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British Journal of Haematology Dec 2022Despite the success of BCR-ABL-specific tyrosine kinase inhibitors (TKIs) such as imatinib in chronic phase (CP) chronic myeloid leukaemia (CML), patients with blast... (Review)
Review
Despite the success of BCR-ABL-specific tyrosine kinase inhibitors (TKIs) such as imatinib in chronic phase (CP) chronic myeloid leukaemia (CML), patients with blast phase (BP)-CML continue to have a dismal outcome with median survival of less than one year from diagnosis. Thus BP-CML remains a critical unmet clinical need in the management of CML. Our understanding of the biology of BP-CML continues to grow; genomic instability leads to acquisition of mutations which drive leukaemic progenitor cells to develop self-renewal properties, resulting in differentiation block and a poor-prognosis acute leukaemia which may be myeloid, lymphoid or bi-phenotypic. Similar advances in therapy are urgently needed to improve patient outcomes; however, this is challenging given the rarity and heterogeneity of BP-CML, leading to difficulty in designing and recruiting to prospective clinical trials. This review will explore the treatment of BP-CML, evaluating the data for TKI therapy alone, combinations with intensive chemotherapy, the role of allogeneic haemopoietic stem cell transplantation, the use of novel agents and clinical trials, as well as discussing the most appropriate methods for diagnosing BP and assessing response to therapy, and factors predicting outcome.
Topics: Humans; Blast Crisis; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Prospective Studies; Imatinib Mesylate; Protein Kinase Inhibitors
PubMed: 35866251
DOI: 10.1111/bjh.18370 -
Best Practice & Research. Clinical... Jun 2022Myeloproliferative neoplasms (MPN) have an inherent risk of transformation into blast phase (MPN-BP) or accelerated phase (MPN-AP) which is characterized by presence of... (Review)
Review
Myeloproliferative neoplasms (MPN) have an inherent risk of transformation into blast phase (MPN-BP) or accelerated phase (MPN-AP) which is characterized by presence of ≥20% or 10-19% peripheral blood or bone marrow blasts, respectively. Primary myelofibrosis (PMF) is associated with the highest risk of blastic transformation (14.2%), followed by polycythemia vera (PV) (6.8%) and essential thrombocythemia (ET) (3.8%). Risk of leukaemic transformation (LT) in PMF can be determined by a three-tiered model based on presence of IDH1 mutation, circulating blasts ≥3%, SRSF2 mutation, age >70 years, ASXL1 mutation, and moderate/severe anemia with high, intermediate, and low risk groups (LT incidence 57%, 17%, and 8%, respectively). Currently, treatment of MPN-AP/BP includes acute myeloid leukaemia (AML)-like induction chemotherapy or hypomethylating agents alone or in combination with venetoclax and/or ruxolitinib. In transplant-eligible patients, our goal is to achieve complete remission with or without count recovery, before proceeding with allogeneic stem cell transplantation, which is the only modality associated with long-term survival. In the current review, we discuss our diagnostic, prognostic, and therapeutic approach to patients with MPN-AP/BP.
Topics: Humans; Aged; Blast Crisis; Myeloproliferative Disorders; Prognosis; Bone Marrow; Mutation; Leukemia, Myeloid, Acute
PubMed: 36333070
DOI: 10.1016/j.beha.2022.101379 -
Blood Cancer Journal Jul 2023Leukemic transformation in myeloproliferative neoplasms (MPN), also referred to as "blast-phase MPN", is the most feared disease complication, with incidence estimates... (Review)
Review
Leukemic transformation in myeloproliferative neoplasms (MPN), also referred to as "blast-phase MPN", is the most feared disease complication, with incidence estimates of 1-4% for essential thrombocythemia, 3-7% for polycythemia vera, and 9-13% for primary myelofibrosis. Diagnosis of MPN-BP requires the presence of ≥20% circulating or bone marrow blasts; a lower level of excess blasts (10-19%) constitutes "accelerated phase" disease (MPN-AP). Neither "intensive" nor "less intensive" chemotherapy, by itself, secures long-term survival in MPN-BP. Large-scale retrospective series have consistently shown a dismal prognosis in MPN-BP, with 1- and 3-year survival estimates of <20% and <5%, respectively. Allogeneic hematopoietic stem cell transplant (AHSCT) offers the possibility of a >30% 3-year survival rate and should be pursued, ideally, while the patient is still in chronic phase disease. The value of pre-transplant bridging chemotherapy is uncertain in MPN-AP while it is advised in MPN-BP; in this regard, we currently favor combination chemotherapy with venetoclax (Ven) and hypomethylating agent (HMA); response is more likely in the absence of complex/monosomal karyotype and presence of TET2 mutation. Furthermore, in the presence of an IDH mutation, the use of IDH inhibitors, either alone or in combination with Ven-HMA, can be considered. Pre-transplant clearance of excess blasts is desired but not mandated; in this regard, additional salvage chemotherapy is more likely to compromise transplant eligibility rather than improve post-transplant survival. Controlled studies are needed to determine the optimal pre- and post-transplant measures that target transplant-associated morbidity and post-transplant relapse.
