Disease overview
Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm with an incidence of 1‐2 cases per 100 000 adults. It accounts for approximately 15% of newly diagnosed cases of ...leukemia in adults.
Diagnosis
CML is characterized by a balanced genetic translocation, t(9;22)(q34;q11.2), involving a fusion of the Abelson gene (ABL1) from chromosome 9q34 with the breakpoint cluster region (BCR) gene on chromosome 22q11.2. This rearrangement is known as the Philadelphia chromosome. The molecular consequence of this translocation is the generation of a BCR‐ABL1 fusion oncogene, which in turn translates into a BCR‐ABL oncoprotein.
Frontline therapy
Four tyrosine kinase inhibitors (TKIs), imatinib, nilotinib, dasatinib, and bosutinib are approved by the United States Food and Drug Administration for first‐line treatment of newly diagnosed CML in chronic phase (CML‐CP). Clinical trials with second generation TKIs reported significantly deeper and faster responses, but they had no impact on survival prolongation, likely because of the existence of highly effective salvage therapies for patients who have a cytogenetic relapse with frontline TKI.
Salvage Therapy
For CML post failure on frontline therapy, second‐line options include second and third generation TKIs. Although potent and selective, these exhibit unique pharmacological profiles and response patterns relative to different patient and disease characteristics, such as patientsʼ comorbidities, disease stage, and BCR‐ABL1 mutational status. Patients who develop the T315I “gatekeeper” mutation display resistance to all currently available TKIs except ponatinib. Allogeneic stem cell transplantation remains an important therapeutic option for patients with CML‐CP who have failed at least 2 TKIs, and for all patients in advanced phase disease. Even among older patients who have a cytogenetic relapse post failure on all TKIs, they can maintain long‐term survival if they continue on a daily most effective/less toxic TKI, with or without the addition of non‐TKI anti‐CML agents (hydroxyurea, omacetaxine, azacitidine, decitabine, cytarabine, busulfan, others).
Disease overview
Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm with an incidence of 1‐2 cases per 100 000 adults. It accounts for approximately 15% of newly diagnosed cases of ...leukemia in adults.
Diagnosis
CML is characterized by a balanced genetic translocation, t(9;22)(q34;q11.2), involving a fusion of the Abelson gene (ABL1) from chromosome 9q34 with the breakpoint cluster region (BCR) gene on chromosome 22q11.2. This rearrangement is known as the Philadelphia chromosome. The molecular consequence of this translocation is the generation of a BCR‐ABL1 fusion oncogene, which in turn translates into a BCR‐ABL1 oncoprotein.
Frontline therapy: Four tyrosine kinase inhibitors (TKIs), imatinib, nilotinib, dasatinib, and bosutinib are approved by the United States Food and Drug Administration for first‐line treatment of patients with newly diagnosed CML in chronic phase (CML‐CP). Clinical trials with second generation TKIs reported significantly deeper and faster responses; this has not translated into improved long‐term survival, because of the availability of effective salvage therapies.
Salvage therapy: For patients who fail frontline therapy, second‐line options include second and third generation TKIs. Second and third generation TKIs, although potent and selective, exhibit unique pharmacological profiles and response patterns relative to different patient and disease characteristics, such as patients’ comorbidities, disease stage, and BCR‐ABL1 mutational status. Patients who develop the T315I “gatekeeper” mutation display resistance to all currently available TKIs except ponatinib. Allogeneic stem cell transplantation remains an important therapeutic option for patients with CML‐CP who have failed at least 2 TKIs, and for all patients in CML advanced phases.
Disease Overview
Chronic Myeloid Leukemia (CML) is a myeloproliferative neoplasm with an incidence of 1–2 cases per 100 000 adults. It accounts for approximately 15% of newly diagnosed cases of ...leukemia in adults.
Diagnosis
CML is characterized by a balanced genetic translocation, t (9;22) (q34;q11.2), involving a fusion of the Abelson gene (ABL1) from chromosome 9q34 with the breakpoint cluster region (BCR) gene on chromosome 22q11.2. This rearrangement is known as the Philadelphia chromosome. The molecular consequence of this translocation is the generation of a BCR::ABL1 fusion oncogene, which in turn translates into a BCR::ABL1 oncoprotein.
Frontline Therapy
Four tyrosine kinase inhibitors (TKIs), imatinib, dasatinib, bosutinib, and nilotinib are approved by the United States Food and Drug Administration for first‐line treatment of newly diagnosed CML in chronic phase (CML‐CP). Clinical trials with second generation TKIs reported significantly deeper and faster responses but had no impact on survival prolongation, likely because of the availability of effective TKIs salvage therapies for patients who have a cytogenetic relapse with frontline TKI therapy.
Salvage Therapy
For CML post failure on frontline therapy, second‐line options include second and third generation TKIs. Although potent and selective, these TKIs exhibit unique pharmacological profiles and response patterns relative to different patient and disease characteristics, such as patients' comorbidities, disease stage, and BCR::ABL1 mutational status. Patients who develop the T315I “gatekeeper” mutation display resistance to all currently available TKIs except ponatinib, asciminib, and olverembatinib. Allogeneic stem cell transplantation remains an important therapeutic option for patients with CML‐CP and failure (due to resistance) of at least two TKIs, and for all patients in advanced phase disease. Older patients who have a cytogenetic relapse post failure on all TKIs can maintain long‐term survival if they continue a daily most effective/least toxic TKI, with or without the addition of non‐TKI anti‐CML agents (hydroxyurea, omacetaxine, azacitidine, decitabine, cytarabine, busulfan and others).
Imatinib, a selective BCR-ABL1 kinase inhibitor, improved the prognosis for patients with chronic myeloid leukemia (CML). We conducted efficacy and safety analyses on the basis of more than 10 years ...of follow-up in patients with CML who were treated with imatinib as initial therapy.
In this open-label, multicenter trial with crossover design, we randomly assigned patients with newly diagnosed CML in the chronic phase to receive either imatinib or interferon alfa plus cytarabine. Long-term analyses included overall survival, response to treatment, and serious adverse events.
The median follow-up was 10.9 years. Given the high rate of crossover among patients who had been randomly assigned to receive interferon alfa plus cytarabine (65.6%) and the short duration of therapy before crossover in these patients (median, 0.8 years), the current analyses focused on patients who had been randomly assigned to receive imatinib. Among the patients in the imatinib group, the estimated overall survival rate at 10 years was 83.3%. Approximately half the patients (48.3%) who had been randomly assigned to imatinib completed study treatment with imatinib, and 82.8% had a complete cytogenetic response. Serious adverse events that were considered by the investigators to be related to imatinib were uncommon and most frequently occurred during the first year of treatment.
Almost 11 years of follow-up showed that the efficacy of imatinib persisted over time and that long-term administration of imatinib was not associated with unacceptable cumulative or late toxic effects. (Funded by Novartis Pharmaceuticals; IRIS ClinicalTrials.gov numbers, NCT00006343 and NCT00333840 .).
In 1957, Hillestad et al. defined acute promyelocytic leukemia (APL) for the first time in the literature as a distinct type of acute myeloid leukemia (AML) with a "rapid downhill course" ...characterized with a severe bleeding tendency. APL, accounting for 10-15% of the newly diagnosed AML cases, results from a balanced translocation, t(15;17) (q22;q12-21), which leads to the fusion of the promyelocytic leukemia (PML) gene with the retinoic acid receptor alpha (RARA) gene. The PML-RARA fusion oncoprotein induces leukemia by blocking normal myeloid differentiation. Before using anthracyclines in APL therapy in 1973, no effective treatment was available. In the mid-1980s, all-trans retinoic acid (ATRA) monotherapy was used with high response rates, but response durations were short. Later, the development of ATRA, chemotherapy, and arsenic trioxide combinations turned APL into a highly curable malignancy. In this review, we summarize the evolution of APL therapy, focusing on key milestones that led to the standard-of-care APL therapy available today and discuss treatment algorithms and management tips to minimize induction mortality.
Few neoplastic diseases have undergone a transformation in a relatively short period like chronic myeloid leukemia (CML) has in the last few years. In 1960, CML was the first cancer in which a unique ...chromosomal abnormality was identified and a pathophysiologic correlation suggested. Landmark work followed, recognizing the underlying translocation between chromosomes 9 and 22 that gave rise to this abnormality and, shortly afterward, the specific genes involved and the pathophysiologic implications of this novel rearrangement. Fast forward a few years and this knowledge has given us the most remarkable example of a specific therapy that targets the dysregulated kinase activity represented by this molecular change. The broad use of tyrosine kinase inhibitors has resulted in an improvement in the overall survival to the point where the life expectancy of patients today is nearly equal to that of the general population. Still, there are challenges and unanswered questions that define the reasons why the progress still escapes many patients, and the details that separate patients from ultimate cure. In this article, we review our current understanding of CML in 2015, present recommendations for optimal management, and discuss the unanswered questions and what could be done to answer them in the near future.
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