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Similar to Myelodysplastic syndrome according to WHO 2016
Myelodysplastic syndrome according to WHO 2016
- 1. 1 MYELODYSPLASTIC SYNDROMES PRESENTER :DR MADHURIREDDY MODERATOR :DR ANISHA T S
- 2. 2 CONTENTS DEFINITION EPIDEMIOLOGY ETIOLOGY PATHOPHYSIOLOGY CYTOGENETICS IN MDS MICROSCOPY/MORPHOLOGICAL FEATURES CLINICAL FEATURES WHO CLASSIFICATION 2016 DIFFERENTIAL DIAGNOSIS VARIANTS IMMUNOPHENOTYPING MANAGEMENT & PROGNOSIS PITFALLS ANCILLARY TECHNIQUES
- 3. Definition The myelodysplastic syndromes(MDS) are a group of clonal haematopoietic stem cell diseases characterized by ● Cytopenia, ● Dysplasia in one or more of the major myeloid lineages, ● Ineffective haematopoiesis, ● Recurrent genetic abnormalities & ● Increased risk of developing acute myeloid leukaemia (AML) 3
- 4. 4 The recommended thresholdsfor cytopenias established in the original International Prognostic Scoring System (IPSS) for risk stratification ● haemoglobin concentration < 10 g/dL, ● platelet count < 100 x 109/L & ● absolute neutrophil count < 1.8 x 109/L However, a diagnosis of MDS may still be made in patients ● with milder degrees of anaemia (haemoglobin< 13g/dL in men or < 12g/dL in women) ● or thrombocytopenia (platelets < 150 x 109 /L) if definitive morphologic &/or cytogenetic findings are present
- 5. 5 ● The morphologicalhallmark of MDS is dysplasia in one or more myeloid lineages. ● An increase in myeloblasts in the peripheral blood and/or bone marrow( blasts < 20 %) ● Recurrent cytogenetic abnormalities are present in 40-50% of cases, whereas acquired somatic gene mutations are seen in the vast majority of MDS cases at diagnosis
- 6. Epidemiology MDS occurs principallyin ●Older adults (median patient age: 70 years) ●Male predominance The annual incidence is ● 3- 5 cases per I00,000 population overall (non-age-corrected) ● 20 cases per I00,000 individuals aged > 70 years 6
- 7. Etiology PRIMARY/DENOVO SECONDARY 7
- 8. 8 ● Constitutional geneticdisorders Down syndrome, Trisomy 8 mosaicism Familial monosomy 7 ● Congenital neutropenia Kostmann syndrome ● Dyskeratosis congenita ● Shwachman Diamond syndrome ● Diamond Blackfan syndrome Inherited factors ● DNA repair defects Fanconi’s anemia, Ataxia telangiectasia, Bloom syndrome Xeroderma pigmentosum ● Neurofibromatosis 1 ● Germ cell tumors (embryonal dysgenesis) ● Mutagen detoxification(GSTq1-null)
- 9. 9 ● Senescence ● Mutagenexposure ● Environmental or occupational exposure (e.g.,benzene) ● Tobacco smoking ● Agricultural solvents ● Aplastic anaemia ● PNH ● Polycythemia vera ● Alkylating agents,P32,DNA topoisomerase II inhibitors Acquired Acquired factors
- 10.
- 11. 11 MDS Apoptosis Stem cell defect Angioge -nesis Epigenet -ic Immuno -logical Genetic loss of signalMolecular gain of function Environ- mental
- 12. 12Apoptosis is chieflybrought about by cysteine proteases called caspases which are activated by Receptor mediated extrinsic pathway Mitochondrial/intrinsic pathway( Bcl-2 mediated) APOPTOTIC INDEX High in early MDS Decreases with onset of AML Increased apoptosis & proliferation Low risk MDS –apoptosis is prominent High risk MDS-proliferation is prominent
- 13. 13 THEORIES OF PATHOPHYSIOLOGY INVOLVED INMDS DEVELOPMENT POTENTIAL TARGETS/COMPONENTS INVOLVED OVERALL RESULT OF ABNORMALITY Environmental/Aging Aging Increased BM apoptosis Decreased hematopoietic stem cell pool Environmental Exposures Smoking Radiation Benzene Viral Infections Chemotherapy Direct Toxicity to hematopoietic stem cells Telomere Abnormalities Potential decreased telomerase and subsequent telomere shortening • Impaired ability to renew stem cell pool. • Genetic Instability
- 14. 14 Genetic Alterations Cytogenetic Abnormalities Common Abnormalities: •5q- , 20q- • Y- , Trisomy 8 • 7q-/Monosomy7, 17p Syndrome • 11q23, 3q • p53 mutations, RAS mutations • Complex Cytogenetics •Typically unbalanced genetic loss • Numerous theories of tumor suppressor Loss • Multi-Hit progression from low risk MDS to AML •Genetic Instability Epigenetic Modulation •Hypermethylation •Acetylation Alterations Methylation and acetylation abnormalities lead to silencing of genes important in cell cycle , differentiation, apoptosis & angiogenesis
- 15. 15 Altered Bone Marrow Microenvironment AlteredBone Marrow Microenvironment Upregulation of cytokines :TNF-α, IFN- γ,TGF-β, IL-1β, IL-6,IL-11 •Alteration of growth, differentiation, angiogenesis •Immune modulation Alterations in Apoptosis via Signalling •Increased TNF-α levels •FAS: Increased Apoptosis •BCL-2 alterations •Increased apoptosis and proliferation in early stage MDS leading to hypercellular marrow with peripheral cytopenias • Decreased apoptosis and increased proliferation in later stage MDS leading to progression to AML Increased Angiogenesis •Increased VEGF •Possible Increase : FGF and EGF ,Angiogenin Increased Microvessel Density(MVD): role in pathogenesis not clearly elucidated but associated with progression to AML
- 16. 16 Immune Dysregulation •T cell Expansion •Bcell alterations •Increased T cells leading to potential attack on hematopoietic stem cells. •Etiology: Possible chronic antigenic stimulation Abnormal Differentiation •Cell Cycle Maturation arrest. •Altered Proliferation. •Transcription Factors alterations •Impaired maturation •Cytopenias • Progression to leukemia
- 17. 17 HSC’s inMDS have premalignant or malignant characteristics with defective maturation that often leads to uncontrolled proliferation Autocrine production of angiogenic molecules –promotes expansion of leukemic clone . Bone marrow neovascularity increases in proportion to marrow blast cell percentage. There is overexpression of VEGF-1/VEGF-2 receptors . Clonal chromosomal abnormalities occur in 30-50% of de novo MDS and in 80-90% of t-MDS.