Topics: Humans; Blast Crisis; Retrospective Studies; Neoplasm Recurrence, Local; Myeloproliferative Disorders; Polycythemia Vera; Mutation; Chronic Disease
PubMed: 37460550
DOI: 10.1038/s41408-023-00878-8 -
Hematology/oncology Clinics of North... Apr 2021Accelerated and blast phase myeloproliferative neoplasms are advanced stages of the disease with historically a poor prognosis and little improvement in outcomes thus... (Review)
Review
Accelerated and blast phase myeloproliferative neoplasms are advanced stages of the disease with historically a poor prognosis and little improvement in outcomes thus far. The lack of responses to standard treatments likely results from the more aggressive biology reflected by the higher incidence of complex karyotype and high-risk somatic mutations, which are enriched at the time of transformation. Treatment options include induction chemotherapy (7 + 3) as that used on de novo acute myeloid leukemia or hypomethylating agent-based therapy, which has shown similar outcomes. Allogeneic stem cell transplantation remains the only potential for cure.
Topics: Blast Crisis; Hematopoietic Stem Cell Transplantation; Humans; Leukemia, Myeloid, Acute; Mutation; Myeloproliferative Disorders
PubMed: 33641872
DOI: 10.1016/j.hoc.2020.12.008 -
The Lancet. Haematology Jan 2023Ponatinib and blinatumomab are effective therapies in patients with Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukaemia, and their combination...
BACKGROUND
Ponatinib and blinatumomab are effective therapies in patients with Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukaemia, and their combination might be a promising treatment option. In this study, we aimed to evaluate this chemotherapy-free strategy.
METHODS
We did a single-centre, single-arm, phase 2 study at the University of Texas MD Anderson Cancer Center, Houston, TX, USA, in patients aged 18 years or older with newly diagnosed or relapsed or refractory Ph-positive acute lymphoblastic leukaemia or chronic myeloid leukaemia in lymphoid blast phase. Patients with an ECOG performance status of 2 or less who had a total bilirubin concentration two-times the upper limit of normal (ULN) or less (≤2·4 mg/dL), alanine aminotransferase and aspartate aminotransferase concentration no more than three-times the ULN, and serum lipase and amylase concentrations no more than three-times the ULN were eligible for inclusion. Ponatinib 30 mg orally and continuous intravenous blinatumomab 28 μg over 24 h (for 28 days each cycle) were given in combination for up to five 42-day cycles, followed by ponatinib monotherapy. Patients received 12 doses of intrathecal chemotherapy as CNS prophylaxis. The primary endpoints were complete molecular response (defined as absence of a detectable BCR-ABL1 transcript by PCR at a sensitivity of 0·01%) in patients with newly diagnosed disease and overall response in patients with relapsed or refractory disease or chronic myeloid leukaemia in lymphoid blast phase. All assessments were done according to the intention-to-treat principle. The trial completed its original target accrual and was amended on March 23, 2022, to enrol an additional 30 patients, thus increasing the sample size to 90 patients. The trial is registered with ClinicalTrials.gov, NCT03263572, and it is ongoing.
