title: Comparison between patients with Philadelphia-positive chronic phase chronic myeloid leukemia who obtained a complete cytogenetic response within 1 year of imatinib therapy and those who achieved such a response after 12 months of treatment.
abstract: OBJECTIVE
  Imatinib mesylate is a potent inhibitor of BCR-ABL, the constitutively active tyrosine kinase protein critical for the pathogenesis of chronic myeloid leukemia.
  
  
  METHODS
  We reviewed 284 patients with late chronic-phase Philadelphia chromosome (Ph) -positive chronic myeloid leukemia treated with imatinib 400 mg daily after interferon-alpha failure. In a retrospective study, we evaluated the pattern and rapidity of the response to imatinib, comparing the cytogenetic and molecular responses, progression-free and overall survival rates in patients who obtained a complete cytogenetic response within 1 year of treatment (early responders), and in patients where a complete cytogenetic response was detected after 12 months (late responders).
  
  
  RESULTS
  After 3 or 4 years of treatment, the molecular response of the late cytogenetic responders was similar to that of the early cytogenetic responders. At 36 months of treatment the amount of residual disease measured by standardized quantitative reverse-transcriptase polymerase chain reaction was 0.00047 in late responders versus 0.00022 in early responders, and at 48 months it was 0.00019 versus 0.00026 (median values, P value = nonsignificant). The estimated 4-year progression-free survival rate was 88% for early responders and 100% for late responders, while the estimated 4-year overall survival rates were 92% and 100% for early and late responders, respectively.
  
  
  CONCLUSIONS
  The sensitivity and the response (cytogenic and molecular) to imatinib may require 1 year or more. Long-term follow-up results continue to improve in terms of rates and durability of the complete cytogenetic response, major or complete molecular response, and progression-free and overall survival.
authors.affiliation: Institute of Hematology and Medical Oncology "Seràgnoli", University of Bologna, Bologna, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Iacobucci
authors.forename: Gianantonio
authors.initials: G
authors.lastname: Rosti
authors.forename: Marilina
authors.initials: M
authors.lastname: Amabile
authors.forename: Angela
authors.initials: A
authors.lastname: Poerio
authors.forename: Simona
authors.initials: S
authors.lastname: Soverini
authors.forename: Daniela
authors.initials: D
authors.lastname: Cilloni
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Testoni
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Abruzzese
authors.forename: Enrico
authors.initials: E
authors.lastname: Montefusco
authors.forename: Emanuela
authors.initials: E
authors.lastname: Ottaviani
authors.forename: Francesco
authors.initials: F
authors.lastname: Iuliano
authors.forename: Domenico
authors.initials: D
authors.lastname: Russo
authors.forename: Marco
authors.initials: M
authors.lastname: Gobbi
authors.forename: Giuliana
authors.initials: G
authors.lastname: Alimena
authors.forename: Bruno
authors.initials: B
authors.lastname: Martino
authors.forename: Carolina
authors.initials: C
authors.lastname: Terragna
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Pane
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Saglio
authors.forename: Michele
authors.initials: M
authors.lastname: Baccarani
authors.forename: Giovanni
authors.initials: G
authors.lastname: Martinelli
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001549:Benzamides; D018572:Disease-Free Survival; D005260:Female; D016044:Fusion Proteins, bcr-abl / Q000037:antagonists & inhibitors; D006801:Humans; D000068877:Imatinib Mesylate; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy*; D015466:Leukemia, Myeloid, Chronic-Phase / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000008:administration & dosage / Q000627:therapeutic use*; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D011743:Pyrimidines / Q000008:administration & dosage / Q000627:therapeutic use*; D012189:Retrospective Studies; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl