MYELOPROLIFERATIVE NEOPLASMS WHO 2016 Chronic myeloid leukemia, BCR-ABL 1 positive Chronic neutrophilic leukemia Polycythaemia vera Primary myelofibrosis Essential thrombocythaemia Chronic eosinophilic leukaemia, NOS Chronic neutrophilic leukemia, NOS Myeloproliferative neoplasm, unclassifiable
Chronic myeloid leukemia (CML) lat. Myelosis chronica CHRONIC myelogenous leukemia (CML) is a malignant hematological disorder of the human hematopoietic stem cells CML arises from a pluripotent hematopoietic stem cell that has undergone a reciprocal translocation between the BCR gene on chromosome 22 and the ABL proto-oncogene on chromosome 9 Fusion gene BCR-ABL has been found detected in all myeloid lineages, in B lymphocytes and some other lymphoid cells
Pathogenesis CML was the first cancer demonstrated to have underlying genetic abnormality. It was discovered in 1960 in Philadelphia by Peter Nowell and David Hungerford – chromosome Philadelphia.
t(9;22)(q34;q11) is responsible for the oncogenic BCR-ABL gene fusion, located on the shorter derivative 22 chromosome. This gene encodes the continuously activated BCR-ABL fusion protein Protein products (transcripts of BCR-ABL oncogene) formed during the transcription process can have different isoforms, depending on the precise location of the fusion: p190 – usually associated with ALL -p210 – associated with CML (and sometimes with ALL) p230 – associated with CNL, trombocytosis FISH
BCR-ABL has tyrosine-kinase activity and participates in intracellular signal transduction. Activity imparts growth advantage to leukemic cells: Increased proliferation and cytokine-independent growth Inhibition of apoptosis Alteration of adhesion pathways
Epidemiology of CML CML accounts for 15 to 20 percent of all adult leukemias. M > F (1.3: 1) The incidence in adults is 1-2 cases per 100,000 population per year,, median age at diagnosis is 55-60 years. CML is rare in persons aged < 19 years (1-2 cases per million population) Leukemogens - Exposure to very high doses of ionizing radiation can increase the occurrence of CML above the expected frequency in comparable populations (e.g. Hiroshima & Nagasaki, Chernobyl); the other etiologic agents are actually not to be known.
Clinical presentation of CML
Chronic phase Majority – above 80% - of cases diagnosed in the chronic phase of CML, the disease is sometimes recognized incidentally Clinical onset of chronic phase may by insidious 70% of patients who are symptomatic may present with easy fatigability, loss of sense of well-being, decreased tolerance to exertion, anorexia, abdominal discomfort, early satiety and left upper quadrant pain or mass (related to hepatosplenomegaly), weight loss, and excessive sweating. Physical examination: hepatomegaly splenomegaly paleness Remember that some patient may present with leukostasis!
Laboratory results WBC > 20 000/μl (often > 100000/μl), Increased granulocytes of all types, typically including mature myeloid cells Neutrophil hypersegmentation Increased number of basophils decreased Hb concentration (sometimes) platelet count normal or increased
Myeloid maturation MATURATION myeloblast promyelocyte myelocyte metamyelocyte band neutrophil MATURATION Adapted and modified from U Va website
Leukostasis accumulation of blasts in microcirculation with impaired perfusion lungs: hypoxemia, pulmonary infiltrates CNS: stroke, loss of consciousness headache, vision disorders sometimes priapism seen with WBC >> 100 x 109/L, esp. when WBC > 200-3009/L (10% patients)
Diagnosis: Whole blood count + peripheral blood smear evaluation BM smear evaluation and trephine biopsy Special stains – cytochemistry Classic cytogenetics – to look for t(9;22) translocation FISH – to show the presence of BCR-ABL fusion gene Molecular investigations – RT-PCR, RQ-PCR – to detect transcript of BCR-ABL oncogene (p190, p210, p230) and to evalute response to the treatment (molecular response)
Peripheral blood
Bone marrow
BCR/ABL dual fusion t(9;22)(q34;q11) RRGG Normal signal pattern BCR/ABL dual fusion t(9;22)(q34;q11) 9 der(9) 22 der(22) ABL 9q34 BCR 22q11 FFRG Typical abnormal FISH Fluorescent In Situ Hybridisation
Philadelphia chromosome and/or BCR-ABL detection CML diagnosis Philadelphia chromosome and/or BCR-ABL detection
The presence of Ph+/BCR-ABL1+ cells CML biology before IFN/TKI era „health” Diagnosis Disease App 6 yrs 3-4 yrs 3-12 m app 20 m Chronic phase advanced disease WBC 10 000/ul WBC 100 000/ul Death The presence of Ph+/BCR-ABL1+ cells
