ABSTRACT
OBJECTIVE: To evaluate hematological, cytogenetic and molecular responses as well as the overall, progression-free and event-free survivals of chronic myeloid leukemia patients treated with a third tyrosine kinase inhibitor after failing to respond to imatinib and nilotinib/dasatinib. METHODS: Bone marrow karyotyping and real-time quantitative polymerase chain reaction were performed at baseline and at 3, 6, 12 and 18 months after the initiation of treatment with a third tyrosine kinase inhibitor. Hematologic, cytogenetic and molecular responses were defined according to the European LeukemiaNet recommendations. BCR-ABL1 mutations were analyzed by Sanger sequencing. RESULTS: We evaluated 25 chronic myeloid leukemia patients who had been previously treated with imatinib and a second tyrosine kinase inhibitor. Nine patients were switched to dasatinib, and 16 patients were switched to nilotinib as a third-line therapy. Of the chronic phase patients (n=18), 89% achieved a complete hematologic response, 13% achieved a complete cytogenetic response and 24% achieved a major molecular response. The following BCR-ABL1 mutations were detected in 6/14 (43%) chronic phase patients: E255V, Y253H, M244V, F317L (2) and F359V. M351T mutation was found in one patient in the accelerated phase of the disease. The five-year overall, progression-free and event-free survivals were 86, 54 and 22% (p<0.0001), respectively, for chronic phase patients and 66%, 66% and 0% (p<0.0001), respectively, for accelerated phase patients. All blast crisis patients died within 6 months of treatment. Fifty-six percent of the chronic phase patients lost their hematologic response within a median of 23 months. CONCLUSIONS: Although the responses achieved by the third tyrosine kinase inhibitor were not sustainable, a third tyrosine kinase inhibitor may be an option for improving patient status until a donor becomes available for transplant. Because the long-term outcome ...
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Antineoplastic Agents/therapeutic use , Dasatinib/therapeutic use , Drug Resistance/drug effects , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Protein Kinase Inhibitors/therapeutic use , Protein-Tyrosine Kinases/antagonists & inhibitors , Pyrimidines/therapeutic use , Bone Marrow Examination , Disease-Free Survival , Fusion Proteins, bcr-abl/genetics , Kaplan-Meier Estimate , Karyotyping , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Mutation , Real-Time Polymerase Chain Reaction , Time Factors , Treatment OutcomeABSTRACT
OBJECTIVE: To evaluate the use of high-dose sequential chemotherapy in a Brazilian population. METHODS: High-dose cyclophosphamide followed by autologous hematopoietic stem cell transplantation is an effective and feasible therapy for refractory/relapsed lymphomas; this regimen has never before been evaluated in a Brazilian population. All patients (106 with high-grade non-Hodgkin lymphoma and 77 with Hodgkin's lymphoma) submitted to this treatment between 1998 and 2006 were analyzed. Chemotherapy consisted of the sequential administration of high-dose cyclophosphamide (4 or 7 g/m²) and granulocyte-colony stimulating factor (300 µg/day), followed by peripheral blood progenitor cell harvesting, administration of etoposide (2g/m²) and methotrexate (8 g/m² only for Hodgkin's lymphoma) and autologous hematopoietic stem cell transplantation. RESULTS: At diagnosis, non-Hodgkin lymphoma patients had a median age of 45 (range: 8-65) years old, 78 percent had diffuse large B-cell lymphoma and 83 percent had stage III/IV disease. The Hodgkin's lymphoma patients had a median age of 23 (range: 7-68) years old, 64.9 percent had the nodular sclerosis subtype and 65 percent had stage III/IV disease. Nine Hodgkin's lymphoma patients (13 percent) and 10 (9 percent) non-Hodgkin lymphoma patients had some kind of cardiac toxicity. The overall survival, disease-free survival and progression-free survival in Hodgkin's lymphoma were 29 percent, 59 percent and 26 percent, respectively. In non-Hodgkin lymphoma, these values were 40 percent, 49 percent and 31 percent, respectively. High-dose cyclophosphamide-related mortality was 10 percent for Hodgkin's lymphoma and 5 percent for non-Hodgkin lymphoma patients. High-dose cyclophosphamide dosing had no impact on toxicity or survival for both groups. CONCLUSIONS: Despite a greater prevalence of poor prognostic factors, our results are comparable to the literature. The incidence of secondary neoplasias is noteworthy. ...