Blood, 2016-01-21, Vol.127 (3), p.303-309
Accurate identification of patients likely to achieve long-progression-free survival (PFS) after chemoimmunotherapy is essential given the availability of less toxic alternatives, such as ibrutinib. Fludarabine, cyclophosphamide, and rituximab (FCR) achieved a high response rate, but continued relapses were seen in initial reports. We reviewed the original 300 patient phase 2 FCR study to identify long-term disease-free survivors. Minimal residual disease (MRD) was assessed posttreatment by a polymerase chain reaction-based ligase chain reaction assay (sensitivity 0.01%). At the median follow-up of 12.8 years, PFS was 30.9% (median PFS, 6.4 years). The 12.8-year PFS was 53.9% for patients with mutated immunoglobulin heavy chain variable (IGHV) gene (IGHV-M) and 8.7% for patients with unmutated IGHV (IGHV-UM). 50.7% of patients with IGHV-M achieved MRD-negativity posttreatment; of these, PFS was 79.8% at 12.8 years. A plateau was seen on the PFS curve in patients with IGHV-M, with no relapses beyond 10.4 years in 42 patients (total follow-up 105.4 patient-years). On multivariable analysis, IGHV-UM (hazard ratio, 3.37 [2.18-5.21]; P 〈 .001) and del(17p) by conventional karyotyping (hazard ratio, 7.96 [1.02-61.92]; P = .048) were significantly associated with inferior PFS. Fifteen patients with IGHV-M had 4-color MRD flow cytometry (sensitivity 0.01%) performed in peripheral blood, at a median of 12.8 years posttreatment (range, 9.5-14.7). All were MRD-negative. The high rate of very long-term PFS in patients with IGHV-M after FCR argues for the continued use of chemoimmunotherapy in this patient subgroup outside clinical trials; alternative strategies may be preferred in patients with IGHV-UM, to limit long-term toxicity.
•FCR-treated chronic lymphocytic leukemia patients with mutated IGHV gene achieve long-term PFS, with a plateau on the PFS curve.•MRD-negativity posttreatment is highly predictive of long-term PFS, particularly in patients with mutated IGHV gene.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antineoplastic Combined Chemotherapy Protocols - therapeutic use ; Cause of Death ; Clinical Trials and Observations ; Cyclophosphamide - administration & dosage ; Female ; Humans ; Immunoglobulin Heavy Chains - genetics ; Incidence ; Leukemia, Lymphocytic, Chronic, B-Cell - diagnosis ; Leukemia, Lymphocytic, Chronic, B-Cell - drug therapy ; Leukemia, Lymphocytic, Chronic, B-Cell - genetics ; Leukemia, Lymphocytic, Chronic, B-Cell - mortality ; Male ; Middle Aged ; Mutation ; Neoplasm Staging ; Neoplasm, Residual ; Neoplasms, Second Primary - epidemiology ; Neoplasms, Second Primary - etiology ; Neoplasms, Second Primary - mortality ; Prognosis ; Recurrence ; Remission Induction ; Retreatment ; Rituximab - administration & dosage ; Survival Analysis ; Treatment Outcome ; Vidarabine - administration & dosage ; Vidarabine - analogs & derivatives ; Young Adult
Alma/SFX Local Collection
American Society of Hematology
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