- 18. Cytogenetics in MDS 3 GROUPSOF PATIENTS OF MDS ■ Normal karyotype ■ Balanced chromosomal abnormalities causing generation of fusion oncogenes ■ Complex karyotypes (> 3 abnormalities ) 18
- 19. 19 Chromosomal abnormality Frequency MDSoverall Therapy related UNBALANCED Gain of chromosome 8 10% Loss of chromosome 7 or del{7q) 10% 50% del(5q) 10% 40% del(20q) 5-8% Loss of Y chromosome 5% 25-30% Isochromosome 17q or t(17p) 3-5% Loss of chromosome 13 or del{13q) 3% del(11q) 3% del{12p) or t(12p) 3% del(9q) 1-2% idic(X)(q13) 1-2%
- 20. 20Chromosomal abnormality Frequency MDSoverall Therapy related BALANCED t(11 ;16)(q23.3;p13.3) 3% t(3;21)(q26.2;q22.1) 2% 1(1 ;3)(p36.3;q21.2) 1% t(2;11)(p21 ;q23.3) 1% inv(3)(q21.3q26.2) I t(3;3)(q21.3;q26.2) 1% t(6;9)(p23;q34.1) 1%
- 21. 21 CYTOGENETIC ABNORMALITIES ANDTHEIR ASSOCIATIONS IN MDS Cytogenetic abnormality Associated with Del 5q Good prognosis in elderly patients with thrombocytosis and macrocytic anemia Del 7q Differentiates hypocellular MDS from aplastic anemia Monosomy 7 Pediatric MDS-25% cases demonstrate it,JMML (MDS/MPN) Del 11q Intermediate risk Del 17p Dysgranulopoesis ,pseudo-Pelger-Huet anomaly with small vacuolated neutrophils and TP53 mutation,and poor response to therapy Monosomy 5 MDS-EB Del 12p CMML Trisomy 8 MDS-RS & CMML 11q23 Secondary/therapy related MDS
- 22. 22 RELATIONSHIP B/W CHROMOSOMALABNORMALITIES & BLOOD/BONE MARROW MORPHOLOGY Chromosomal abnormality Characteristic morphology i17q/17p loss Hypolobated neutrophils,abnormal chromatin clumping 3q26 Thrombocytosis Hypolobated small megakaryocytes Trisomy 8 Younger patient with less transfusion dependence,responsive to immunosuppressive therapy Del 20q Isolated thrombocytopenia with minimal dysplasia Del 5q Thrombocytosis ,unilobated megakaryocytes,macrocytic anemia
- 23. 23 COMMON GENE MUTATIONSIN MDS Gene mutated Pathway Frequency Prognostic impact SF3B1* RNA splicing 20-30% Favourable TET2* DNA methylation 20- 30% Conflicting /neutral ASXL1* Histone modification 15-20% Adverse SRSF2* RNA splicing 15% Adverse DNMT3A* DNA methylation 10% Adverse RUNX1 Transcription factor 10% Adverse U2AF1* RNA splicing 5- 10% Adverse TP53* Tumour suppressor 5-10% Adverse EZH2 Histone modification 5-10% Adverse ZRSR2 RNA splicing 5-10% Conflicting /neutral STAG2 Cohesin complex 5-7% Adverse IDH1/IDH DNA methylation 2 -5% Conflicting /neutral CBL* Signalling 5% Adverse BCOR* Transcription factor 5% Adverse NRAS Transcription factor 5% Adverse
- 24. Dysplastic features in MDS DYSERYTHROPOIESIS DYSMYELOPOIESIS DYSMEGAKARYOPOIESIS 24
- 25. Morphological manifestations of dysplasiain MDS 25 ● Small / unusually large size ● Nuclear hyposegmentation (pseudo-Pelger-Huet) ● Nuclear hypersegmentation ● Decreased granules; agranularity ● Pseudo-Chediak-Higashi granules ● Dohle bodies ● Auer rods ● Nuclear budding ● Internuclear bridging ● Karyorrhexis ● Multinuclearity ● Megaloblastoid changes ● Ring sideroblasts ● Vacuolization ● Periodic acid-Schiff (PAS) positivity DYSMEGAKARYOPOIESISDYSMYELOPOIESISDYSERYTHROPOIESI S ● Micromegakaryocytes ● Nuclear hypolobation ● Multinucleation
- 26. 26 DYSPLASIA IN MDS DYSGRANULOPOESIS DYSMEGAKARYOPOESIS Normal megakaryocyte Separated singlenuclei Micro- megakaryocyte Small binucleate megakaryocyte Round non lobulated megakaryocyte Normal erythroblast Nuclear bridging Nuclear lobulation Multiple nuclei Cytoplasmic granules Megaloblastic changes Normal neutrophil Pseudo Pelger– Huet anomaly Macrocytosis Chromatin clumping Hypo- ,agranulated cytoplasm Nucleus-cytoplasm maturation asynchrony
- 27. Dyserythropoiesis The nuclei oftwo polychromatic erythroid precursors in the upper right are connected by a thin chromatin strand (internuclear bridging); The two cells are unequal in size and the nucleus on the right is lobed 27
- 28. 28 Dyserythropoiesis and megaloblasticchanges (BM)
- 29. 29 Nucleated red cellprogenitors with multilobated or multiple nuclei (BM)
- 30. 30 Bone marrow smearshows marked erythroid hypoplasia, with occasional giant erythroblasts with dispersed chromatin and fine cytoplasmic vacuoles Bone marrow smear from a 47-year- old man with pancytopenia being chronically exposed to arsenic; there is marked dyserythropoiesis.
- 31. Dysmyelopoesis (A )Blood smearfrom a patient on G-CSF, showing a neutrophil with a bilobed nucleus and increased azurophilic granulation and a Myeloblast (B) 31 A
- 32. Dysplastic megakaryocytes Bone marrow aspiratesmear from a 37-year-old man with pancytopenia,showing hypolobated megakaryocytes & micromegakaryocytes. 32
- 33. 33 C, Pseudo-Pelger-Hüet cells,neutrophils with only two nuclear lobes instead of the normal three to four, are observed at the top and bottom of this field D, Megakaryocytes with multiple nuclei instead of the normal single multilobated nucleus.
