title: Weekly irinotecan in patients with metastatic colorectal cancer failing 5-fluorouracil-based chemotherapy: efficacy and prognostic factors.
abstract: OBJECTIVE
  We evaluated the efficacy and tolerability of weekly irinotecan as a second-line treatment in patients with colorectal cancer failing 5-fluorouracil-based chemotherapy and searched for predictive and prognostic factors.
  
  
  METHODS
  A total of 36 patients were included. Median age was 53 years (range, 33-72). One treatment cycle consisted of irinotecan, 100 mg/m2 weekly, for 4 weeks followed by a 2-week rest. Gender, age, primary site, number of metastatic sites, histologic subtype, differentiation, pretreatment CEA, CA 19-9 and lactate dehydrogenase levels and marker response to treatment were investigated as predictive factors for response to treatment and as prognostic factors in the overall survival and time to progression of the patients.
  
  
  RESULTS
  A total of 120 cycles (median, 3 cycles) was delivered. An overall 14% objective response rate (1 complete and 4 partial responses) was achieved. The median response duration was 4 months (range, 2-7). Another 36% of the patients had stable disease for a median duration of 4 months (range, 2-8). Median time-to-disease progression was 4 months and overall median survival was 12 months (95% confidence interval, 9-15). Pretreatment serum CA 19-9 level and marker response to two courses of treatment were found to be clinically significant in time to progression and overall survival. Younger age (< or = 45 years) was a poor prognostic factor associated with a shorter time to progression. The major toxicity was grade 3-4 diarrhea, which occurred in 28% of the patients, and treatment was discontinued in 3 (8%) patients due to toxicity. Other hematological and non-hematological toxicities were mild and manageable.
  
  
  CONCLUSIONS
  We concluded that weekly irinotecan at the dose of 100 mg/m2 is an effective and tolerable treatment option, with a 50% disease control rate, for patients with colorectal cancer failing previous 5-fluorouracil-based chemotherapy.
authors.affiliation: Department of Medical Oncology, Institute of Oncology, Hacettepe University, Sihhiye, Ankara, Turkey.
authors.forename: Aziz
authors.initials: A
authors.lastname: Karaoğlu
authors.forename: Suayib
authors.initials: S
authors.lastname: Yalcin
authors.forename: Gülten
authors.initials: G
authors.lastname: Tekuzman
authors.forename: Ayse
authors.initials: A
authors.lastname: Kars
authors.forename: Ismail
authors.initials: I
authors.lastname: Celik
authors.forename: Nilüfer
authors.initials: N
authors.lastname: Güler
authors.forename: Yavuz
authors.initials: Y
authors.lastname: Ozişik
authors.forename: Alev
authors.initials: A
authors.lastname: Türker
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Barişta
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Güllü
mesh_terms: D000328:Adult; D000368:Aged; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage*; D002166:Camptothecin / Q000008:administration & dosage* / Q000009:adverse effects / Q000031:analogs & derivatives*; D002272:Carcinoembryonic Antigen / Q000032:analysis; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000401:mortality; D018450:Disease Progression; D004334:Drug Administration Schedule; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use*; D006801:Humans; D000077146:Irinotecan; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011379:Prognosis
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D002272:Carcinoembryonic Antigen; D000077146:Irinotecan; D007770:L-Lactate Dehydrogenase; D005472:Fluorouracil; D002166:Camptothecin