Practical guidelines for diagnosing MDS and MDS/MPN … guidelines for diagnosing MDS and ... ring sideroblasts ... definitive diagnosis in some or even a majority of cases

Practical guidelines for diagnosing MDS and MDS/MPN overlap

Hans Michael KvasnickaUniversity of Frankfurt, Germany

[email protected]

Research funding & Consulting: Novartis, Incyte

Disclosure of speaker’s interests

Hans Michael Kvasnicka

MDS and MDS/MPN overlap are clonal hematopoietic stem-cell diseases

MDS MDS/MPN overlap

▪ ineffective hematopoiesis with dysplasia

▪ one or more peripheral cytopenias

▪ biologic course is highly variable characterized by variable increase in myeloblasts (<20%)

▪ may progress to AML with differing propensities depending on disease subtype

▪ anemia, usually mild (rarelynormal Hba) and dysplasia in one or more lineages, in combination with:‒ Leucocytosis

(WBC > 13 x109/L)b‒ Monocytosis

(monocytes >1 x109/L)‒ Thrombocytosis

(plts. >450 x109/L)‒ Splenomegaly associated

with marrow fibrosisc

a No erythrocytosisb May have normal WBC but usually no absolute neutropenia

(<1.8 x109/L)c The presence of splenomegaly or fibrosis alone is not a

MPN-like qualifying feature

MPN MDSMDS/MPN

Proliferationeffective hemopoiesis

ETPV

PMFCMLCELCNL

MPN-U

CMMLaCML

MDS/MPN-RS-TMDS/MPN-U

MDS-SLDMDS-MLD

MDS-RS-SLDMDS-RS-MLDMDS del(5q)

MDS-EBMDS-U

Dysplasiaineffective hemopoiesis

Morphological overlap in MPN, MDS/MPN, and MDS

Information needed by pathologist to diagnose MDS

▪ clinical history

▪ full CBC and WBC differential results

▪ knowledge of duration of cytopenias and possible other causes of cytopenia

▪ morphology review

▪ blood smear

▪ bone marrow aspirate or touch prep

▪ bone marrow biopsy

▪ complete bone marrow karyotype

▪ additional molecular data

Arber & Hasserjian, Hematology 2015

Morphologic Guidelines for the Diagnosis and Classification of MDS

▪ representative and well-prepared blood and bone marrow aspirate smears should be examined for:

dysplasia (10% or more rule)*

ring sideroblasts (iron stain of aspirate)

blast percentage

▪ representative bone marrow biopsy should be examined for:

dysplasia (in particular of megakaryocytes*)

blast (frequency & clusters)

stroma changes (myelofibrosis)

*Dysmegakaryopoiesis should be evaluated on ≥ 30 megakaryocytes

Morphologic manifestations of dysplasia

Dyserythropoiesis

▪ Nuclear

Nuclear budding

Internuclear bridging

Karyorrhexis

Multinuclearity

Nuclear hyperlobation

Megaloblastic changes

▪ Cytoplasmic

Ring sideroblasts

Vacuolisation

Periodic acid-Schiff positivity

Cantù Rajnoldi et al., Ann Hematol (2005) 84: 429–433

Dyserythropoiesis

Dysplasia vs. “non-clonal” dysplasia

▪ Dyserythropoiesis

B12/folate/copper deficiencies

methotrexate and otherchemotherapy

alcohol, toxic compounds(e.g. arsenic, zinc)

autoimmune conditions

malignancy associated(paraneoplastic)

aplastic anemia / PNH

infections (parvo, HIV)

Definition of sideroblasts

Mufti et al, Haematologica 2008; 93:1712

The Working Group definesthree types of sideroblast:

▪ Type 1: < 5 siderotic granules in the cytoplasm▪ Type 2: 5 or more siderotic granules, but not in a

perinuclear distribution▪ Type 3 or ring sideroblasts: 5 or more granules

in a perinuclear position, surrounding the nucleus or encompassing at least one third of the nuclear circumference

for the definition of MDS-RS the required number of ring sideroblastsremains at 15% as defined previously in the FAB and WHO classifications

Perinuclear Siderotic Granules Occurrence of Ringed Sideroblasts

Reactive▪ alcohol (plasma cell iron)▪ zinc▪ pyridoxine deficiency▪ drugs (isoniazid, cycloserine)

MPN and MDS/MPN▪ MDS/MPN-RS-T▪ PMF, (ET)