FINDINGS
Between Feb 6, 2018, to May 6, 2022, 60 (83%) of 72 patients assessed were enrolled and received ponatinib and blinatumomab (40 [67%] patients had newly diagnosed Ph-positive acute lymphoblastic leukaemia, 14 [23%] had relapsed or refractory Ph-positive acute lymphoblastic leukaemia, and six [10%] had chronic myeloid leukaemia in lymphoid blast phase). 32 (53%) patients were men and 28 (47%) were women; 51 (85%) patients were White or Hispanic; and the median age of participants was 51 years (IQR 36-68). The median duration of follow-up for the entire cohort was 16 months (IQR 11-24). Of patients with newly diagnosed Ph-positive acute lymphoblastic leukaemia, 33 (87%) of 38 evaluable patients had a complete molecular response. 12 (92%) of 13 evaluable patients with relapsed or refractory Ph-positive acute lymphoblastic leukaemia had an overall response. 11 (79%) had a complete molecular response. Five (83%) of six patients with chronic myeloid leukaemia in lymphoid blast phase had an overall response. Two (33%) had a complete molecular response. The most common grade 3-4 adverse events that occurred in more than 5% of patients were infection (22 [37%] patients), increased amylase or lipase concentration (five [8%] patients), increased alanine aminotransferase or aspartate aminotransferase concentration (four [7%] patients), pain (four [7%] patients), and hypertension (four [7%] patients). One (2%) patient discontinued blinatumomab due to tremor. Three (5%) patients discontinued ponatinib secondary to cerebrovascular ischaemia, portal vein thrombosis, and coronary artery stenosis in one patient each. No treatment-related deaths were observed.
INTERPRETATION
The chemotherapy-free combination of ponatinib and blinatumomab resulted in high rates of complete molecular response in patients with newly diagnosed and relapsed or refractory Ph-positive acute lymphoblastic leukaemia. Patients with newly diagnosed Ph-positive acute lymphoblastic leukaemia could be spared the toxicities associated with chemotherapy and the need for allogeneic haematopoietic stem-cell transplantation in first response.
FUNDING
Takeda Oncology and Amgen.
Topics: Male; Humans; Female; Adult; Middle Aged; Aged; Philadelphia Chromosome; Blast Crisis; Alanine Transaminase; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Antineoplastic Combined Chemotherapy Protocols
PubMed: 36402146
DOI: 10.1016/S2352-3026(22)00319-2 -
International Journal of Molecular... Oct 2022Blast crisis (BC) is one of the most dreaded complications of chronic myeloid leukemia (CML). Fortunately, the incidence of BC has diminished markedly in the tyrosine... (Review)
Review
Blast crisis (BC) is one of the most dreaded complications of chronic myeloid leukemia (CML). Fortunately, the incidence of BC has diminished markedly in the tyrosine kinase inhibitor (TKI) era. The primary objective of initial treatment in BC is to achieve a second chronic phase (CP) and to proceed to an allogeneic stem cell transplantation (SCT) in eligible patients. The clinical outcome of patients with CML BC remains unsatisfactory, even with highly potent TKIs, as remissions are short lived and there is an unmet need for novel therapies. We provide a comprehensive summary reviewing the current management of Lymphoid BC.
Topics: Blast Crisis; Hematopoietic Stem Cell Transplantation; Humans; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Protein Kinase Inhibitors
PubMed: 36233138
DOI: 10.3390/ijms231911836 -
Acta Haematologica 2021Myeloproliferative neoplasms (MPNs) can transform into blast phase MPN (leukemic transformation; MPN-BP), typically via accelerated phase MPN (MPN-AP), in ∼20-25% of... (Review)
Review
BACKGROUND
Myeloproliferative neoplasms (MPNs) can transform into blast phase MPN (leukemic transformation; MPN-BP), typically via accelerated phase MPN (MPN-AP), in ∼20-25% of the cases. MPN-AP and MPN-BP are characterized by 10-19% and ≥20% blasts, respectively. MPN-AP/BP portend a dismal prognosis with no established conventional treatment. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the sole modality associated with long-term survival.
