MYELODYSPLASTIC SYNDROME

MODERATOR-DR SURESH HANAGAVADIPRESENTER- DR ARIJIT ROY

“We are put off by the fact that MDS is a heterogenous vaguely defined group of

conditions with seemingly ever changing names

Cole.P, Sateren W - Epimediological perspective on MDS &Leukemia

Leuk Res 1995 19 361-365

• First described in 1900 by Leube who used the term “Leukanamie”

• Subsequently it had undergone a trial of jargon

30’s - Refractory anemia

40’s- Preleukemic anemia

50’s- Preleukemia/RARS/ Refractory normoblastic anemia

60’s-Smoldering acute leukemia

70’s –CMML/Refractory anemia with excess myeloblasts• 1982- Myelodysplastic syndrome (Benett et al )

• WHO definition 2008• A group of clonal hematopoietic stem cell diseases

characterized by

Cytopenia

Dysplasia in one or more major myeloid cell lines

Ineffective hematopoiesis

Increased risk of development of AML

The threshold for cytopenia as recommended by the IPSS for risk stratification are • Hb < 10 g/dl• Absolute neutrophil count< 1.8x 109 /L• Platelets < 100 x 10 9/L

• PREDISPOSING FACTORS

HEREDITARY

A) Constitutional genetic disorders

Downs Syndrome: 10-30 times more risk

Trisomy 8 : Seen in 50% cases of MDS

Monosomy 7 : Seen in 50% cases of MDS.

 

B) Neurofibromatosis

C) Congenital neutropenia syndrome

Kostmann Agranulocytosis

Shwachman Diamond syndrome

• D) DNA repair defects

Fanconi anemia,

Ataxia telangiectasia

Bloom syndrome

• E) Mutagen detoxification(GSTq1-null)

Glutathione-S-Transferase. Studies show that GST- q1null

genotype increases risk by 4 times.

.

• ACQUIRED

These factors play a major role in secondary MDS/ t-MDS

a)Mutagen exposure

1.Genotoxic therapy- alkylating agents

2. Beta-emitter phosphorus; Used in the treatment of

Polycythemia Vera- 10-15% increased risk.

3. Topoisomerase(Topo-II) interactive agents like

anthracycline, etoposide.

4. Autologous stem cell transplantation- long term survivors

b) Environmental /occupational exposures

Exposure to benzene-5-20 fold increase in risk.

Other agents like solvents, petrochemicals,Insectide

c) Tobacco

Tobacco smoke contains a number of leukemogens like

nitrosamines, benzene and polonium-210

d) Senescence

e) Aplastic anemia

• ETIOLOGY

a) PRIMARY OR DE-NOVO Benzene exposure Cigarette smoking Agricultural chemicals Family h/o haematopoietic neoplasms Fanconi anemia, Shwachmann diamond, Diamond-Blackfan

• SECONDARY

Prior exposure to cytotoxic chemotherapy/radiation Alkylating agents cyclophosphamide, Topoisomerase II inhibitors Etoposide Risk increases with age & prolonged exposure to low - dose

chemotherapy Autologous transplantation for lymphoma-MDS seen in 12 %

Most cases develop within 5 years—poor outcome

Why Classify?• Unravel disease biology• Design accurate diagnostic tests• Predict prognosis • Develop novel therapies

FAB CLASSIFICATION OF MDS

• 1%BLAST SUBTYPE BLOOD BONE MARROW

REFRACTORY ANEMIA(RA)

<1%BLASTS DYSPLASIA; <5%BLASTS

REFRACTORY ANEMIA WITH RINGED SIDEROBLASTS(RARS)

<1%BLASTS DYSPLASIA; <5%BLASTS; >15%RINGED SIDEROBLASTS

REFRACTORY ANEMIA WITH EXCESS BLASTS(RAEB)

<5%BLASTS DYSPLASIA; 5-19%BLASTS

contd

SUBTYPE BLOOD BONE MARROW

REFRACTORY ANEMIA WITH EXCESS BLASTS IN TRANSFORMATION (RAEBt)

> 5%BLASTS

DYSPLASIA; 20-29%BLASTS OR AUER RODS

CHRONIC MYELOMONOCYTIC LEUKEMIA(CMML)

>1X109/L MONOCYTES DYSPLASIA; <30%BLASTS

WHO CLASSIFICATION OF MDS (2008) SUBTYPE BLOOD BONE MARROW

REFRACTORY CYTOPENIA WITH UNILINEAGE DYSPLASIA (RCUD)REFRACTORY ANEMIA (RA), REFRACTORY NEUTROPENIA(RN) , (REFRACTORY THROMBOCYTOPENIA (RT)