Hereditary▪ hereditary sideroblastic anemia


Dysgranulopoiesis

▪ small or unusually large size

▪ nuclear hypolobation

(pseudo-Pelger-Huët; pelgeroid)

▪ irregular hypersegmentation

▪ decreased granules; agranularity

▪ Pseudo-Chédiak-Higashi granules

▪ Auer rods


Dysgranulopoiesis


▪ Dysgranulopoiesis

cytokines (G-CSF)

bone marrow regeneration

post transplant


Dysmegakaryocytopoiesis

▪ Micromegakaryocytes

▪ Nuclear hypolobation

▪ Multinucleation

(normal megakaryocytes are

uninucleate with lobulated nuclei)


Dysmegakaryocytopoiesis


▪ Dysmegakaryopoiesis

infections (HIV)

chemotherapy

post transplant

down syndrome

MDS morphologic diagnosis: threshold for calling dysplasia▪ currently 10% of cells in any lineage

▪ no distinction between different specific dysplastic morphologies

▪ dysplasia is not specific for MDS

− significant dysplasia in bone marrow of normal volunteers

− dysplastic changes are even more frequent in patients with non-neoplastic cytopenias

▪ dysplasia is not always reproducible among pathologists

Font P Ann Hematol 2013;92:19Parmentier S Haematologica 2012;97:723

Matsuda A Leukemia 2007;21;678Della Porta MG Leukemia 2014;29:66

REACTIV

E /

NO

MD

S

MD

S

Recommendations for blast counting

▪ blasts in BM always counted as % of total cells, never as % of non-erythroid cells

▪ myeloid neoplasms with ≥50% erythroids and with blasts <20% of all cells will now be classified as MDS-EB, even if blasts are ≥20% of non-erythroid cells

▪ MDS-EB now includes most cases previously diagnosed as acute erythroleukemia (i.e. with ≥20% non-erythroid blasts, but 5-19% total blasts)

▪ pure erythroid leukemia will remain in AML

▪ Aspirate blast count is ‘gold standard’▪ CD34 immunostaining of biopsy is

important if aspirate is compromised

Identification of blast clusters by CD34

▪ frequency of CD34 pos. cells varies with the technique used

▪ normally around 2-4%, conservatively less than 5%

▪ clusters (3-5 myeloid precursors) are more important than numbers

Presence of CD34+ cell clusters is suggestedas an independent risk factor for MDS

▪ identified by IHC in 23% of patients

▪ more frequently in subgroups with excess of blasts (46% vs 14%; p<0.001)

▪ associated with shorter overall survival and leukemia-free survival

Della Porta et al, JCO 2009, 27:754-762

clusters aggregates sheets AML

cluster = 3-5 myeloid precursors // aggregate = >5 myeloid precursors

Pseudo ALIPs(Abnormally Localized Immature Precursors)

▪ erythroblasts (megaloblastic anemia) (Glycophorin C+, CD71+)

▪ promyelocytes (after G-CSF)(MPO+/CD34-/CD117-)

▪ monocytes(CD68+, CD163+)

▪ large size lymphoid cells(lymphoid markers+)

post G-CSF

MDS with bone marrow fibrosis

▪ 10-15% MDS

▪ MDS-EB >> other types

▪ no organomegaly

▪ increased MKs and dysmegakaryopoiesis

▪ clusters of CD34

▪ no or rare MK-blasts

Pagliuca et al, Br J Haematol, 1989Lambertenghi et al, Br J Haematol, 1991Maschek et al, Eur J Haematol, 1992 Buesche et, Leukemia 2008

Recurring chromosomal abnormalities and their frequency in MDS at diagnosisAbnormality MDS Therapy-related MDS

Unbalanced

+8* 10%

-7 or del(7q) 10% 50%

del(5q)/5q loss 10% 40%

del(20q)* 5-8%

-Y* 5%

i(17q) or t(17p) 3-5% 25-30%

-13 or del(13q) 3%

del(11q) 3%

del(12p) or t(12p) 3%

del(9q) 1-2%

idic(X)(q13) 1-2%

Balanced

t(11;16)(q23.3;p13.3) 3%

t(3;21)(q26.2;q22.1) 2%

t(1;3)(p36.3;q21.2) 1%

t(2;11)(p21;q23.3) 1%

inv(3)(q21.3q26.2)/t(3;3)(q21.3;q26.2) 1%

t(6;9)(p23;q34.1) 1%

*The presence of +8,

del(20q), or -Y as the

sole cytogenetic

abnormality in the

absence of morphologic

criteria is not considered

definitive evidence of

MDS.