- 34. 34 Large mononuclear megakaryocyte.Micromegakaryocyte
- 35. PERIPHERAL BLOOD EXAMINATION Do’sand dont’s Differential count of 200 cells Buffy coat evaluation in leucopenia Slides for the assessment of dysplasia should be made from freshly obtained specimens; specimens exposed to anticoagulants for > 2 hours are unsatisfactory 35
- 36. 36 PERIPHERAL SMEAR Dimorphicwith Macrocytosis and normochromic RBCs is observed Neutropenia in 50% cases Pince-nez nuclei along with cytoplasmic hypogranularity in neutrophils is characteristic. Monocytosis ,basophilia,eosinophilia or lymphocytosis may be present Thrombocytopenia in 30% cases
- 37. 37 MEGAKARYOCYTIC SERIES Giantplatelets Hypogranular platelets Agranular platelets ERYTHROID SERIES Ovalocytosis Macrocytosis Elliptocytosis Stomatocytes Tear drop cells Nucleated red cells Basophilic stippling Howell –Jolly bodies PERIPHERAL BLOOD FINDINGS MYELOID SERIES Pseudo-Pelger Huet anomaly Auer rods Hypogranulation Irregular contour of nuclei Hypo and hyper segmentation of nuclei Ring shaped nuclei
- 38. BONE MARROW ASPIRATE/BIOPSY PREREQUISITESIN ASPIRATE /IMPRINT /BIOPSY SMEARS Less than 0.5 ml of marrow should be aspirated for morphological assessment to avoid excessive dilution with peripheral blood cells. Minimum of 500 nucleated cells should be counted. Blast cells are counted as % of total marrow cells rather than % of non erythroid cells. Minimum of 30 megakaryocytes to be counted. 38
- 39. 39 BM ASPIRATE/IMPRINT SMEARS Hypercellular Dysplasia of hematopoetic cell lines Blast cells may demonstrate a diminished staining to MPO and SBB Megakaryocytes-N/C asynchrony- non lobated immature nuclei with mature granular cytoplasm BONE MARROW BIOPSY Helps in determining Cellularity ALIPS Reticulin fibrosis Megakaryocytic dysplasia Lymphoid aggregates Hypoplastic MDS
- 40. 40 MYELOID SERIES Defectivegranulation Nuclear hypolobation Auer rods in myeloid cells Maturation arrest at myelocyte stage Increase in monocytoid cells Abnormal localisation of immature precursors(ALIP) Pseudo Chediak Higashi granules Irregular nuclear hypersegmentation ERYTHROID SERIES Megaloblasts Nuclear bridging Ring sideroblasts Nuclear fragments Multinucleation Karyorrhexis Cytoplasmic vacuolation PAS stain positive Nuclear hyperlobation Multinuclearity BONE MARROW FINDINGS MEGAKARYOCYTIC SERIES Micromegakaryocytes Hypogranulation of megakaryocytes Multiple small nuclei of megakaryocytes Nuclear hypolobation Vacuolated megakaryocytes
- 41. 41ALIPS In health, •immature myeloid precursors are seen close to bony trabeculae and around blood vessels, • whereas developing erythroid cells and megakaryocytes are seen in intertrabecular spaces. In MDS, • myeloid precursors are displaced from trabecular margins and small clusters of myeloblasts and promyelocytes are sometimes seen in intertrabecular spaces. • The clusters are called ALIPS (abnormal localization of immature precursors) and may develop due to autocrine production of vascular endothelial growth factor.
- 42. 42 Marrow trephine stainedfor neutrophil elastase showing a ‘true ALIP
- 43. Clinical features Anemia(about one third of patients are dependent on red blood cell transfusions at diagnosis ) Neutropenia and/or thrombocytopenia are less common; Organomegaly(infrequent). Infections (bacterial pneumonias and skin abscesses) 43
- 44. WHO CLASSIFICATION OF MDS -2016 TheMDS category encompasses several distinct subtypes, which are defined by the ♠ number of cytopenias at presentation, ♠ the number of myeloid lineages manifesting dysplasia, ♠ the presence of ring sideroblasts, ♠ and the blast percentages in the blood and bone marrow In the current classification, only one cytogenetic abnormality, del(5q), is used in the definition of a specific MDS subtype 44
- 45. 45 Entity name Numberof dysplastic changes Number of cytopenias Ring sideroblasts as % of marrow erythroid elements Bone marrow and peripheral blood blasts Cytogenetics by conventional karyotype analysis MDS-SLD 1 1-2 <15%/<5% BM<5%, PB<1% no Auer rods Any,unless fulfills all criteria for MDS with isolated del(5q) MDS-MLD 2-3 1-3 <15%/<5% BM<5%, PB<1% no Auer rods Any,unless fulfills all criteria for MDS with isolated del(5q) MDS-RS MDS-RS- SLD MDS-RS- MLD 1 2-3 1-2 1-3 ≥15%/≥5% ≥15%/≥5% BM<5%, PB<1% no Auer rods BM<5%, PB<1% no Auer rods Any,unless fulfills all criteria for MDS with isolated del(5q) Any,unless fulfills all criteria for MDS with isolated del(5q)
- 46. 46 Entity name Numberof dysplastic changes Number of cytope- nias Ring sideroblasts as % of marrow erythroid elements Bone marrow and peripheral blood blasts Cytogenetics by conventional karyotype analysis MDS with isolated del(5q 1-3 1-2 None or any BM<5%, PB<1%, No Auer rods Del(5q)alone or with 1 additional abnormality,except loss of chromosome 7 or del(7q) MDS-EB MDS-EB-1 MDS-EB-2 1-3 1-3 1-3 1-3 None or any None or any BM 5-9% or PB 2-4%,BM <10% and PB <5%, No Auer rods BM 10- 19% or PB 5- 19% or Auer rods, BM & PB<20% Any Any
- 47. 47 Entity name Numberof dysplastic changes Number of cytopenias Ring sideroblasts as % of marrow erythroid elements Bone marrow & peripheral blood blasts Cytogenetics by conventional karyotype analysis MDS-U With 1% blood blasts With SLD & pancytopenia Based on defining abnormality 1-3 1 0 1-3 1-3 1-3 None or any None or any <15% BM<5%, PB=1% No auer rods BM<5%, PB=1% No auer rods BM<5%, PB=1%, No auer rods Any Any MDS defining abnormality
- 48. MDS with singlelineage dysplasia Cases that present with unexplained cytopenia or bicytopenia, 10% dysplastic cells in one myeloid lineage. The presenting lineage dysplasia and cytopenias(s) should be noted in the diagnostic conclusion. If SF3B1 mutation status is unknown, cases with 5- 14% ring sideroblasts and single lineage dysplasia be classified as MDS-SLD. 48
- 49. 49 Myelodysplastic syndrome with singlelineage dysplasia. Bone marrow smear from a 27- year-old man shows a dysplastic megakaryocyte. There is asynchronous nuclear- cytoplasmic maturation, with well-granulated cytoplasm and a non-lobated immature nucleus
- 50. 50 MDS-SLD Peripheral bloodsmear from a 56-year-old man shows granulocytic dysplasia. The neutrophil in the lower left is dysplastic, with moderately hypogranular cytoplasm and occasional Dohle bodies; the nucleus shows retarded segmentation.
