/4 haematological events. Diarrhoea was the major non-haematological toxicity (24% grade 3).
  
  
  CONCLUSIONS
  In this retrospective analysis, triplet chemotherapy with OCX was well tolerated and achieved encouraging efficacy in metastatic colorectal cancer irrespective of RAS/RAF mutation status.
authors.affiliation: Division of Oncology/Haematology, Kantonsspital Graubünden, Chur, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Brunner
authors.forename: Roger
authors.initials: R
authors.lastname: von Moos
authors.forename: Ulrich
authors.initials: U
authors.lastname: Mey
authors.forename: Ulrike
authors.initials: U
authors.lastname: Camenisch Gross
authors.forename: Tobias
authors.initials: T
authors.lastname: Freyholdt
authors.forename: Richard
authors.initials: R
authors.lastname: Cathomas
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D000069287:Capecitabine; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000188:drug therapy* / Q000235:genetics*; D004252:DNA Mutational Analysis; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000031:analogs & derivatives; D006801:Humans; D000077146:Irinotecan; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D012189:Retrospective Studies; D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D009944:Organoplatinum Compounds; D011518:Proto-Oncogene Proteins; D000077150:Oxaliplatin; D003841:Deoxycytidine; D000069287:Capecitabine; D000077146:Irinotecan; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins; D005472:Fluorouracil; D002166:Camptothecin