In the setting of

persistent cytopenias

of undetermined

origin, the other

abnormalities shown

in this table are

considered

presumptive evidence

of MDS, even in the

absence of definitive

morphologic features.

Somatic mutations in MDS: a barrage of new information

Papaemmanuil E Blood. 2013;122:3616

Ribosomal proteins: RPS14

Epigenetic regulators: TET2, ASXL1

RNA splicing: SF3B1, SRSF2, U2AF1

Transcription factors: RUNX1, ETV6

Tyrosine kinase signaling: RAS

Tumor suppressor genes: TP53

Can mutations be used to diagnose MDS?

▪ 10% of healthy individuals >65 years harbor somatic MDS-type mutations in hematopoietic cells!

mostly DNMT3A, TET2, ASXL1, TP53, JAK2, SF3B1

allele burden typically 10-20% in blood, can be higher

associated with increased risk of subsequent hematologic malignancy and death

▪ presence of mutations is not sufficient to diagnose MDS: further study is needed (“CHIP”)

in the future, multiple mutations, particular combinations of mutations, and/or high allele burden may provide more specificity for diagnosing MDS

Jaiswal S NEJM 2014;371:2488Genovese G NEJM 2014;371:2477

Steensma D Blood 2015;126:9CHIP: “Clonal Hematopoiesis of Indeterminate Potential”

Indolent Myeloid Hematopoietic Disorders

Spectrum of Indolent Myeloid Hematopoietic Disorders

ICUS IDUS CHIP CCUS MDS

Somatic mutation - - +/- +/- +/-

Clonal karyotypic

abnomality

- - +/- +/- +/-

Marrow dysplasia - + - - +

Cytopenia + - - + +ICUS: idiopathic cytopenia of unknown significanceIDUS: idiopathic dysplasia of unknown significanceCHIP: clonal hematopoiesis of indeterminate potentialCCUS: clonal cytopenia of unknown significance

▪ heterogeneous group

▪ can evolve into MDS or AML, though the frequency of progression may differ among the four groups

▪ frequent monitoring of blood counts may be recommended

Do not overdiagnose MDS !Valent et al., Leuk Res 2007, 31, 727-736Valent et al., Am J Cancer Res 2011,1,531-541Steensma et al., Blood, 2015, 126, 9-16Kwok et al., Blood 2015, 126,2355-2361

New handling of MDS with ring sideroblasts

▪ MDS with ring sideroblasts (MDS-RS) will be broadened to include:

− traditional RARS (single lineage dysplasia)

− cases with multilineage dysplasia (will be a subcategory equivalent to RCMD-RS)

− cases with SF3B1 mutation and ≥5% RS

− if SF3B1 mutation status is negative or unknown, ≥15% RS will be required

▪ presence of SF3B1 mutation or RS will not affect RAEB or MDS with isolated del(5q)

Arber et al., Blood (2016) 127:2391-2405

MDS, unclassifiable (MDS-U): the group nobody likes!

▪ RCUD with pancytopenia

− cytopenias must be below IPSS levels:

− absolute neutrophil count <1.8 x 109/L, HGB<10 g/dL, PLT<100 x 109/L

− cutoff level of neutropenia should optimally be determined by each lab (ethnic variability in absolute neutrophil count)

▪ RCUD/RCMD with exactly 1% PB blasts

− 1% PB blasts must be measured on at least two separate occasions

▪ MDS without excess blasts or dysplasia, but with an MDS-defining cytogenetic abnormality

WHO 2016 MDS revision

▪ MDS with single lineage dysplasia

▪ MDS with multilineage dysplasia

▪ MDS with ring sideroblasts

and unilineage dysplasia

and multilineage dysplasia

▪ MDS with isolated del(5q)

▪ MDS, unclassifiable (MDS-U)

No excess of blasts

▪ MDS with excess blasts

– MDS with excess blasts-1

– MDS with excess blasts-2

Either ≥15% RS or ≥5% RS and SF3B1 mutation

− One additional chromosomal abnormality allowed

− Recommend testing for TP53 mutation

− Cases with significant granulocytic dysplasia excluded

− Stricter thresholds for pancytopenia

− Stricter definition of 1% BP blasts: must be recorded on at least 2 separate occasions

− Certain cytogenetic abnormalities remain as MDS-defining—but not mutations or microdeletions