SUMMARY
MPN-AP/BP has a markedly different mutational profile from de novo acute myeloid leukemia (AML). In MPN-AP/BP, TP53 and IDH1/2 are more frequent, whereas FLT3 and DNMT3A are rare. Higher incidence of leukemic transformation has been associated with the most aggressive MPN subtype, myelofibrosis (MF); other risk factors for leukemic transformation include rising blast counts above 3-5%, advanced age, severe anemia, thrombocytopenia, leukocytosis, increasing bone marrow fibrosis, type 1 CALR-unmutated status, lack of driver mutations (negative for JAK2, CALR, or MPL genes), adverse cytogenetics, and acquisition of ≥2 high-molecular risk mutations (ASXL1, EZH2, IDH1/2, SRSF2, and U2AF1Q157). The aforementioned factors have been incorporated in several novel prognostic scoring systems for MF. Currently, elderly/unfit patients with MPN-AP/BP are treated with hypomethylating agents with/without ruxolitinib; these regimens appear to confer comparable benefit to intensive chemotherapy but with lower toxicity. Retrospective studies in patients who acquired actionable mutations during MPN-AP/BP showed positive outcomes with targeted AML treatments, such as IDH1/2 inhibitors, and require further evaluation in clinical trials. Key Messages: Therapy for MPN-AP patients represents an unmet medical need. MF patients, in particular, should be appropriately stratified regarding their prognosis and the risk for transformation. Higher-risk patients should be monitored regularly and treated prior to progression to MPN-BP. MPN-AP patients may be treated with hypomethylating agents alone or in combination with ruxolitinib; also, patients can be provided with the option to enroll in rationally designed clinical trials exploring combination regimens, including novel targeted drugs, with an ultimate goal to transition to transplant.
Topics: Allografts; Blast Crisis; Hematopoietic Stem Cell Transplantation; Humans; Leukemia, Myeloid, Acute; Mutation; Myeloproliferative Disorders; Neoplasm Proteins
PubMed: 33882481
DOI: 10.1159/000512929 -
American Journal of Hematology Apr 2023
Topics: Humans; Blast Crisis; Myeloproliferative Disorders; Hematopoietic Stem Cell Transplantation
PubMed: 36655312
DOI: 10.1002/ajh.26849 -
British Journal of Haematology Oct 2023Management approaches for accelerated and blast phase myeloproliferative neoplasms remain challenging for clinicians and patients alike. Despite many therapeutic... (Review)
Review
Management approaches for accelerated and blast phase myeloproliferative neoplasms remain challenging for clinicians and patients alike. Despite many therapeutic advances, outcomes for those patients who are not allogeneic haematopoietic cell transplant eligible remain, in general, very poor. Estimated survival rates for such blast phase patients is frequently reported as less than 6 months. No specific immunological, genomic or clinicopathological signature currently exists that accurately predicts the risk and timing of transformation, which frequently induces a high degree of anxiety among patients and clinicians alike. Within this review article, we provide an up-to-date summary of current understanding of the underlying pathogenesis of accelerated and blast phase disease and discuss current therapeutic approaches and realistic outcomes. Finally, we discuss how the horizon may look with the introduction of more novel agents into the clinical arena.
Topics: Humans; Blast Crisis; Hematopoietic Stem Cell Transplantation; Mutation; Myeloproliferative Disorders
PubMed: 37527977
DOI: 10.1111/bjh.19010 -
Leukemia Mar 2023Treatment of chronic myeloid leukemia has improved significantly with the introduction of tyrosine kinase inhibitors (TKIs), and treatment guidelines based on numerous... (Review)
Review
Treatment of chronic myeloid leukemia has improved significantly with the introduction of tyrosine kinase inhibitors (TKIs), and treatment guidelines based on numerous clinical trials are available for chronic phase disease. However for CML in the blast phase (CML-BP), prognosis remains poor and treatment options are much more limited. The spectrum of treatment strategies for children and adolescents with CML-BP has largely evolved empirically and includes treatment principles derived from adult CML-BP and pediatric acute leukemia. Given this heterogeneity of treatment approaches, we formed an international panel of pediatric CML experts to develop recommendations for consistent therapy in children and adolescents with this high-risk disease based on the current literature and national standards. Recommendations include detailed information on initial diagnosis and treatment monitoring, differentiation from Philadelphia-positive acute leukemia, subtype-specific selection of induction therapy, and combination with tyrosine kinase inhibitors. Given that allogeneic hematopoietic stem cell transplantation currently remains the primary curative intervention for CML-BP, we also provide recommendations for the timing of transplantation, donor and graft selection, selection of a conditioning regimen and prophylaxis for graft-versus-host disease, post-transplant TKI therapy, and management of molecular relapse. Management according to the treatment recommendations presented here is intended to provide the basis for the design of future prospective clinical trials to improve outcomes for this challenging disease.
Topics: Adult; Humans; Child; Adolescent; Blast Crisis; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Hematopoietic Stem Cell Transplantation; Prognosis; Graft vs Host Disease; Leukemia, Myeloid, Acute
PubMed: 36707619
DOI: 10.1038/s41375-023-01822-2