title: Validation study of a prognostic classification in patients with metastatic colorectal cancer who received irinotecan-based second-line chemotherapy.
abstract: OBJECTIVE
  Five prognostic factors had been previously identified in patients with metastatic colorectal cancer (MCRC) who received irinotecan-based second-line chemotherapy. Patients were classified into three prognostic groups based on significant differences in median overall survival (OS). This study is conducted to validate this classification in an external validation cohort.
  
  
  METHODS
  This retrospective study included 193 patients of an external validation cohort who received irinotecan-based second-line chemotherapy after first-line oxaliplatin-based chemotherapy, with or without bevacizumab at three institutions.
  
  
  RESULTS
  Three of the five predefined factors (poorly differentiated adenocarcinoma, LDH ≥400 IU/L, progression-free survival of first-line therapy <6 months) remained highly significant in the validation cohort, although two (performance status 2 and peritoneal metastasis) were associated with borderline significance. The distribution of the three prognostic groups (low risk = no factors, intermediate risk = 1 factor, high risk = 2 or more factors) was low risk (n = 68; 35 %), intermediate risk (n = 80; 41 %), and high risk (n = 45; 23 %). The median OS of each group were 19.8, 11.0, and 7.9 months, respectively, with significant differences between groups, as found in the previous cohort.
  
  
  CONCLUSIONS
  The previous prognostic classification of patients with MCRC who received irinotecan-based second-line chemotherapy was validated in another independent cohort. Validation in prospective studies is warranted.
authors.affiliation: Department of Gastrointestinal Oncology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, Chiba 277-8577, Japan. Kouheis0824@yahoo.co.jp
authors.forename: Kohei
authors.initials: K
authors.lastname: Shitara
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yuki
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yamazaki
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Naito
authors.forename: Hiraku
authors.initials: H
authors.lastname: Fukushima
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Komatsu
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Yasui
authors.forename: Toshimi
authors.initials: T
authors.lastname: Takano
authors.forename: Kei
authors.initials: K
authors.lastname: Muro
mesh_terms: D000230:Adenocarcinoma / Q000145:classification* / Q000188:drug therapy / Q000401:mortality / Q000556:secondary; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D000068258:Bevacizumab; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000145:classification* / Q000188:drug therapy / Q000401:mortality / Q000473:pathology; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D005500:Follow-Up Studies; D006801:Humans; D000077146:Irinotecan; D002955:Leucovorin / Q000008:administration & dosage; D008113:Liver Neoplasms / Q000145:classification* / Q000188:drug therapy / Q000401:mortality / Q000556:secondary; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D010534:Peritoneal Neoplasms / Q000145:classification* / Q000188:drug therapy / Q000401:mortality / Q000556:secondary; D011379:Prognosis; D015996:Survival Rate
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D000068258:Bevacizumab; D000077146:Irinotecan; D002955:Leucovorin; D005472:Fluorouracil; D002166:Camptothecin