- 51. 51DIFFICULT DIFFERENTIAL DIAGNOSESIN MDS-SLD Idiopathic cytopenia of undetermined significance Persistent cytopenia without dysplasia and without one of the specific cytogenetic abnormality(presumptive evidence of MDS) Hematologic and cytogenetic status should be monitored. MDS-MLD MDS-RS-SLD
- 52. MDS with ringsideroblasts MDS with ring sideroblasts is characterized by cytopenias morphological dysplasia ring sideroblasts constituting ≥ 15% of the bone marrow erythroid precursors. SF3B1 mutation in most cases, (≥5% marrow ring sideroblasts is diagnostic in such cases) 52
- 53. 53 Two categoriesof MDS-RS are recognized MDS-RS with single lineage dysplasia MDS-RS with multiple lineage dysplasia MDS with ring sideroblasts & single lineage dysplasia (MDS-RS-SLD) • anaemia, • dysplasia is limited to the erythroid lineage. MDS with ring sideroblasts and multilineage dysplasia (MDS-RS-MLD) • Any number of cytopenias, • Significant dysplasia in 2 or 3 haematopoietic lineages.
- 54. 54 Clinical features •Hepatomegaly • splenomegaly • Macrocytic/Normocytic normochromic anaemia. Peripheral blood • Dimorphic population of red blood cells Bone marrow aspirate MDS-RS-SLD • Increase in erythroid precursors with erythroid lineage dysplasia,( nuclear segmentation & megaloblastoid features) • Granulocytes/Megakaryocytes -no significant dysplasia (< 10% dysplastic forms). • Haemosiderin-laden macrophages are abundant. • Myeloblasts constitute < 5% of the nucleated bone marrow cells
- 55. 55Contd……. MDS-RS-MLD • Erythroidlineage dysplasia • Ringed sideroblasts • Significant dysplasia (≥ 10% dysplastic forms) in 1 or 2 non-erythroid lineages. • Iron stained aspirate smears - ≥ 15% (or ≥5% if SF3B1 mutation present)of the red blood cell precursors are ring sideroblats Bone marrow biopsy • Normocellular to markedly hypercellular with marked erythroid proliferation.
- 56. 56 Heterozygous mutations inSF3B1 SF3B1 encodes core component of U2snRNP spliceosome Altered splicing of mitochondrial iron transporter gene ABCB7 & other mitochondrial metabolism genes, Ineffective erythropoiesis & ring sideroblasts that characterize MDS-RS GENETICS IN MDS-RS
- 57. 57DIFFERENTIAL DIAGNOSIS AML MDS with excess blasts MDS with isolated del(5q) Non-neoplastic causes of ring sideroblasts, Alcohol, Toxins (e.g. lead and benzene), Drugs (e.g. isoniazid), Copper deficiency (which may be induced by zinc administration), Congenital sideroblastic anaemia
- 58. 58 A Blood smearwith dimorphic red blood cells and macrocytes.. B Bone marrow aspirate smear showing marked erythroid proliferation, with a dysplastic binucleated form
- 59. 59 Iron stain ofbone marrow aspirate showing numerous ring sideroblasts
- 60. 60 MDS –RS BM aspirateshowing numerous ring sideroblasts, several of which can be seen to have defectively haemoglobinized cytoplasm. Perls ’ stain × 100.
- 61. 61 BM aspirate, WHO MDS-RScategory, showing five erythroblasts, two of which show defectively haemoglobinized, heavily granulated cytoplasm.
- 62. MDS with multilineagedysplasia MDS characterized by one or more cytopenias and dysplastic changes in two or more of the myeloid lineages (erythroid, granulocytic, and megakaryocytic) Differential diagnosis MDS-RS-MLD MDS-U 62
- 63. 63 MDS with multilineage dysplasiaand complex cytogenetic abnormalities. Bone marrow section from a 37-year-old man with pancytopenia showing markedly increased megakaryocytes, many with dysplastic features.
- 64. 64 MDS-MLD Bone marrowsmear shows evidence of dysplasia in both the erythroid precursors and the myeloid precursors;
- 65. 65 MDS-MLD showing abinucleate micromegakaryocyte with its budding platelets.
- 66. MDS with excessblasts MDS characterized by 5-19% myeloblasts in the bone marrow or 2- 19% blasts in the peripheral blood but < 20% blasts in both bone marrow and blood ALIP is a common finding Divided into 2 subcategories MDS with excess blasts 1 (MDS-EB-1) MDS with excess blasts 2 (MDS-EB-2) 66
- 67. 67MDS with excessblasts 1 (MDS-EB-1) 5-9% blasts in the bone marrow or 2-4% blasts in the peripheral blood (but < 10% blasts in the bone marrow and <5% blasts in the blood) MDS with excess blasts 2 (MDS-EB-2) 10-19% blasts in the bone marrow or 5- 19% blasts in the peripheral blood The presence of Auer rods in blasts designates any MDS case as MDS-EB-2 irrespective of the blast percentage MDS with excess blasts and erythroid predominance MDS with excess blasts and fibrosis
- 68. 68 MDS with excessblasts and fibrosis In about 15% of cases of MDS, the bone marrow shows a significant degree of reticulin fibrosis (grade 2 or 3 according to the WHO grading system). They have been termed MDS with fibrosis (MDS-F) , and most belong to the MDS-EB category (MDS-EB-F). Differential diagnosis Therapy-related myeloid neoplasms, Myeloproliferative neoplasms, Lymphoid neoplasms Various reactive conditions(infections and autoimmune disorders)
- 69. 69 Bone marrow sectionfrom a case of MDS- EB-1 containing a focus of immature myeloid precursors Bone marrow biopsy from a case of MDS-EB- 2 showing a focus of immature cells,most of which stain positively for CD34
- 70. MDS with isolateddel(5q) MDS characterized by anaemia (with or without other cytopenias and/or thrombocytosis) & the cytogenetic abnormality del(5q) occurs either in isolation or with one other cytogenetic abnormality, other than monosomy 7 or del(7q). Myeloblasts constitute < 5% of the nucleated bone marrow cells and <1% of the peripheral blood leukocytes. Auer rods are absent. 70
- 71. 71 Bone marrow ♠Hypercellular / normocellular ♠ Erythroid hypoplasia ♠ Megakaryocytes - increased in number with dysplastic features ♠ Erythroid/Myeloid lineage -dysplasia is less pronounced ♠ The blast percentage is < 5% ♠ Ring sideroblasts may be present Peripheral blood ♠ The blast percentage is < 1%
- 72. 72 The presumedetiology is loss of a tumour suppressor gene or genes in the minimally deleted region (5q33.1) The size of the deletion and the breakpoints vary, but bands q31-q33 are invariably deleted. Haploinsufficiency of : ♠ RPS14 • Encodes a ribosomal structural protein→ p53 pathway activation . ♠ miR-145 and miR-146a • megakaryocyte abnormalities • thrombocytosis . ♠ CSNK1A 1 (encoding casein kinase 1A1) • WNT/beta-catenin pathway deregulation - proliferation of del(5q) clone ♠ APC (another WNT pathway regulator) and EGR1 DISEASE PATHOGENESIS
- 73. 73 A Bone marrowsection showing numerous megakaryocytes of various sizes, several with non-lobated nuclei. B Bone marrow aspirate smear showing two megakaryocytes with non-lobated, rounded nuclei.