ANEMIA; NO OR RARE BLASTSUNICYTOPENIABICYTOPENIA

UNILINEAGE DYSPLASIA > 10% CELLS IN ONE MYELOID LINE WITH < 5% BLASTS <15%RINGED SIDEROBLASTS

REFRACTORY ANEMIA WITH RINGED SIDEROBLASTS

ANEMIA; NO OR RARE BLASTS

>15%RINGED SIDEROBLASTS; ERYTHROID DYSPLASIA; <5%BLASTS;

SUBTYPE BLOOD BONE MARROW

REFRACTORY CYTOPENIA WITH MULTILINEAGE DYSPLASIA (RCMD)

BI / PAN CYTOPENIAS; NO OR RARE BLASTS; NO AUER RODS; <1X109/L MONOCYTES

DYSPLASIA IN >10% OF THE CELLS >2 MYELOID LINES <5%BLASTS IN BM>15%RINGED SIDEROBLAST NO AUER RODS

REFRACTORY ANEMIA WITH EXCESS BLASTS 1

BI / PAN CYTOPENIAS; < 5%BLASTS; NO AUER RODS; <1X109/L MONOCYTES

UNI OR MULTILINEAGE DYSPLASIA; 5-9%BLASTS; NO AUER RODS

REFRACTORY ANEMIA WITH EXCESS BLASTS 2

CYTOPENIAS; 5-19%BLASTS; AUER RODS PRESENT; <1X109/L MONOCYTES

UNI OR MULTILINEAGE DYSPLASIA; 10-19%BLASTS; AUER RODS PRESENT

SUBTYPE BLOOD BONE MARROW

MYELODYSPLASTIC SYNDROME, UNCLASSIFIED(MDS-u)

CYTOPENIAS; NO OR RARE BLASTS; NO AUER RODS;

UNILINEAGE DYSPLASIA;<5% BLASTS;NO AUER RODS

5q-SYNDROME ANEMIA;NORMAL/INCREASED PLATELET COUNT;<5%BLASTS

NORMAL/INCREASED MEGAKARYOCYTES;<5%BLASTS;NO AUER RODS

CHILDHOOD MDS < 2 % BLASTSDYSPLASTIC CHANGES IN >10 % NEUTROPHILS

DYSPLASTIC CHANGES IN > 10 % ERYTHROID PRECURSORSDYSPLASTIC CHANGES IN > 10 % GRANULOCYTE PRECURSORSMICROMEGAKARYOCYTES,DYSPLASTIC CHANGES IN MGKS

SUBTYPE BLOOD BONE MARROW

MYELODYSPLASTIC SYNDROME, UNCLASSIFIED(MDS-u)

CYTOPENIAS; NO OR RARE BLASTS; NO AUER RODS;

UNILINEAGE DYSPLASIA;<5% BLASTS;NO AUER RODS

5q-SYNDROME ANEMIA;NORMAL/INCREASED PLATELET COUNT;<5%BLASTS

NORMAL/INCREASED MEGAKARYOCYTES;<5%BLASTS;NO AUER RODS

CHILDHOOD MDS < 2 % BLASTSDYSPLASTIC CHANGES IN >10 % NEUTROPHILS

DYSPLASTIC CHANGES IN > 10 % ERYTHROID PRECURSORSDYSPLASTIC CHANGES IN > 10 % GRANULOCYTE PRECURSORSMICROMEGAKARYOCYTES,DYSPLASTIC CHANGES IN MGKS

DIFFERENCES BETWEEN WHO AND FAB

The WHO system • Makes use of cytogenetic findings.• The category of RAEB-t was eliminated as it got included

within AML(>20%blasts).• CMML was removed and put in a new category of

myelodysplastic/myeloproliferative diseases.• Adds the subtypes 5q syndrome and unclassifiable MDS.• Recognizes the prognostic importance of % of bone marrow

blasts

INCIDENCE

• The mean age of presentation in the western population is 65 yrs, whereas in India it is 45 yrs.

• The incidence as reported by Aul et al in United States is 4.1 per 1,00,000.

• Rare in childhood, the median age of onset is 6yrs.

PATHOGENESIS

MDS : a stem cell disorder • It represents manifestation of the malignant transformation of myeloid

stem cell• The abnormal cells in MDS are clones derived from an abnormal stem cell

Apoptosis in MDS• Mechanism appears to be one of increased apoptosis of haemopoietic

precursors in the marrow,• Presence of cytopenias despite a typically hypercellular bone marrow.• For those patients undergoing leukaemic transformation,the cytopenias

arise due to maturation block of the malignant cells• Apoptosis is more prominent in early MDS, such as RA and RARS, than in

advanced MDS with excess myeloblasts

Ineffective Hematopoiesis• Colony forming capacities of pleuripotent stem cells and their

progeny are low or absent• Lower level of GM-CSF, M-CSF,IL 6 .IL 3, • CFU- GM less responsive to both G-CSF & GM-CSF• More dramatic in pts with RAEB or RAEB –t

Immunological abnormalities in MDS• Commonly encountered in MDS, suggesting that they may

play a role in the aetiology and pathogenesis of the disease.

