mds/mpn

myelodysplastic / Myeloproliferative neoplasms (MDS/MPN):

myelodysplastic / Myeloproliferative neoplasms ( MDS/MPN) Dr. lobna kamel , m . d Clinical pathology-hematology

Revised WHO Classification ( 2008) of myeloid neoplasms:

Revised WHO Classification ( 2008) of myeloid neoplasms MPN Myeloid/Lymphoid Neoplasms ass . with eosinophilia & other. MDS / MPN MDS AML

MDS/MPN:

MDS/MPN Chronic myelomonocytic leukaemia(CMML) Atypical chronic myeloid leukaemia, BCR-ABL1 negative (a CML) Juvenile myelomonocytic leukaemia (JMML) Myelodysplastic/ Myeloproliferative neoplasms unclassifiable (MDS/MPN-UC) , Provisional entity : refractory anemia with ring sideroblasts and thrombocytosis (RARS-T)

MDS/MPN:

MDS/MPN They uncommon blood cancers that have features of two other types of blood cancers Clonal myeloid disorders that possess both dysplastic& proliferative features The etiology of MDS/ MPN is not known. The incidence of MDS/MPN varies widely, ranging from approximately 3 per 100,000 individuals older than 60 years annually for CMML to as few as 0.13 per 100,000 children from birth to 14 years annually for JMML

MDS/MPN:

MDS/MPN Reliable data concerning the incidence of a CML, are not available. The incidence of MDS/MPN-UC is unknown. The MDS/MPN category was introduced revised (WHO 2008) to include myeloid neoplasms with clinical, laboratory, and morphologic features that overlap MDS and MPN

MDS/MPN:

MDS/MPN Clinical symptoms are caused by complications resulting from cytopenia(s), dysplastic cells , leukemic infiltration of various organ systems, and general constitutional symptoms, such as fever and malaise Patients with MDS/MPD do not have a Ph’ chr or BCR/ABL fusion gene. No specific genetic defects have been identified , though abnormalities in regulation of the ras pathway of signaling proteins appears to be a common finding in CMML, aCML& JMML and may have some role in the abnormal myeloid proliferation associated with these diseases.

Chronic myelomonocytic leukaemia (CMML):

Chronic myelomonocytic leukaemia (CMML) (CMML) has dysplastic and proliferative features. The median age of patients with CMML is 65 to75ys . The median survival is approximately 2 years. CMML is a male-predominant disorder (M:F 2:1)

CMML -Types:

CMML -Types Tow types CMML-1 and CMML-2 The distinction based on the percentage of blasts plus promonocytes in the PB and BM CMML1 = < 5% blasts plus promonocytes in the PB & < 10% blasts plus promonocytes in the BM; CMML2 = > 5% PB blasts plus promonocytes or > 10% or more BM blasts plus promonocytes)

CMML -Diagnosis:

CMML -Diagnosis Common S&S include : fatigue ,weight loss, 50% of patients have splenomegaly, and hepatomegaly. Patients with high monocyte counts may develop a maculopapular skin infiltrate or monocytic pleural or pericardial effusions. Mild anaemia

CMML - Diagnosis:

CMML - Diagnosis 1) Persistent peripheral blood monocytosis (> 1 × 10 9 /L), 2) No Philadelphia chr (Ph’ chr) or BCR/ABL fusion gene, 3) Less than 20% blasts in the blood or bone marrow. 4) Evidence of dysplasia in one or more myeloid lineages

CMML - Diagnosis:

CMML - Diagnosis Anaemia and thrombocytopenia are common and The WBC may vary from N to > 80 × 10 9 /L ( neutrophilia) Monocytes may have normal morphology or may have agranular cytoplasm and/or abnormal nuclear lobation. BM is usually hypercellular and typical trilineage dysplastic features are found in over 80% of cases.