- 74. 74 Bone marrow aspirateshowing a megakaryocyte of normal size with a hypolobated nucleus-MDS del(5q)
- 75. Myelodysplastic syndrome, unclassifiable Thediagnosis of MDS-U can be made in any of the following settings: I. There are findings that would otherwise suggest classification as other types but with 1% blasts in the peripheral blood on at least two separate occasions II. There are findings that would otherwise suggest classification as MDS - SLD MDS- RS-SLD with PANCYTOPENIA MDS with isolated del(5q) 75
- 76. 76III. There is persistent cytopenia < 2% blasts in the blood < 5% in the bone marrow, no significant(< 10%) unequivocal dysplasia in any myeloid lineage, & the presence of a cytogenetic abnormality considered presumptive evidence of MDS If characteristics of a specific subtype of MDS develop later in the course of the disease, the case should be reclassified accordingly.
- 77. Refractory cytopenia ofchildhood ♠ It is a provisional MDS entity characterized by persistent cytopenia, with <5% blasts in the bone marrow and < 2% blasts in the peripheral blood ♠ About 80% of children with RCC show considerable hypocellularity of the bone marrow ♠ Therefore should be differentiated from aplastic anemia and inherited bone marrow failure disorders 77
- 78. 78 Specimen Erythropoiesis GranulopoiesisMegakaryopoiesis Bone marrow aspirate Dysplastic changes and/or megaloblastoid changes Dysplastic changes in granulocytic precursors and neutrophils; <5% blasts Unequivocal micromega karyocytes; other dysplastic changes in variable numbers Bone marrow biopsy A few clusters of ≥20% erythroid precursors. Arrest in maturation,with increased number of proerythroblasts. Increased number of mitoses. No minimal diagnostic criteria Unequivocal micromegakaryocytes; IHC is obligatory (CD61,CD41);other dysplastic changes in variable numbers Peripheral blood Dysplastic changes in neutrophils Minimal diagnostic criteria for refractory cytopenia of childhood
- 79. 79 Bone marrow biopsyshows hypoplasia and patchy distribution of hematopoesis in particular erythropoiesis
- 80. 80 Bone marrow biopsy-CD61 immunohistochemistry shows dysplasia of megakaryocytes, with small, non-lobated nuclei or separated nuclei
- 81. 81 Criteria Refractory cytopeniaof childhood Aplastic anemia in children BM BIOPSY BM ASPIRATE BM BIOPSY BM ASPIRATE Erythropoie- sis Patchy distribution Left shift Increased mitosis Nuclear segmentation Multinuclearity Megaloblastoid changes Absent or single small focus; <10 cells with maturation Absent or very few cells,without dysplasia or megaloblastoid change Granulopoie- sis Marked decrease Left shift Pseudo-Pelger-Huet anomaly Agranularity/hypogra nularity of cytoplasm N/C maturation defects Absent or markedly decreased ,with very few small foci with maturation Few maturing cells,with no dysplasia Megakaryo- poiesis Marked decrease or aplasia Dysplastic changes Micromegakaryocyte s Micromegakaryocyte s Multiple separated nuclei Small round nuclei Absent or very few non dysplastic megakaryocytes Absent or few non dysplastic megakaryocytes COMPARISON OF THE MORPHOLOGICAL CRITERIA FOR HYPOPLASTIC REFRACTORY CYTOPENIA OF CHILDHOOD AND APLASTIC ANAEMIA IN CHILDREN
- 82. 82 Criteria Refractory cytopeniaof childhood Aplastic anemia in children BM BIOPSY BM ASPIRATE BM BIOPSY BM ASPIRATE Lymphocytes May be increased focally or dispersed May be increased May be increased focally or dispersed May be increased CD34+ precursor cells No increase No increase KIT+ (CD117+) precursor cells No increase No increase KIT+ (CD117+) mast cells Slightly increased Slightly increased
- 83. 83DIFFERENTIAL DIAGNOSIS Infection(e.g. cytomegalovirus, herpesviruses, parvovirus 819, visceral leishmaniasis) Vitamin deficiency (e.g. deficiency of vitamin B12, folate, vitamin E) Metabolic disorders (e.g. mevalonate kinase deficiency) Rheumatological disease Systemic lupus erythematosus Autoimmune lymphoproliferative disorders (e.g. FAS deficiency) Mitochondrial DNA deletions (e.g. Pearson syndrome) Inherited bone marrow failure disorders (e.g. Fanconi anaemia, dyskeratosis congenita, Shwachman-Diamond syndrome, amegakaryocytic thrombocytopenia, thrombocytopenia with absent radii, radioulnar synostosis, Seckel syndrome) Paroxysmal nocturnal haemoglobinuria Acquired aplastic anaemia during haematological recovery during or after immunosuppression
- 84. 84 Aplastic anaemia: Bonemarrow biopsy shows adipocytosis of bone marrow spaces; the few scattered cells are mainly lymphocytes, plasma cells macrophages,mast cells and occasional mature myeloid cells.
- 85. 85 RCC :Bone marrowaspirate smear showing abnormal nuclear segmentation of an erythropoietic precursor cell and a small megakaryocyte with a bilobed nucleus. RCC : Bone marrow biopsy showing a cluster of proerythroblasts without maturation.