• Particularly apparent in cases of hypoplastic MDS that share a number of features in common with aplastic anaemia, notably clinical presentation with macrocytosis and varying levels of dyserythropoiesis

• Acquired mutations in the PIG-A gene characteristic of paroxysmal nocturnal haemoglobinuria (PNH) are also encountered

Angiogenesis• Autocrine production of angiogenic molecules promotes

expansion of leukemic clone• Vascular endothelial growth factor(VEGF) and its receptor

VEGFR-1 And VEGFR-2 is overexpressed

Molecular basis of MDS• MDS is a preleukaemic disorder characterized by impaired

cellular differentiation that has the potential to transform to AML if this abnormality is coupled to enhanced survival and proliferation.

• The common chromosomal abnormalities found in MDS include loss of Y, monosomy 5, monosomy 7,trisomy 8, 20q – , abnormalities of 11q23, and deletions of 17p, 12p, 13q and 11q among others.

Genetic abnormalities in MDS• Mutations of the AML1 gene (also known as RUNX1 ) have

recently been recognized to occur in MDS, particularly where it is treatment - related or radiation - induced.

• Activating mutations of RAS , usually involving NRAS , are found in up to 20% of cases of MDS

• Class 1 mutation-mutation involving Tyrosine kinase GATA1 , PU.1 ( SPI1 ), CEBPA , MLL and TP53 .

• Class 2 mutation –mutation involving Transcription factors FMS (now called CSF1R ), KIT , FLT3 , PDGFRB and GCSFR

• Association of both Class 1 &2 – highly predisposed to MDS & AML

Epigenetic abnormalities• refers to alteration of gene expression without altering the

DNA sequence• Two important epigenetic modifications relevant to MDS, are

DNA methylation and histone modification.• Promoter methylation of p15INK4B – t-MDS• methylation of p15INK4B also seen in loss of Chr 7 and in pts

who progresses from RA to RAEB

MDS

ENVIRONMENTA

L

EPIGENETIC

APOPTOSIS

STEM CELL

DEFECTGENETIC LOSS

OF SIGNAL

ANGIOGENESIS

IMMUNOLOGIC

AL

MOLECULAR

GAIN OF FUNCTI

ON

Clinical features

• Asymptomatic - Many patients are diagnosed on routine

laboratory screening

• Fatigue, weakness, angina - as a result of anemia.

• Infections most commonly bacterial, predominate with skin

being the most common site. This is the most common cause

of mortality and morbidity in MDS.

• Autoimmune abnormalities (uncommon) - Seen in 14 %

of the patients. Most common is cutaneous vasculitis.• Cutaneous manifestations of MDS

Sweet syndrome

Granulocytic sarcoma

MORPHOLOGY OF BLASTS

• The standard criteria for a blast are Cell with a central nucleus Fine nuclear chromatin Prominent nucleoli High nucleocytoplasmic ratio Deeply basophilic and agranular cytoplasm

3 types of blasts have been found in the blood and bone

marrow of MDS.

TYPE I• Finely dispersed nuclear

chromatin• Prominent nucleoli• Variable N:C ratio , agranular

cytoplasm

TYPE IIThey resemble type I blasts but have primary granules in the cytoplasm(<20)

TYPE IIIThese are similar to type II blasts but have more than 20 granules in their cytoplasm

CYTOCHEMICAL IDENTIFICATION OF BLASTS

MYELOPEROXIDASE POSITIVE

SUDAN BLACK B POSITIVE

Morphological manifestations of dysplasia

• Dyserythropoiesis

Nuclear changes Nuclear budding Internuclear bridging Karyorrhexis Nuclear hyperlobation Megaloblastic changes

• Cytoplasmic changes Ring sideroblasts Vacuolization PAS positivity

Granular PAS positivity in proerythroblasts and homogeneous positivity in the later normoblasts

Giant multinucleate late normoblasts

• Dysgranulopoiesis

Small or unusually large size

Nuclear hypolobation(pseudo Pelger Huet)

Irregular hypersegmentation

Decreased granules, agranularity

Pseudo Chediak Higashi granules

Auer rods

• Dysmegakaryopoiesis

Micromegakaryocytes

Nuclear hypolobation

Multinucleation - normal megakaryocytes are

uninucleate with lobulated nuclei

LABORATORY FINDINGS

• PERIPHERAL BLOOD PICTURE• ERYTHROCYTES Anemia-variable RBC’s are macrocytic, macro ovalocytes seen. Reticulopenia Elliptocytosis, tear drop cells, stomatocytes seen. Basophilic stippling,Howell-Jolly bodies, normoblasts.