CMML - Diagnosis:

CMML - Diagnosis Cytochemical studies may aid the distinction between monocyte and granulocyte precursors. Cytogenetic abnormalities are found in 30–40% of cases and are not specific for CMML. Deletions of 5q are rare. The incidence of RAS mutations is higher than in other forms of myelodysplasia and is found in up to 40% of cases. Absence of the Philadelphia (ph’) chromosome or the BCR-ABL Gene

CMML - Diagnosis:

CMML - Diagnosis Cytogenetic abnormalities are found in 20% to 40% of patients , but there are no consistently recurring translocations . Activating point mutations in the RAS oncogene appear to occur more often in CMML than in other MDS and MPD categories . t(5;12)(q31;p12) occurs at most in only 1% to 2% of CMML cases 8p11 or the platelet derived factor gene t(1;5)(q23;q33) . Monosomy 7 and trisomy 8 the most common chromosomal abnormalities

CMML - Prognosis:

CMML - Prognosis Patients with CMML have an overall median survival of about 12 months, but the presentation and clinical course can be very heterogeneous The presence of immature myeloid cells in the peripheral blood is the strongest variable determining shorter survival . Anaemia, Thrombocytopenia, Lymphocytosis, a raised serum LDH and an increased percentage of BM blasts .

Atypical chronic myeloid leukaemia (a CML):

Atypical chronic myeloid leukaemia (a CML) It is a poorly defined entity ch. ch by a leucocytosis, >10% circulating immature myeloid cells that are rarely more than 5% blasts, prominent dysgranulopoiesis. It is a subset that characterized by neutrophils and myeloid precursors with pronounced clumping of nuclear chromatin

Atypical chronic myeloid leukaemia (a CML):

Atypical chronic myeloid leukaemia (a CML) Most patients present e’anaemia &/or thrombocytopenia Splenomegaly is common. Eighty per cent of cases have a cytogenetic abnormality but, as with CMML, none is specific for a CML. The prognosis is poorer than for CMML with a median survival of < 20 months. The response to intensive chemotherapy is generally poor

Slide 17:

a CML CMML CML ++ + <10% except in transformation Dysplasia + + Absolute monocytosis < 3% Monocytosis > 15% < 15% Myelocyte peak Immature granulocytes ± – + Basophilia No No Yes BCR–ABL rearrangement ± Ph chromosome ? 40% No RAS mutations

Juvenile Myelomonocytic Leukemia (JMML):

Juvenile Myelomonocytic Leukemia (JMML) It is a disorder with both MD and MP features. The incidence is 1.2 per million per year and the median age at presentation is 1.8 years. 95% of cases occur in children under 5 years old. The condition is twice as common in boys. The incidence of JMML is increased in children with neurofibromatosis type1(NF-1) and with Noonan’s syndrome

Juvenile Myelomonocytic Leukemia (JMML):

Juvenile Myelomonocytic Leukemia (JMML) JMML occurs almost exclusively in children aged 6 ys or younger 1.5 percent of childhood leukemia cases. characterized by moderate leukocytosis with monocytosis, anemia, thrombocytopenia, marked hepatosplenomegaly, and elevated fetal hemoglobin (Hb F)

JMML-Pathogenesis:

JMML -Pathogenesis Disturbed or dysregulated signal transduction through the Ras pathway This disruption of the Ras pathway leads to a very characteristic selective hypersensitivity to , granulocyte-macrophage colony-stimulating factor (GM-CSF). Responsiveness to G-CSF and to IL-3 is normal .

JMML -Clinical features:

JMML - Clinical features Suggestive clinical features Hepatosplenomegaly Lymphadenopathy Pallor Skin rash

JMML-Laboratory features :

JMML- Laboratory features Essential No BCR–ABL fusion gene . Monocytes > 1 × 10 9 /L Marrow blasts < 20% Plus at least two of the following Increased Hb F Circulating myeloid precursors WBC > 10 × 10 9 /L Clonal cytogenetic abnormality Hypersensitivity of myeloid precursors to GM-CSF

JMML-Laboratory features :

JMML- Laboratory features Bone marrow is hypercellular and dysplastic features are often minimal. Chromosomal abnormalities Approximately 30% of patients have monosomy7, Mutations of RAS family of genes – 25% of patients 10% have other chromosomal abnormalities Normal chromosome analysis in 60% of cases.