- 86. Differntial diagnosis VitB12 & folic acid deficiency Exposure to arsenic and other heavy metals Congenital dyserythropoetic anemias Paroxysmal nocturnal hemoglobinuria HIV infection Parvo virus B 19 infection G-CSF therapy 86
- 87. 87 Hypoplastic AML MDS/MPN disorders AML-therapy related and AML in the elderly Primary myelofibrosis Accelerated phase of CML and other MPNs Myelocathexis Pelger –Huet anomaly Hereditary sideroblastic anemia Thiamine responsive anemia Giant platelet syndromes Hematological disorders associated with myelodysplasia
- 88. 88 Advanced age Medications Heavy metal intoxication Cigarette smoking Infections Metastatic cancer deposits bone marrow Exposure to aromatic hydrocarbons Autoimmune disorders Acquired conditions associated with non clonal myelodysplasia
- 89. Variants of MDS HYPOCELLULAR MDS SECONDARY /THERAPY RELATED MDS MDS-EO MDS WITH MARROW FIBROSIS FAMILIAL MDS (MYELOID NEOPLASMS WITH GERMLINE PREDISPOSITION) 89
- 90. 90 Secondary/therapy related Secondary ♠Bm biopsy shows increased reticulin, stromal edema,gelatinous marrow transformation ♠ Necrosis of bone marrow ♠ Trilineage dyspoiesis ♠ 10 years younger age of presentation compared to primary ♠ Mostly of MDS-EB type Therapy related ♠ MDS occurring after many years of alkylating drug intake associated with del 7q ♠ MDS after > 2 years of use of topoisomerase ii inhibitors
- 91. 91 MDS-f ♠ Diffuse coarsereticulin fibrosis , with or without ♠ Concomitant collagenisation ♠ Dysplasia in atleast 2 of the cell lineages ♠ Differential diagnosis AML –MLD Primary myelofibrosis CML in accelerated/blastic phase with marrow fibrosis MDS-Eo ♠ Clonal eosinophilia showing hyposegmented and dysplastic eosinophils
- 92. 92 Familial MDS Familieswith > 2 cases of ♠ MDS ♠ acute leukemia ♠ unexplained cytopenias ♠ cases with organ manifestations fitting into category of hereditary malignancy myeloid syndrome(HMMS) should be screened for familial MDS Mutations studied are ♠ Germline biallelic CEBPA ♠ Germline GATA2(childhood) ♠ Germline RUNX1,ANKRD26 & ETV6 ♠ Germline DDX41(elderly) ♠ Cases of bone marrow failure syndrome,telomere biology disorders,NF1 & noonan syndrome
- 93. 93 CLONAL HEMATOPOIESIS OFINDETERMINATE POTENTIAL(CHIP) Healthy older people with somatic MDS type mutations in hematopoietic cells like ♠ DNMT3A ♠ TET2 ♠ ASLX1 ♠ TP53 ♠ JAK2 ♠ SF3B1 High risk of development of hematologic malignancy Many of them do not develop MDS after many years of follow up Therefore current use of mutations in isolation to diagnose MDS may not be used
- 94. Immunophenotyping Delineating CD34+cells and further immunophenotyping to study abnormal phenotypes of CD34+ cells. Aberrant maturation patterns in granulopoiesis can predict morphological dysplasia. An emerging pathological population of CD34 or CD117 cells in low grade MDS could sugge.st evolution of disease 94
- 95. 95 ABERRANT PHENOTYPE OFBLASTS IN MDS OVEREXPRESSION OF CD34,CD117,CD38 DIM EXPRESSION OF CD34,CD38,CD4 ABNORMAL EXPRESSION OF CD4,CD11b,CD15,CD65 LACK/ABERRANTLY DIM CD13,CD33,HLA-DR CROSS LINEAGE EXPRESSION IN MYELOID BLASTS CD2,CD5,CD7,CD19,CD56,TdT
- 96. 96 Evaluation of suspectedMDS HISTORY • Prior exposure to chemotherapy/radiation • Recurrent infections,bleeding/bruising EXAMINATION • Pallor/bruising • Splenomegaly BLOOD COUNTS Hb, TLC, platelet count, reticulocyte count BLOOD FILM Macrocytosis, cytopenia(s), neutrophilia, monocytosis, pseudo-Pelger-Huet anomaly, hypogranular neutrophils BONE MARROW ASPIRATE/IMPRINT SMEARS,IRON STAIN ON BM ASPIRATE BONE MARROW TREPHINE BIOPSY,CD34,CD41/61 IHC IMMUNOPHENOTYPING OF BONE MARROW BONE MARROW CYTOGENETIC ANALYSIS
- 97. 97EXCLUSION OF REACTIVECAUSES OF DYSPLASIA • Megaloblastic anemia • HIV infection • Recent cytotoxic therapy • Alcoholism • Severe intercurrent illness BIOCHEMICAL TESTS • S.Iron • S.LDH • TSH • Red cell folate • S.Vit B12 OTHER TESTS • Viral markers including HIV,Parvovirus B19 • Autoimmune diseases workup • FLAER for PNH
- 98. Management Only hematopoieticstem cell transplantation offers cure MDS is refractory to cytotoxic chemotherapy regimens Other new drugs recently approved to ♠ Increase blood counts ♠ Decrease progression to leukemia ♠ Increase survival 98
- 99. 99 Epigenetic modifiers ♠Azacytidine ♠ Decitabine Both can cause myelosuppression worsening the condition Lenalidoamide ♠ More favourable toxicity profile ♠ Reverses anemia Immunosuppressive therapy ATG CYCLOSPORINE Anti-CD52 monoclonal antibody Alemtuzumab Hematopoietic growth factors Erythropoietin G-CSF Improve blood counts Improve Hb in those with low serum Epo
- 100. 100 Prognostic subgroup Definingcytogenetlc abnormalities Very good Loss of Y chromosome de1(11q) Good Normal del(5q) de1(12p) del(20q) Double, including del(5q) Intermediate del(7q) Gain of chromosome 8 Gain of chromosome 19 lsochromosome 17q Single or double abnormalities not specified in other subgroups Two or more independent non-complex clones The Comprehensive Cytogenetic Scoring System (CCSS) for myelodysplastic syndromes
- 101. 101 Prognostic subgroup Definingcytogenetlc abnormalities Poor Loss of chromosome 7 inv(3), t(3q) or del(3q) Double including loss of chromosome 7 or del(7q) complex (3 abnormalities) Very poor Complex (> 3 abnormalities) CCSS contd…
- 102. 102 PROGNOSTIC VALUE SCOREVALUES 0 0.5 1 1.5 2 3 4 Karyotype(CCSS group) Very good - Good - Intermed- iate Poor Very poor Bone marrow blast percentage ≤ 2% - >2%to< 5% - 5-10% >10% - Hemoglobin concentration(g/dL) ≥10 - 8 to <10 <8 - - - Platelets (x109 /L) ≥ 100 50 to<100 <50 - - - - Absolute neutrophil count (x109 /L) ≥0.8 <0.8 - - - - - The Revised International Prognostic Scoring System (IPSS-R) score values for myelodysplastic syndromes
- 103. 103 Five risk groupsare defined, on the basis of the total score of the parameters listed above: Very low: ≤ 1.5 Low: > 1.5 to 3 Intermediate:>3 to 4.5 High:>4.5 to 6 Very high:>6
- 104. 104 Adverse prognostic factorsin MDS Clinical Therapy-related MDS Blood Severe cytopenias Raised LDH or β2-microglobulin Marrow morphology Increased blasts Trilineage dysplasia Presence of ALIPS Immunophenotype CD7-positive blasts In vitro colony growth Leukaemic growth pattern Chromosome abnormalities Loss of chromosome 5 or 7 Deletion of chromosome 3q, 5q (excluding 5q syndrome), 7q, 17p Structural abnormality of chromosome 11q23 Complex chromosome abnormalities Karyotypic evolution Genetic/epigenetic abnormalities P53, RAS mutations Overexpression of WT1 p15 hypermethylation Telomere shortening Gene expression profile
- 105. 105 Hypothetical model ofevolution patterns in patients with MDS, based on growth advantage instability of the malignant clone Clonesize Time Clinical diagnosis of AML Group A Stable course The majority were ALIP negative Additional chromosome abnormalities were rare Group C Gradual increase in the percentage of marrow blasts ALIP-positive at diagnosis Rarely showed karyotypic evolution. They frequently succumbed to infections or haemorrhagic complications with or without evolution to acute leukaemia.