• OTHER ERYTHROCYTE CHANGES

• Increase in fetal hemoglobin

• Altered A,B, antigens on the surface.

• LEUKOCYTES

Neutropenia - 2nd most common cytopenia

Dysgranulopoiesis is seen by agranular or hypogranular neutrophils

Persistent basophilia of cytoplasm

Hyposegmentation (pseudo Pelger-Huet) of the nucleus

Hypersegmentation of the nucleus is seen sometimes

• OTHER DEFECTS

Enzyme defects such as Decreased myeloperoxidase, Decreased leukocyte alkaline phosphatase .

Causes functional impairment of the neutrophils like defective bactericidal, phagocytic and chemotactic properties.

PLATELETS

• Varying degree of thrombocytopenia

• Platelets may show agranular/hypogranular cytoplasm

• Giant platelets are seen

• Micromegakarocytes are seen. They have a single lobe nucleus

with cytoplasmic tags. Nucleus shows densely clumped

chromatin.

BONE MARROW ASPIRATE

• Well stained BM aspirate smears• At least 500 cells are to be counted• At least 30 megakaryocyte to be evaluated• Dysplastic features should be present in > 10 % cells

CELLULARITY In most cases it is hypercellular

But is hypocellular in Hypoplastic MDS

Erythropoeisis • Usually megaloblastic erythropoeisis • Feature of dyserthropoiesis• Some precursors may show Howell Jolly bodies• Vacoulization , basophilia and poor hemoglobinisation• Ring sideroblasts• PAS stain – may show granular positivity of normoblasts• Advanced cases – erythroid hypoplasia seen

Granulopoiesis• Usually myeloid hyperplasia• Hypogranulrity and hyposegmentation• Maturation arrest in myelocyte stage may be seen• Abnormal staining of primary granules seen in myelocyte &

promyelocytes. Granules may be larger than normal or completely absent.

• Irregular cytoplasmic basophilia seen• Diminished staining to MPO and SBB

• Thrombopoiesis• Usually normal or megakaryocytic hyperplasia• Micromegakaryocytes, multinucleated megakaryocytes , &

hypolobated megakaryocytes• Presence of > 10 % Micromegakaryocytes in a population

suggests MDS• CD 61 staining

TREPHINE BIOPSY IN MDS

Useful for determining • Cellularity of marrow• Abnormal localization of immature precursors (ALIP)• Reticulin fibrosis, Megakaryocytic dysplasia, Lymphoid

aggregate• Hypoplastic MDS• Increases the diagnostic accuracy & helps in refining the

IPSS score

Flowcytometry

• Erythroid abnormalities detected by

H- ferritin , CD71 ,CD105 in Glycophorin A • Abnormal maturation pattern in Granulocytes• For borderline dysplasia ,FC is highly suggestive for MDS

only if aberrant features are present in all three lineages

OTHER INVESTIGATIONS

• A) Immunophenotyping- do not play a major role in the diagnosis of MDS and need not be routinely performed

• However, various abnormalities are sometimes discernible, Low side scatter, reduced expression of normal myeloid

markers, Aberrant patterns of expression of markers like CD34 and to

a lesser degree CD117, often correlates with the blast percentage,

Coexpression of CD7 is significant for conferring a worse prognosis.

• B) Ferrokinetics- to assess erythropoiesis.• C) Haemoglobin electrophoresis or HPLC, to detect HbH and

HbF• D) Granulocyte function tests to demonstrate defective

phagocytosis• E) Platelet function tests to demonstrate reduced aggregation

and prolonged bleeding time.• F) Serum protein electrophoresis to assess immunoglobulins and detect paraprotein.

EVALUATION OF SUSPECTED MDS

• HISTORY Prior exposure to CT/RT Recurrent infections, bleeding gums• EXAMINATION Pallor/ bruising Splenomegaly• BLOOD COUNTS Hb, TLC, platelet count reticulocyte count• BLOOD FILM Macrocytosis, cytopenia, neytrophilia, monocytosis pseudo pelger huet anomaly,hypogranular neutrophils

• BONE MARROW ASPIRATE• BONE MARROW TREPHINE BIOPSY• BONE MARROW CYTOGENETICS ANALYSIS• EXCLUSION OF REACTIVE CAUSES OF DYSPLASIA Megaloblastic anaemia HIV infection Recent cytotoxic therapy Alcoholism Recurrent intercurrent infection

REFRACTORY CYTOPENIA WITH UNILINEAGE DYSPLASIA

• Includes Refractory Anaemia (RA), Refractory neutropenia (RN) Refractory Thrombocytopenia (RT)