Slide 24:

Poor Prognostic factors include: age less than 2 years, low platelet count, elevated Hb F levels It is variable, With survival ranging from 5 months to 4 years without treatment. Blast transformation occurs in10–20% of cases, and most patients die from organ failure, especially respiratory failure, due to leukaemic infiltration The relapse rate following HSC transplantation approaches 50% in some series. JMML- Prognosis

Refractory Anemia With Ring Sideroblasts And Thrombocytosis (RARS-T) :

Refractory Anemia With Ring Sideroblasts And Thrombocytosis (RARS-T) It’s classified as MDS/MPN as have combined features: JAK2 & Thrombocytosis---  MPN R ing sideroblasts + poor colony formation with lack of endogenous growth--  MDS

RARS-T:

RARS-T Remains as a "provisional entity" classified as MDS/MPN, unclassifiable, RARS-T. The criteria have been modified to include: RA, dyserythropoiesis in the bone marrow with ring sideroblasts accounting for 15% or more of erythroid precursors, MK with features resembling those in PMF or ET; Platelet threshold is lowered to 450 x 10 9 /L

Classification of pediatric MDS :

Classification of pediatric MDS Juvenile myelomonocytic leukaemia (JMML) Down’s syndrome (DS) Transient abnormal myelopoiesis (TAM) Myeloid leukaemia of DS Myelodysplastic syndrome (MDS) Refractory cytopenia (RC) Refractory anaemia with excess blasts (RAEB)

Myeloproliferative Neoplasms MPN:

Myeloproliferative Neoplasms MPN Chronic myelogenous leukemia, BCR-ABL1 positive Chronic neutrophilic leukemia(CNL) Polycythemia Vera (PV) Primary myelofibrosis essential thrombocythemia Chronic eosinophilic leukemia, not otherwise specified Mastocytosis Myeloproliferative neoplasms, unclassifiable

Chronic myeloid leukaemia (CML):

Chronic myeloid leukaemia (CML) It is a clonal disease that results from an acquired genetic change in a pluripotential haemopoietic stem cell. The incidence of CML appears to be constant worldwide. It occurs in about 1.0–1.5 / 100 000 of the population annually in all countries where statistics are adequate. CML is rare below the age of 20 years but occurs at all decades of life, with a median age of onset of 50–60 years. The incidence is slightly higher in males than in females.

CML - etiology:

CML - etiology Exposure to high doses of irradiation, as occurred in survivors of the atomic bombs exploded in Japan in 1945 No predisposing factors are identifiable . There is no familial predisposition and no definite association with HLA genotypes No causative infectious agent has been implicated

CML –clinical picture:

CML –clinical picture Clinically, CML is a biphasic or triphasic disease Initial ‘chronic’, ‘Indolent’ or ‘Stable’ phase , and Advanced phase (after some years ) Advanced phase can sometimes be subdivided into an earlier accelerated phase and a later acute or blastic phase

CML- Diagnosis:

CML- Diagnosis Patients are usually in the ‘chronic’ phase when CML is diagnosed. This chronic phase lasts typically 2–7 years but it may, in rare cases, last more than 15 or even 20 year. In about 50% of cases the chronic phase transforms unpredictably and abruptly to a more aggressive phase which is named ‘ blastic crisis’ and is now usually described as acute or blastic transformation.

CML- Diagnosis:

CML - Diagnosis In the other half of cases, the disease evolves somewhat more gradually, through an intermediate phase described as ‘accelerated’ phase, which may last for months or years, before frank blastic transformation takes place , which may have myeloblastic or lymphoblastic features. Occasional patients have a disease that progresses gradually to a myelofibrotic or osteomyelosclerotic picture that is characterized by extensive marrow fibrosis.