Excess blasts

Arber et al., Blood (2016) 127:2391-2405

▪ MDS with single lineage dysplasia

▪ MDS with multilineage dysplasia

▪ MDS with ring sideroblasts

and unilineage dysplasia

and multilineage dysplasia

▪ MDS with isolated del(5q)

▪ MDS, unclassifiable (MDS-U)

▪ MDS with excess blasts

▪ MDS with excess blasts-1

▪ MDS with excess blasts-2

− Now will include most cases previously classified as acute erythroid leukemia, based on blast % of total marrow cells

No excess of blasts Excess blasts

WHO 2016 MDS revision

Arber et al., Blood (2016) 127:2391-2405

WHO diagnostic criteria of MDS subtypes

Dysplastic

lineages

Cytopenias Ring sideroblasts

as % of marrow

erythroid elements

Bone marrow (BM)

and peripheral

blood (PB) blasts

Cytogenetics by

conventional

karyotype analysis

MDS with single lineage dysplasia (MDS-SLD)

1 1 or 2 <5%2 BM Any, unless fulfills all criteria for del(5q)

MDS with multilineage dysplasia (MDS-MLD)

2 or 3 1-3 <5%2 BM Any, unless fulfills all criteria for del(5q)

MDS-RS with single lineage dysplasia (MDS-RS-SLD)

1 1 or 2 ≥15% / ≥5% BM Any, unless fulfills all criteria for del(5q)

MDS-RS with multilineage dysplasia (MDS-RS-MLD)

2 or 3 1-3 ≥15% / ≥5% BM Any, unless fulfills all criteria for del(5q)

MDS with isolated del(5q) 1-3 1-2 None or any BM del(5q) alone or with 1 additional abnormality except -7 or del(7q)

MDS-EB-1 0-3 1-3 None or any BM 5-9% or PB 2-4%, no Auer rods

Any

MDS-EB-2 0-3 1-3 None or any BM 10-19% or PB 5-19% or Auer rods

Any

MDS, unclassifiable (MDS-U)

with 1% blood blasts 1-3 1-3 None or any BM, no Auer rods Any

with single lineage dysplasia and pancytopenia

1 3 None or any BM Any

based on defining cytogenetic abnormality

0 1-3 <15% BM MDS-defining abnormality

Arber et al., Blood (2016) 127:2391-2405

MDS/MPN are clinicopathologically identified

▪ “In these relatively rare neoplasms, one must depend heavily on clinical features, since the pathologic and molecular features are not distinctive enough, or at least not well characterized enough, to provide a definitive diagnosis in some or even a majority of cases without the clinical features”

▪ MDS/MPN-like phases can be encountered in MPN or other hematologic neoplasms; these cases should be kept separate from true MDS/MPN

− CMML-like progression of PMF

− aCML or CNL-like progression of PV

Knowles Neoplastic Hematopathology, 3rd Edition

Bone marrow aspirate in CMML

▪ hypercellular with high M:E ratio due to increased granulopoiesis (resembles CML)

▪ blasts usually <5%

▪ typical “morphologic dissociation” between a granulocytic-rich BM and a monocytic-rich PB

▪ monocytes are hard to see and to distinguish from myelocytes, metamyelocytes, and band forms

▪ Esterase helps!!

BM examination in CMML is necessary

▪ AML-M4 and -M5b can simulate CMML in the PB

▪ CMML can have > 10% blasts in PB and/or BM or may be undergoing transformation to AML

▪ BM flow cytometry can help separating monocytes from blasts

▪ karyotype e.g., 11q23

▪ monocytic proliferation can be more pronounced in BM than PB (oligomonocytic CMML)*

*Orazi A, Germing U. Leukemia 2008;22:1308-19

▪ cytogenetic abnormalities

▪ mutations can be identified in at least

90% of CMML cases

▪ most frequently found mutations

▪ TET2▪ SRSF2▪ ASXL1

▪ ASXL1 is a predictor of aggressive

disease behavior and has been

incorporated into a prognostic

scoring system alongside karyotype

and clinicopathologic parameters.