• Majority of RCUD cases are RA. RN and RT are rare

• 10-20 % of all cases of MDS

• Older age 65-70 yrs • M:F equal prediliction• C/F due to type of cytopenia • Cytopenia refractory to hematinics , but respond to growth

factors

• Refractory Anaemia RBC are normochromic ,normocytic or normochromic

microcytic Anisopoilkilocytosis- none / marked Normal neutrophils and platelets BM in RA

Erythroid precursors- decreased / markedly increased

Dyserythropoiesis – slight/ moderate

• Myeloblasts ≤ 5% of nucleated BM cells• Neutrophils & megakaryocytes – normal or minimal dysplasia• BM- hypercellular due to increased rbc precursors• Ring sideroblasts if present are ≤ 15 % of erythroid precursors

• Genetics

RA includes del 20q , +8 , abnormality of 5 and / or 7

• Median survival is 66 months and risk for AML transformation at 5 yrs is 2 %

• 90-95% of pts with RA have low to intermediate IPSS score

RCUD: Refractory Neutropenia

• Most important to exclude secondary causes eg drugs ,toxins• Characteristics of Dysgranulopoiesis• Nuclear: hypolobation (pseudo-Pelger Huet), irregular

hypersegmentation• Cytoplasmic: hypogranularity, pseudo-Chediak Higashi

granules, Auer rods, small or abnormally large size

RCUD: Refractory Thrombocytopenia

• Evaluate >30 mgk’cytes• D/D from chronic autoimmune thrombocytopenia is critical• Features: Micromegakaryocytes, hypolobation, multiple

widely separated nuclei

REFRACTORY ANAEMIA WITH RING SIDEROBLASTS

• RARS is the MDS chacterized by anemia, morphological dysplasia in erythroid lineage and ring sideroblast ≥ 15 % of BM with no significant dysplasia in non erythrod lineage

• 3-11 % of MDS cases• Median age 60-73 yrs• Male : female - equal

• Ring sideroblasts – erythroid precursor with abnormal accumulation of iron within mitochondria

• RARS represents a clonal stem cell defects that manifests as abnormal iron metabolism in the erythroid lineage and results in ineffective erythropoiesis

• C/F

anaemia – usually moderate degree

thrombocytopenia or neutropenia

• Symptoms due to iron overload

MORPHOLOGY

PBS- Normochromic macrocytic/ Normochromic normocytic

anaemia Dimorphic pattern with majority normochromic rbc’s and

minor population of hypochromic cells

BM BM normocellular to markedly hypercellular

increase in erythroid precursors with lineage dysplasia

eg nuclear lobation & megaloblastoid features Hemosiderin laden macrophages - often abundant Myeloblasts ≤ 10% On iron stain ≥ 15 % of rbc precursors are ring sideroblasts • Prognosis 1-2% cases of RARS evolve to AML Median survival 69-108 months

REFRACTORY CYTOPENIA WITH MULTILINEAGE DYSPLASIA

• MDS with one or more cytopenias and dysplastic changes in two or more of the myeloid lineage

• ≤ 1% blasts in PBS and ≤ 5% in the BM

• 30 % of cases of MDS

• Slight predominance in males

• Age 70- 79

• More aggressive than refractory anemia, more likely to progress to AML

• Some consider it an intermediate disorder between refractory anemia and refractory anemia with excess blasts

• Poor prognosis if even 1% blasts in peripheral blood • Proposed modified criteria are refractory anemia, >10%

pseudo-Pelger-Huet anomalies, dysmegakaryopoiesis in ≥40% or micromegakaryocytes in ≥10%, and no 5q- syndrome

• Termed RCMD with ringed sideroblasts if ≥15% ringed sideroblasts

• Cytogenetic abnormalities include Trisomy 8,Monosomy 7

del 7q , del 20q as well as complex karyotype• Frequency of AML development at 2 yrs – 10 %• Overall survival – 30 months• Pts with complex karyotype have survival rate similar to

RAEB

• C/F – due to BM failure with cytopenia• Morphology

BM is hypercellular

Neutrophil dysplasia characterised by Hypogranulation nuclear hyposegmentation Pseudo pelger huet nuclei

• Erythroid precursors shows marked nuclear irregularity including

internuclear bridging nuclear budding Multilobation Megaloblastoid nuclei• Cytoplasmic vacoules are poorly defined, PAS positive

• Megakaryocyte abnormalities Non lobated nuclei Hypolobated nuclei/ binucleate/multinucleated Micromegakaryocyte

Bone marrow aspirate showing erythroid population with marked megaloblastic change and dyserythropoiesis. Blast cells with round and opened up chromatin and scant to moderate amount of pale blue cytoplasm. Most of these cells showed cytoplasmic vacuolation and had fine granules. (Inset) PAS staining on peripheral blood showing globular as well as diffuse PAS positivity in blasts as well as the nucleated RBCs

REFRACTORY ANAEMIA WITH EXCESS BLASTS

• MDS with 5-19 % myeloblasts in the BM or 2-19 % blasts in PB

• Because of difference in survival and evolution to AML,2 categories of RAEB are recognized

RAEB 1 – 5-9 % blasts in BM or 2-4 % in PB RAEB 2 - 10-19% blasts in BM or 5-19 % in PB

Presence of Auer rods in blasts qualifies as RAEB 2 irrespective of blast % .