CML- Diagnosis:

CML - Diagnosis Patients with splenomegaly are usually anaemic , while the Hb level may be normal in patients with ‘early’ disease. WBC at diagnosis is usually in the range of 20–200 × 10 9 /L Some patients may have persistent leucocytosis in the range 10–20 × 10 9 /L Occasional patients may present with leucocyte numbers in the range 200–800 × 10 9 /L . BM: Hypercellular with an increase in M:E (25:1)

CML-Chronic phase:

CML- Chronic phase The blood film shows a full spectrum of cells in the granulocyte series, ranging from blast forms to mature neutrophils, with intermediate myelocytes and neutrophils predominating ( LER) The percentage of blast cells is loosely related to the absolute number of leucocytes, but a value higher than 12% suggests that the patient may already be in acceleration or transformation. eosinophilia and basophilia . Slight absolute lymphocytosis and monocytsis

CML- Diagnosis:

CML- Diagnosis Thrombocytosis > 450 × 10 9 /L but may be normal or even reduced. Occasional nucleated RBCs are present in the circulation in some patients. The NAP is diminished or absent. BCR–ABL fusion gene using (RT-PCR). ABL (9q34) codes for Tyrosine Kinase Activity. BCR (22q11.2) Hyper activation leads to uncontrolled growth and cancer. Why quantitative RT-PCR of CML patients? • For diagnosis and prognosis • Treatment response and monitoring • Early detection of relapse • Can be done on peripheral blood

CML-Diagnosis:

CML-Diagnosis Examination of the bone marrow by aspiration or trephine biopsy is not necessary to confirm the diagnosis of CML. but is usually carried out to: assess the degree of marrow fibrosis, to perform cytogenetic analysis and to exclude incipient transformation Blast cells in chronic phase number from 2% to 10%. Eosinophils and basophils are usually prominent; Megakaryocytes are small, hypolobated and very numerous. Occasionally, Gaucher-like cells are present.

CML- Diagnosis:

CML- Diagnosis The BM biopsy shows complete loss of fat spaces with dense hypercellularity. The reticulin content may be normal or modestly increased. Ability to reduce spleen size and restore and maintain a 'normal’ blood count with appropriate therapy.

CML-Advanced phases :

CML- Advanced phases Transition phase from chronic to blast The haematological picture in acceleration is very variable. It may differ little from chronic phase but blast cell numbers may be increased disproportionately. There may be anaemia in the presence of a normal leucocyte count. Platelet numbers may be greatly increased (> 1000 × 10 9 /L) or reduced (below 100 × 10 9 /L) in a manner not accounted for by treatment. The marrow also shows a picture no longer consistent with chronic-phase disease, often with increased numbers of blast cells or promyelocytes and/or increased fibrosis.

CML-Accelerated phase :

CML- Accelerated phase It’s defined by one or more of the following features: Blasts 10–19% of white blood cells in the peripheral blood and/or of nucleated bone marrow cells Pbl basophils ≥ 20% Persistent thrombocytopenia (< 100 × 10 9 /L) unrelated to therapy, or persistent thrombocytosis (> 1000 × 10 9 /L) unresponsive to therapy. Increasing spleen size and increasing white blood cell count unresponsive to therapy. Megakaryocyte proliferation in sheets or clusters in association with marked reticulin or collagen fibrosis

Blastic phase :

Blastic phase It’s defined by one or more of the following features Blasts > 20% of peripheral blood leucocytes or of nucleated bone marrow cells. Extramedullary blast proliferation Large foci or clusters of blasts in the bone marrow biopsy Frequently, this criterion is irrelevant because blast cell numbers in both sites have risen abruptly to exceed 80%. Their morphology is very variable. About 70% of patients have blasts classifiable generally as myeloid, such cells may be predominantly myeloblastic, monoblastic, erythroblastic .

Blastic phase :

Blastic phase L.N biopsy in cases with Lymphadenopathy shows nodal infiltration with blast cells that may be myeloid or lymphoid Chloroma or ‘granulocytic sarcomas’(which are discrete masses of immature leukaemia cells may develop at almost any site)

CML- Cytogenetics:

CML- Cytogenetics The Philadelphia chromosome t(9;22)(q34;q11) is found in 95% of patients and is caused by a reciprocal translocation which leads to a novel fusion protein BCR-ABL Detected in all myeloid cell lineages, in some B cells and in a very small proportion of T cells

prognosis:

prognosis In practice, patients who have a low leucocyte doubling time probably survive longer than those with more rapid doubling times. Moreover, the patient’s response to initial treatment does give some information about duration of survival; for example , a relatively low requirement for cytotoxic drugs to control the leucocyte count in the first year after diagnosis or a complete cytogenetic response to interferon α (IFN-α) are both good prognostic factors