CML- early and advanced phases Chronic phase Accelerated phase 10–19% myeloblasts in the blood or bone marrow smear - >20% basophils in the blood or bone marrow - Platelet count <100,000, unrelated to therapy - Platelet count >1,000,000, unresponsive to therapy - Cytogenetic evolution with new abnormalities in addition to the Philadelphia chromosome Increasing splenomegaly or white blood cell count, unresponsive to therapy Blast crisis - >20% myeloblasts or lymphoblasts in the blood or bone marrow smear - large clusters of blasts in the bone marrow on biopsy Development of a chloroma (solid focus of leukemia outside the bone marrow), or another extramedullary presentation
Principles of treatment Tyrosine Kinase Inhibitors: imatinib – the first generation of TKI dasatinib, nilotinib– the second generation of TKI bosutinib, ponatinib Interferon alfa 2b- in specific clinical situations Alkylating agents – Ara-C, Hydroxyurea and steroids in the past, in rare situation nowadays Allogeneic HSCT
The aim of the treatment Complete hematologic remission (CHR) Cytogenetic response Molecular response Leukemia-free survival The cure Hochhaus, Venice 2006
Therapy- history and present Hydroxyurea, busulfan- cytoreductive treatment (1946-1975) no ifluence on overall survival, no cytogenetic response, leukocyte count reduction, decresed of splenomegaly, hematologic response, better qauality of life AlloHSCT (1979/1981) Cure of 50-60% of patients Interferon alfa (1982) Complete hematologic response (CHR ) 50-80%, major cytogentic response 30%, complete cytogenetic response in up to 10% of patients Imatinib- first TKI (1998) CHR 95%, major cytogenetic response 85%, including complete CyR 75% TKI - second generation: (2004- ) Dasatinib Nilotinib Ponatinib Bosutinib
Imatinib
Imatinib Chronic phase 400 mg Accelerated phase/blast crisis 600/800 mg with/wo chemtherapy
Event free survival patients treated with IM (IRIS study)
Monitoring: every 3 months untill CCyR Cytogenetic response Definition: Complete CCyR: Ph+ 0% Partial PCyR: Ph+ 1%-35% Minor (MCyR: Ph+ 36%-65% Minimal: Ph+ 66%-95% Lack of response : Ph+ >95% Monitoring: every 3 months untill CCyR
Molecular response Definition: Deep (MolR): transcript BCR-ABL undetectable Major (MMolR): BCR-ABL ≤ 0.1% Monitoring: every 3 months
Response to TKI Optimal Failure 3 months CHR BCR-ABL 10% Ph 35% No CHR Ph > 95% 6 months BCR-ABL 1% Ph 0% BCR-ABL > 10% Ph > 35% 12 months BCR-ABL 0.1% BCR-ABL > 1% Ph > 0% CHR- complete hematologic response
First line treatment Imatinib 400 mg/d Dasatinib 100 mg/d Nilotinib 2x 300 mg/d
Second line treatment TKI switch Intolerance of first line treatment Failure after 3-5 months of first line treatment T315I mutation- ponatinib AlloHSCT Blast crisis Should be considered after failure of first line treatment, recommended after failure of second line treatment Treatment failure in patients with T351I mutation
Allogeneic HSCT The only (?) curative method of treatment Leukemia free survival > 60-70% of patients Treatment related mortality 10-15% Relapse rate 20% Relapse treatment Donor lymphocyte infusion TKI
Survival after HLA Matched Sibling HCT for CML, 2005-2015 Slide 31: Allogeneic transplants for CML are currently reserved for patients where tyrosine kinase inhibitors have failed or are poorly tolerated. The CIBMTR has data for 2,015 HLA-matched sibling donor transplants for CML from 2005 to 2015. Three-year probabilities of survival were 66% ± 1%, 51% ± 4% and 29% ± 4% for patients in chronic phase, in accelerated phase and blast phase; respectively.
Chronic graft versus host disease
Overview CML registry data 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 number of allografts 1361 1028 990 819 758 644 564 386 241 260 RIC 136 132 162 187 194 159 107 56 number of autografts 143 66 44 28 15 13 6 4 Related donors unrelated donors 842 508 674 345 610 372 464 351 432 318 352 282 306 252 175 206 134 status at alloTx: CP1 CP2 AP BC 996 90 121 61 690 99 81 627 131 125 51 444 124 54 448 111 92 45 390 82 68 85 71 49 163 72 53 40 88 62 21 38 age > 50 years 262 183 180 152 178 105 108 73
Selected Disease Trends for Allogeneic HCT in the US Slide 14: This slide represents trends in the utility of allogeneic transplants for various indications and shows that allogeneic transplant activity is decreasing in lymphomas and CLL highlighting the availability of non-transplant therapeutic options.
OS in IRIS study- Imatinib 400mg OS after alloHSCT OS in IRIS study- Imatinib 400mg