• Approx 40 % of all MDS• Affects individuals over 50 yrs of age• Risk factors Environmental toxins eg pesticides Petroleum products Cigarette smoking Heavy metals

• PB smear shows abnormality in all three lines • Red cell anisopoikilocytosis• Large , giant or hypogranular platelets• Abnormal cytoplasmic granularity & nuclear segmentation of

neutrophils . Blasts are commonly present• BM is hypercellular• Degree of dysplasia varies• Erythropoiesis may be increased with macrocytic/

megaloblastoid changes

• Dyserythropoiesis includes internuclear bridging and lobulated nuclei

• Granulopoiesis characterized by small size with nuclei hypolobation (Pseudo pelger huet nuclei)/ nuclear hypersegmentation, cytoplasmic hypogranularity and /or pseudo Chediak- Higashi granules

• Megakaryopoiesis is normal to increased, shows tendency of cluster formation

• Dysmegakaryopoietic features include micromegakaryocytes but all forms and sizes can be seen

• Both erythropoiesis and megakaryopoiesis appears frequently towards the paratrabecular areas that are normally occupied by granulopoietic cells

• In minority of cases BM is hypocellular or normocellular. RAEB with hypocellular BM represents only a small proportion of hypoplastic MDS

• Blasts in RAEB form clusters and are located away from bony trabeculae and vascular structures – ALIP

• ALIP – CD 34 +

• Flow cytometry in RAEB – Precursor antigens like CD 34 and /or CD 117 .These cells are also positive for CD 38, HLA –DR and myeloid associated antigens CD13 and /or CD 33

• Asynchronous expression of Granulocytic maturation antigens CD15 ,CD 11b, and /or CD 65 in blast cells

• Antibody to CD 61 or CD 42b – idenification of micromegakaryocyte and other dysplastic forms

• Cytogenetic abnormalities – in 30-50 % of RAEB +8, del 5q , ,del 7q , del 20 q

• RAEB is characterized by progressive BM failure and increasing cytopenia

• RAEB 1 – 25 %• RAEB 2- 33 % • Median survival of 16 months for RAEB-1 and 9 months for

RAEB-2 • CD7 expression associated with poor prognosis

MYELODYSPLASTIC SYNDROME WITH ISOLATED del 5q

• Anaemia with or without other cytopenia and/or thrombocytosis in which the sole genetic abnormality is del 5q

• Myeloblasts ≤ 5% of nucleated BM cells and ≤ 1% of PB leucocytes

• Auer rods are absent• More in women • Median age 67 yrs

• Etiology Presumes loss of a tumour suppressor gene in deleted region Early growth phase response (EGR 1) and α – catenin

(CTNNA1), and as yet unidentified gene in 5q32 The RPS 14 gene that encodes a ribosomal protein has been

proposed as a candidate in the 5q syndrome

• Anaemia is often severe and usually macrocytic• Thrombocytosis is seen in majority of cases while

thrombocytopenia is uncommon• BM is usually hypercellular or normocellular and frequently

exhibits erythroid hyperplasia• Megakaryocytes are increased in no and are normal to slightly

decreased in size with conspicuously hypolobated and nonlobated nuclei

• Genetic abnormality Sole cytogenetic abnormality interstitial deletion of Chr 5

Recent report a small subset of patients with isolated del 5q may show a concomitant JAK2 V617F mutation but it is prudent to report them as del 5q and to note the presence of JAK2 V617F

• Subtype of refractory anemia with good prognosis

• Stable clinical course but often transfusion dependent causing frequent hemochromatosis

• 10% progress to AML• lenalidomide, a thalidomide analogue and immunomodulating

drug, has high response rate

Blasts with numerous platelets

Increased megakaryocytes withoverall PAS +ve cytoplasm,nuclear hypolobulation

MDS UNCLASSIFIABLE

• Subtype of MDS which lacks findings appropiate for classification into any other MDS category

• 3 possible instances for MDS-U

1. Patients with findings of refractory cytopenia with unilineage dysplasia (RCUD) or refractory cytopenia with multilineage dysplasia (RCMD) but with 1% blasts in PB

