title: A retrospective comparison of three sequential groups of patients with Recurrent/Refractory chronic lymphocytic leukemia treated with fludarabine-based regimens.
abstract: BACKGROUND
  Combining therapeutics with single-agent activity has improved treatment for patients with many malignancies. Debate continues about the impact of treatment on survival in patients with chronic lymphocytic leukemia (CLL). Purine analogues are the most active agents for treatment of patients with CLL. Recently, it was shown that a chemoimmunotherapy regimen combining fludarabine (F), cyclophosphamide (C), and rituximab (R) (FCR) was very effective in treating patients with recurrent and/or refractory CLL. The objective of the current analysis was to determine whether improvements in treatment have had an impact on survival for patients with CLL.
  
  
  METHODS
  Three nonoverlapping, sequential groups of patients enrolled on Phase II studies who received treatment with F (n = 251 patients), FC (n = 111 patients), or FCR (n = 143 patients) were analyzed. Pretreatment characteristics, responses to treatment, and overall survival were compared.
  
  
  RESULTS
  Patients who were treated with FCR had a higher complete remission rate compared with patients who were treated with combined F and C or with F alone. Statistically significantly longer estimated median survival was noted for patients who received FCR. A Cox proportional hazards, multivariable model for overall survival that included all patients (n = 505) showed that patients who received FCR had longer survival (P < 0.0001) after adjusting for other significant (P < 0.05) pretreatment characteristics, including age, hemoglobin, beta-2 microglobulin, and the number of prior treatments.
  
  
  CONCLUSIONS
  The results of this retrospective comparison of patients with recurrent and refractory CLL indicated a higher complete remission rate and the longest estimated survival for patients who were treated with FCR, providing the basis for randomized clinical trials of this regimen.
authors.affiliation: Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA. wwierda@mdanderson.org
authors.forename: William
authors.initials: W
authors.lastname: Wierda
authors.forename: Susan
authors.initials: S
authors.lastname: O'brien
authors.forename: Stefan
authors.initials: S
authors.lastname: Faderl
authors.forename: Alessandra
authors.initials: A
authors.lastname: Ferrajoli
authors.forename: Xuemei
authors.initials: X
authors.lastname: Wang
authors.forename: Kim-Anh
authors.initials: KA
authors.lastname: Do
authors.forename: Guillermo
authors.initials: G
authors.lastname: Garcia-Manero
authors.forename: Deborah
authors.initials: D
authors.lastname: Thomas
authors.forename: Jorge
authors.initials: J
authors.lastname: Cortes
authors.forename: Farhad
authors.initials: F
authors.lastname: Ravandi-Kashani
authors.forename: Francis
authors.initials: F
authors.lastname: Giles
authors.forename: Susan
authors.initials: S
authors.lastname: Lerner
authors.forename: Hagop
authors.initials: H
authors.lastname: Kantarjian
authors.forename: Michael
authors.initials: M
authors.lastname: Keating
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects; D017322:Clinical Trials, Phase II as Topic; D003520:Cyclophosphamide / Q000627:therapeutic use*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000188:drug therapy* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012189:Retrospective Studies; D000069283:Rituximab; D016896:Treatment Outcome; D014740:Vidarabine / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D000970:Antineoplastic Agents; D000069283:Rituximab; D003520:Cyclophosphamide; D014740:Vidarabine; C024352:fludarabine