title: Phase I/II trial of irinotecan and S-1 combination chemotherapy as a second-line treatment for advanced colorectal cancer.
abstract: BACKGROUND
  This study attempted to determine the therapeutic dosage of irinotecan and S-1 (IRIS) as a second-line treatment for colorectal cancer (CRC).
  
  
  METHODS
  S-1 was administered on days 1-14 of a 28-day cycle. Irinotecan was administered on days 1 and 15. The irinotecan dose was then escalated to determine the maximum-tolerated dose and the recommended dose at a fixed dosage of S-1 (80 or 65 mg·m(-2)·day(-1)). The S-1 dose was reduced to 65 mg·m(-2)·day(-1) when dose-limiting toxicities were observed at 80 mg·m(-2)· day(-1) and the irinotecan dose was increased.
  
  
  RESULTS
  The recommended dose was 65 mg/m(2) for S-1 and 75 mg/m(2) for irinotecan. Twenty-one patients were treated at the recommended dose. The overall response rate was 28.6%.
  
  
  CONCLUSIONS
  This modified IRIS regimen is considered effective with acceptable toxicities for advanced CRC resistant to treatment with 5-fluorouracil/leucovorin or uracil and tegafur/leucovorin.
authors.affiliation: Niigata Cancer Center Hospital, Niigata, Japan.
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Takii
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Yamazaki
authors.forename: Takayuki
authors.initials: T
authors.lastname: Okada
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Tani
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Funakoshi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Maruyama
authors.forename: Jun
authors.initials: J
authors.lastname: Hasegawa
authors.forename: Kouhei
authors.initials: K
authors.lastname: Akazawa
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Hatakeyama
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D000077146:Irinotecan; D008297:Male; D020714:Maximum Tolerated Dose; D008875:Middle Aged; D010094:Oxonic Acid / Q000008:administration & dosage; D005641:Tegafur / Q000008:administration & dosage; D016896:Treatment Outcome
chemical_list: D004338:Drug Combinations; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid; D000077146:Irinotecan; D002166:Camptothecin