2. Cases of MDS with unilineage dysplasia which are associated with pancytopenia

3. Patients with persistent cytopenia with 1 % or fewer blasts in the blood and fewer than 5% in BM , unequivocal dysplasia in less than 10% of cells in one or more of the myeloid lineage and who have cytogenetic abnormalities considered as presumptive evidence of MDS

Findings

• Often Auer rods but less than 5% blasts, • isolated neutropenia without anemia, isolated

thrombocytopenia without anemia, • significant thrombocytosis, significant leukocytosis,

hypocellular bone marrow (<30% in younger individuals, <20% if age 60 or more) or myelofibrosis

• Some cases associated with prior aplastic anemia and monosomy 7

• Myelofibrosis: when present, often is difficult to obtain bone marrow aspirate; patients often have pancytopenia with dysplasia in 3 lineages

CHILDHOOD MYELODYSPLASTIC SYNDROME

• MDS in children is very uncommon ,accounting less than 5% of all hematopoietic neoplasms in patients less than 14 yrs

• This entity should be distinguished from “ secondary MDS” that follow congenital or acquired BM failure syndromes and from MDS that follows cytotoxic therapy for a previous neoplastic or non neoplastic condition

• This entity should be distinguished from MDS with Down Syndrome

• Most of childhood MDS become symptomatic rather early and transform to AML in a very short span

• Has an aggressive clinical couse irrespective of WHO subtype• Often associated with preexisting BM failure syndromes or

congenital abnormalities like Kostmann Syndrome Schwachmann Diamond syndrome, Fanconi anaemia NF 1 down syndrome, juvenile xanthogranuloma

• JMML is the commonest• Cytogenetic abnormalities- occurs in 60-70% of primary MDS

in children. Monosomy 7 is the most common

• DIFFERENCE BETWEEN ADULT AND CHILDHOOD MDS

Pts may not have increased blasts in their PB or BM RARS and MDS with del 5q are exceedingly rare in children Neutropenia or Thrombocytopenia is more likely seen Hypocellular bone marrow is more commonly observed in

childhood MDS

REFRACTORY CYTOPENIA OF CHILDHOOD (RCC)• It’s a type of MDS characterized by persistent cytopenia with

<5% blasts in BM and < 2% blasts in PB• BM trephine biopsy specimen is indispensable• 75% of children with RCC shows BM hypocellularity• Down syndrome related myeloid neoplasms are excluded• RCC is the most common MDS in childhood accounting for

50% of the cases• Equal incidence in both sexes

• Clinical features Malaise, bleeding , fever, infection Lymphadenopathy – secondary to local infection Hepatosplenomegaly is absent Platelet count < 150 x 10 9/L seen in 75% cases Hb <10g/dL seen in 50% cases WBC decreased with severe neutropenia seen in 25%

• PB Anisopoikilocytosis with macrocytosis, anisochromasia Platelets show anisocytosis and occasionally giant platelets Neutropenia with pseudo-Pelger Huet nuclei/ hypogranular

cytoplasm• BM Dysplastic changes in two different myeloid cell lineages or

exceed 10% in one single cell line

Erythroid changes• Nuclear budding• Internuclear bridging• Karyorrhexis• Nuclear hyperlobation• Megaloblastic changes

Granulocytic changes• Hyposegmentation with pseudo pelger huet• Hypo/agranular cytoplasm• Giant bands

• Cytoplasm- nucleus maturation asynchrony

Megakaryocytic changes• Detection of micromegakaryocytes is a strong indicator of

RCC

MINIMAL DIAGNOSTIC CRITERIA FOR MDS IN CHILDREN

• At least two of the following Sustained unexplained cytopenia( neutropenia,

thrombocytopenia , anemia) At least bilineage morphological myelodysplasia Acquired clonal cytogenetic abmormality in hematopoietic

cells Increased blasts > 5%

DIFFERENTIAL DIAGNOSIS

1. Vitamin B 12 and folic acid deficiency2. AML M63. HIV infection 4. Parvo virus B 19 infection5. Exposure to arsenic and other heavy metals6. Congenital Dyserythropoietic anemia7. Paroxysmal nocturnal hemoglobinemia8. G- CSF Therapy

DIFFERENCE BETWEEN AML M6 AND MDS COUNT 500 BM CELLS

All nucleated cells counted

Erythroblast > 50% Erythroblast <50%

< 20% total blasts and EP >50 % of all cells

Count non erythroid cells

>20 % NEC

<20 % NEC

AML M6

MDS

AML M0-M5

HYPOPLASTIC MDS

• 10-15% of MDS are of hypocellular type• Higher prevalence in women• Severe cytopenia and cellularity of the marrow <30% in those

who are <60 yrs of age OR < 20% in those > 60 yrs age• Majoriy of pt present with refractory anaemia• BM is hypocellular• No independent prognostic significance per se• D/D- Aplastic anaemia and hypocellular AML