- 106. 106 Group B orD A rapid increase in blast cells Majority of these patients already had an abnormal karyotype at presentation Most were ALIP positive The sudden increase in blasts was frequently accompanied by additional chromosomal abnormalities Clonesize Time Clinical diagnosis of AML
- 107. Problems and pitfallsin the diagnosis of myelodysplastic syndromes 107 Diagnostic errors can result from a failure to assess clinical features, peripheral blood and bone marrow cytology, bone marrow histology and the results of cytogenetic analysis in all cases. A careful clinical assessment is essential, in order to exclude relevant systemic illness and exposure to drugs, alcohol, heavy metals and growth factors. Important pitfalls are relevant drug exposure that has not been disclosed to the pathologist and unexpected HIV positivity.
- 108. 108 Dyserythropoiesis • Congenitaldyserythropoietic anaemias • Thalassaemic conditions Megaloblastic erythropoiesis • Vitamin B12 and folic acid deficiency • Drugs interfering with DNA synthesis Sideroblastic erythropoiesis • Secondary to drugs or heavy metals , • Copper deficiency • Mitochondrial cytopathies • Thiamine - responsive anaemia with diabetes mellitus and sensorineural deafness. • Erythropoietic protoporphyria
- 109. 109 Differentiating hypoplasticMDS from aplastic anemia and hypoplastic AML • Immunophenotyping (IHC>ICC>FCM) • Good quality sections of trephine biopsy specimens. • Increased reticulin deposition and dysplastic megakaryocytes. • Percentage of blasts ALIPs vs Immature erythroid cells Lymphoid aggregates in MDS vs Non-Hodgkin lymphoma MDS with isolated thrombocytopenia vs autoimmune thrombocytopenic purpura.
- 110. 110 BM trephine biopsy sectionfrom a HIV - positive patient taking a high dose of zidovudine. The patient had megaloblastic erythropoiesis and a cluster of early megaloblasts was confused with ALIP; the linear nucleoli of the megaloblasts is a clue to their true nature.
- 111. 111 BM trephine biopsy sectionfrom a patient with MDS-RS showing large sheets of dysplastic erythroid cells separated by dilated sinusoids; the growth pattern appears so cohesive that the appearance could be confused with infiltration by carcinoma cells.
- 112. 112 BM trephine biopsy sectionfrom a patient with low grade T - cell lymphoma with secondary myelodysplasia; small hypolobated megakaryocytes are apparent.
- 113. 113 BM trephine biopsysections from a patient with hypoplastic MDS –EB (a) showing a disorganized marrow of low cellularity, (b) at higher power it is apparent that blast cells are increased
- 114. 114 Interrelationship between Aplasticanaemia, Myelodysplasia, Paroxysmal nocturnal haemaglobinuria and T-cell large granulocytic leukaemia
- 115. Ancillary techniques Conventionalkaryotyping FISH Gene sequencing Sanger’s sequencing Next generation sequencing(NGS) SNP array 115
- 116. 116 KARYOTYPING Bone marrowkaryotyping . Bone marrow aspiration in heparin is the preferred sample. 20 metaphases should be studied Denovo MDS-40-60% cases Therapy related -MDS-90% cases FISH More sensitive than G banding Materials -Bone marrow, blood smear ,marrow biopsy, touch smears ,cytospin preparations CLONAL ON CYTOGENETICS :when 2 cells show same addition or structural abnormality or 3 cells with loss of same chromosome CLONAL ON FISH: any abnormality after the validation of the probe and establishment of normal range Chromosomal abnormalities
- 117. 117 Gene sequencing Genes detectedby NGS IN Hematolgic neoplasms ABL1 HRAS KRAS ALK IDH1 NOTCH1 BRAF SNP array detects microdeletions JAK2 NPM1 FLT3 IDH2 PTPN11 KDR TP53
- 118. 118 1. Chapter 13.Diseases of White Blood Cells, Lymph Nodes, Spleen,and Thymus. Robbins and Cotran Pathologic Basis of Disease.9th edition :614-615 2. Chapter 4. Mixed phenotype acute leukaemia, the myelodysplastic syndromes and histiocytic neoplasms. Barbara J. B, David M. C, Bridget S. W . Bone marrow pathology. Fourth edition: 166-238 3. Chapter 6.Myelodysplastic syndromes. WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. Revised 4th edition : 95-120 4. David G.O, Sally B.K .Chapter 40.The myelodysplastic syndromes. Hoffbrand A.V, Catovsky D, Edward G.D. Postgraduate Haematology.5th edition :662-680 5. Chapter 25 .Myelodysplastic Syndrome. McKenzie B.S, Williams J.L. Clinical Laboratory Hematology.3rd edition :511-531 6. Manero G.G. Chapter 79.The Myelodysplastic syndromes. Greer P.J et al. Wintrobe’s Clinical Hematology.13th edition :1673-1687 7. Young N.S. Chapter 130.Bone Marrow Failure Syndromes including Aplastic Anemia and Myelodysplasia. Harrison T.R , Wintrobe M.M et al. Harrison’s principles of internal medicine.19th edition :662-672 References
Editor's Notes
- #5 most patients will have a cytopenia below at least one of these thresholds. In determining whether a patient is cytopenic, it is important to be cognizant of each laboratory's lower reference range and to take into account conditional variants of these values, such as due to ethnicity and sex. These are particularly important considerations in patients with a borderline low neutrophil count
- #6 It is important to recognize that the threshold of 20% blasts distinguishing AML from MDS does not reflect a therapeutic mandate to treat cases with >20% blasts as acute leukaemia.
- #13 Ineffective hematopoesis is evidenced by marrow hypercellularity ,PBS cytopenias and excess intramedullary cell death.
- #23 As a sole cytogenetic abnormality in the absence of morphological criteria, gain of chromosome 8, del(20q) and loss of Y chromosome are not considered definitive evidence of MDS; in the setting of persistent cytopenia of undetermined origin, the other abnormalities shown in this table are considered presumptive evidence of MDS, even in the absence of definitive morphological features.
- #24 • These genes are also reported to be mutated in clonal haematopoietic cells in a subset of healthy individuals (clonal haematopoiesis of indeterminate potential). b Either neutral prognostic impact or conflicting data.
- #25 dysplastic morphology may also be seen in healthy elderly individuals (affecting < 10% of marrow cells) and in a variety of non-clonal disorders including vitamin B12 and folic acid deficiency,heavy metal and alcohol poisoning, HIV and parvovirus infections and exposure to treatments such as anti-tuberculous therapy and granulocyte colony-stimulating factor (G-CSF).
- #26 (normal megakaryocytes are uninuclear with lobated nuclei)
- #34 Slides for the assessment of dysplasia should be made from freshly obtained specimens; specimens exposed to anticoagulants for > 2 hours are unsatisfactory
- #38 Acquired PHA TB,CLL,MM,VALPROIC ACID USAGE
- #39 Blasts have fine chromatin 2-4 nucleoli and pale basophilia of cytoplasm. In unilobed neutrophils chromatin is condensed and mature unlike open chromatin of myelocytes.