MDS-F (MDS with Myelofibrosis)

• Significant marrow fibrosis in 10-15% MDS• Most cases: excess blasts, aggressive course• Unclear whether fibrosis has independent prognostic value• Blast % from aspirate smears alone may understage the

disease• CD34 on BMB may help• Cytogenetic abnormalities+• JAK2 - negative

SECONDARY/THERAPY RELATED MDS

• Occur post-chemotherapy or post-radiation therapy, benzene toxins

• Mean age of presentation is 10 yrs earlier than primary• PS – Anisopoikilocytosis & nucleated rbc • BM – normal or increased cellularity,trilineage dysplasia• Most cases are or RAEB type• t- MDS are of 2 types

a) MDS occuring many years after alkylating drugs use and associated with

• t- MDS are of 2 types

a) MDS occuring many years after alkylating drugs use &

associated with del 7q and del 5q

b) MDS occuring 2 yrs after Topoisomerase II inhibitors• Both subtypes frequently evolve into AML

IPSS risk-based classification system

Marrow blast percentage:

< 5 0

5-10 0.5

11-20 1.5

21-30 2.0

Cytogentic features

Good prognosis 0

(–Y, 5q- , 20q-)

Intermediate prognosis 0.5

(+8, miscellaneous single abnormality,

double abnormalities)

Poor prognosis 1.0

(abnor. 7, complex- >3 abnor.)

Cytopenias

None or one type 0

2 or 3 type 0.5

INTERNATIONAL PROGNOSTIC SCORING SYSTEM(IPSS)

RISK SCORE AML TRANSFORMATION %

MEDIAN SURVIVAL (YEARS)

LOW 0 19 5.7

INTERMEDIATE -1 0.5- 1.0 30 3.5

INTERMEDIATE -2 1.5 -2.0 33 1.2

HIGH 2.5 45 0.4

Applying WHO to Indian settings

• Indian MDS differs from MDS of West Younger age at presentation Cytopenias more severe at presentation Patients opted for less aggressive treatment Poorer treatment outcomes Infections, nutritional disorders: commoner Follow-up: Not always available Majority of pts had MDS-RA, MDS RAEB 1 & 2

PRINCIPLE OF MANAGEMENT OF MDS

• Management is individualized and guided by pt age, prognosis and toxicity of treatment

Low risk MDS (low and intermediate 1 risk grp of IPSS) is associated with longer survival

High risk MDS (high and intermediate 2 risk grp of IPSS) have high risk of transformation and shorter survival

• Low risk MDS – Erythropoietin , G-CSF, GM-CSF Immunosupressive therapy – ATG/ALG Antiangiogenic agents – Thalidomide For treatment of neutropenia – G- CSF, GM CSF

• HIGH RISK MDS Allogenic stem cell transplantation (SCT) Chemotherapy Newer therapy including 5-Azacytidine- methyl tranferase

inhibitor is the most promising therapy for improving the quality of life in MDS

CONCLUSION

• MDS can be effectively diagnosed and classified as per WHO 2008 classification

• MDS diagnosis and classification is currently in a transitional

phase from reliance almost entirely on cell morphology supplemented by cytochemistry and G-banded karyotyping, towards a new era in which molecular and perhaps immunophenotypic findings will be fully incorporated

• But in developing countries it is essential to rule out infections/ nutritional deficiencies especially among the elderly before considering MDS

REFERENCES• Swedlow SH,Campo E , Haris NL WHO classification of

Tumours of Hematopoietic and Lymphoid tissue, IARC press,Lyon 2008 , 94-107

• A F List, A.A Sandberg, Wintrobe Clinical Hematology ,11th Ed 1956-1977

• Barbara J Bain ,David M , Bone Marrow Pathology ,4th edition,208-225

• A.Victor Hoffbrand ,D, Catovsky ,Postgraduate Hematology 6th Ed ,503-512

• H D Deeg, DT Brown ,Hematological Malignancies –MDS, 4 th Ed , 18-132

• Tejinder Singh,Atlas and text of Hematology 1st Ed, 167-181 • www.pathologyoutlines. com

• John M Benett ,The MDS/MPD disorders , the interface Hematol Oncol Clinic N Am 17(2006) 1095- 1100

• Neelam Verma, S Verma ,Proliferative indices , cytogenetics,immunoproliferative & other prognostic parameters in MDS, IJPM 51(1) Jan 2008 97-101

• Wardrop D, Steensma DP. Is refractory anaemia with ring sideroblasts and thrombocytosis (RARS-T) a necessary or useful diagnostic category? Br J Haematol. 2009;144:809–817

• www.ashimages.org , American Society of Hematology• R. Hoffmann, Hematology: Basic Principles & Practice 4th Ed

1971- 1985