- #42 If 3-5 cells or > 5 cells of blasts in central portion then alip Megaloblasts have regular and uniform nuclei with linear nucleoli and negative for CD34
- #44 The majority of patients present with symptoms related to cytopenia. Bacterial pneumonias and skin abscesses infections, occurring particularly in patients with a neutrophil count < 1 × 109/L Parameters such as the myeloperoxidase index of granulocytes (MPXI), erythrocyte distribution width (RDW) and platelet distribution width (PDW) generated by automated cell counters are frequently abnormal and may become useful as markers for early MDS. Less than 0.5 ml of marrow should be aspirated for morphological assessment to avoid excessive dilution with peripheral blood cells
- #48 Marrow hypocellularity, increased fibrosis and an inflammatory infiltrate comprising plasma cells, eosinophils, lymphoid aggregates and areas of oedema are more common in TR-MDS than in primary cases
- #49 In the 2008 edition of this classification,MDS-SLD was called refractory cytopenia with unilineage dysplasia, and was divided into three subtypes: refractory anaemia, refractory neutropenia and refractory thrombocytopenia. The presenting lineage dysplasia and cytopenias(s) should be noted in the diagnostic conclusion.
- #53 Secondary causes of ring sideroblasts must be excluded
- #54 Aside from the presence of ring sideroblasts, the morphological features of MDS-RS-MLD are generally similar to those of MDS with multilineage dysplasia.
- #55 Dimorphic pattern with a major population of normochromic red blood cells and a minor population of hypochromic cells.
- #56 Ring sideroblasts are defined by ≥5 iron granules encircling 1/3rd or more of the nucleus
- #57 Core component of the U2 snRNP spliceosome (critical for RNA splicing)
- #58 Unlike in MDS-RS, patients with congenital sideroblastic anaemia tend to present at a much younger age and with microcytic (rather than macrocytic) anaemia
- #61 The presence of hypochromic red cell fragments, particularly when accompanied by basophilic stippling, is strongly suggestive of refractory anaemia with ring sideroblasts. Rarely, male\ patients may present with or develop a pronounced dimorphic picture due to acquired haemoglobin H disease
- #62 MGG × 100.
- #63 For assessing dysplasia, it is recommended that 200 erythroid precursors and 200 neutrophils and precursors be evaluated in bone marrow smear and/or trephine biopsy imprint preparations. Neutrophil dysplasia may also be evaluated in peripheral blood smears. At least 30 megakaryocytes should be evaluated for dysplasia in bone marrow smears, imprint preparations or sections.
- #64 A micromegakaryocyte is a megakaryocyte that is approximately the size of a promyelocyte or smaller, with a non-lobated or bi-lobated nucleus; this morphological finding is considered by most experts to be the most reliable and reproducible dysplastic feature in the megakaryocyte series
- #66 MGG × 100
- #67 Two subcategories, with differences in survival and incidence of evolution to acute myeloid leukaemia(AML), have been defined.
- #68 In the 2008 WHO classification, the category of erythroid/myeloid-type acute erythroid leukaemia (erythroleukaemia) encompassed cases of myeloid neoplasms in which maturing erythroblasts accounted for ≥50% of marrow cells and myeloblasts accounted for ≥20% of nonerythroid nucleated marrow cells. Such cases are now classified according to the blast percentage of all marrow cells,irrespective of the marrow erythroid percentage, and most (those with 5- 19% blood or bone marrow blasts) are now categorized as MDS-EB.
- #69 The presence of fibrosis is an independent prognostic parameter in MDS
- #71 Thrombocytosis is present in one third to one half of cases, whereas thrombocytopenia is uncommon Pancytopenia is rare It is recommended that cases otherwise fulfilling the criteria for MDS with isolated del(5q), but with pancytopenia be categorized as MDS, unclassifiable, because their clinical behaviour is uncertain.
- #72 Ring sideroblasts may be present and do not exclude the diagnosis of MdS with isolated del(5q), provided the other criteria are fulfilled
- #73 A small subset of patients with isolated del(5q) show concomitant JAK2 V617F or MPL WS1SL mutation, which does not appear to alter the disease phenotype or prognosis ; in some of these cases, the JAK2 mutation and del(5q) have been found in different clones. A subset of cases have SF3B1 mutation
- #76 In contrast, pancytopenia is allowed in both MDS with multilineage dysplasia and MDS with ring sideroblasts and multilineage dysplasia.
- #90 Secondary mds –trilineage dyspoesis,stromal changes like increased reticulin,stromal edema and gelatinous marrow transformation are observed.mostly MDS-EB. MDS-EO-Clonal eosinophilia with dysplastic and hyposegmented eosinophils. MDS-F-DDs-aml with mld,cml blast phase,pmf Therapy related 2 types 1.Alkylating agents for many years. With del 7q 2.Topoisomerase inhibitors for 2 yrs
- #93 Skin fibroblasts should be studied since germline mutation tissue should be non heamtopoietic
- #100 Drug therapy is for high risk mds in whom hsc transplantation is not possible.
- #108 Unstable haemoglobins are also sometimes associated with quite marked dyserythropoiesis
- #109 Unstable haemoglobins are also sometimes associated with quite marked dyserythropoiesis A useful feature is the lack of associated white cell changes – giant metamyelocytes and hypersegmented neutrophils– when megaloblastosis is a feature of MDS.
- #110 Hypocellular MDS has higher numbers of CD34 - positive cells and cells expressing proliferating cell nuclear antigen In contrast to cases of typical AML, pancytopenia is usual and peripheral blood blast cells are often absent or infrequent. The bone marrow aspirate is often hypocellular and may therefore not be optimal for diagnosis In hypoplastic MDS there may also be some circulating blast cells and an inadequate bone marrow aspirate, whereas there is no increase in blast cells in aplastic anaemia. Sections need to be examined carefully with high power magnification so that the proportion of blast cells can be estimated. If there are at least 20% blast cells the diagnosis is AML and, if blasts are increased but less than 20%, the diagnosis is MDS ALIPs vs immature erythroid cells Immunohistochemistry may help but it should be noted that not all blast cells express CD34 and, in addition, CD34 is not totally specific for myeloblasts since it can also be expressed by early erythroid cells (e.g. in megaloblastic anaemia or congenital dyserythropoietic anaemia) and by dysplastic megakaryocytes.
- #111 Paraffin - embedded, H & E× 100
- #112 Paraffin - embedded, H & E × 10.
- #113 Paraffin - embedded, H & E× 40.
- #114 Paraffin - embedded, H & E × 40 b)Paraffin - embedded, H & E× 100.
- #117 ISCN-International system for human cytogenetic nomenclature used for reporting.