Molecular findings in CMML Gen mutiert (n,%)

ASXL1 125 (40%)

TET2 151 (58%)

SRSF2 101 (46%)

RUNX1 39 (15%)

NRAS 29 (11%)

CBL 27 (10%)

JAK2 21 (8%)

KRAS 20 (8%)

ZRSF2 15 (8%)

IDH2 13 (6%)

SF3B1 13 (6%)

U2AF35 11 (5%)

EZH2 8 (5%)

FLT3 8 (3%)

DNMT3A 5 (2%)

NPM1 3 (1%)

IDH1 1 (<1%)

KIT 1 (<1%)

TP53 2 (1%)

Itzykson R et al, J Clin Oncol, 2013Damm F et al, Leukemia, 2013Such E et al, Haematologica, 2011Elena C et al. Blood. 2013Itzykson R, J Clin Oncol. 2013Peng J et al. Eur J Haematol. 2015

TET2

SRSF2

ASXL1

Updates to CMML

▪ additional PB requirement of ≥10% monocytes

▪ integration of mutations could help supporting a CMML diagnosis (particularly TET2 plus SRSF2) and/or prognostic information (ASXL1)

Ricci C et al. Clin Cancer Res. 2010 ; Schuler E, et al. Leuk Res. 2014; Cervera N, et al. Am J Hematol. 2014 Jun;89(6):604-9. Meggendorfer M et al. Blood 2012; Itzykson R et al. J Clin Oncol 2013; Federmann B et al. Hum Pathol. 2014; Patel B et al. Int J Hematol. 2015; Gerstung M, et al. Nat Commun. 2015

▪ MDS- vs. MPN-like

CMML dysplastic (WBC, <13 ×109/L)

CMML proliferative (≥13 × 109/L); this subtype has more frequent RAS or JAK2 mutations and splenomegaly

▪ Refined blast count

CMML-0: <2% blasts in PB; <5% blasts in BM

CMML-1: 2‒4% blasts in PB; 5‒9% blasts in BM

CMML-2: 5‒19% blasts in PB; 10‒19% in BM, or when Auer rods are present irrespective of the blast count

▪ Persistent peripheral blood monocytosis ≥1×109/L and ≥10% of the WBC

▪ Not meeting WHO criteria for BCR-ABL1+ CML, PMF, PV or ETa

▪ No rearrangement of PDGFRA, PDGFRB, FGFR1, or PCM1-JAK2 fusion (should be specifically excluded in cases with eosinophilia)

▪ Fewer than 20% blastsb in the blood and bone marrow

▪ Dysplasia in one or more myeloid lineages. If myelodysplasia is absent or minimal, the diagnosis of CMML may still be made if the other requirements are met, and an acquired, clonal cytogenetic or molecular genetic abnormalityc is detected, --or-- - the monocytosis has persisted for at least 3 months and all other causes of monocytosis have been excluded

Diagnostic criteria for CMML (Update 2016)

a Cases of MPN can be associated with monocytosis or they can develop it during the course of the disease. These cases may simulate CMML. In these rare instances, a previous documented history of MPN excludes CMML, while the presence of MPN features in the bone marrow and/or of MPN-associated mutations (JAK2, CALR or MPL) tend to support MPN with monocytosis rather than CMML.

b Blasts and blast equivalents include myeloblasts, monoblasts and promonocytes. Promonocytes are monocytic precursors with abundant light grey or slightly basophilic cytoplasm with a few scattered, fine lilac-coloured granules, finely-distributed, stippled nuclear chromatin, variably prominent nucleoli, and delicate nuclear folding or creasing. Abnormal monocytes are excluded from the blast count.

c The presence of mutations in genes often associated with CMML (e.g. TET2, SRSF2, ASXL1, SETBP1) in the proper clinical contest can be used to support a diagnosis. It should be noted however, that some of the mutations can be age related or be present in subclones. Therefore caution would have to be used in the interpretation of these genetic results.

Arber et al., Blood (2016) 127:2391-2405

Early CMML (oligomonocytic CMML)

▪ CMML with a bone marrow predominantpresentation

▪ PB monocytes ≥10% but less than 1.0 x 109/L

− threshold ≥0.5 x 109/L (proposed)− BM monocytes ≥10%

CD14 (>10%)

aCML becomes a better defined entity

▪ it has its own molecular profile:

− SETBP1 mutations in 15-32% and ETNK1 mutations in 9% ETNK1 coexistent with SETBP1 in 33%

− JAK2, CALR mutations rare or absent

− CSF3R mutations absent or very rare (<10%)

▪ can be separated from other MDS/MPN subtypes and fromMPN (e.g., CNL, cases of MPN in AP)

▪ aCML has poorer survival than other MDS/MPN or MPN; novel targeted approaches much needed

▪ main distinction is with chronic neutrophilic leukemia (CNL)

Wang SA et al. Blood 2014;123:2645; Piazza R et al. Nat Genet 2013;45:18; Gotlib J et al. Blood 2013;122:1707; Maxson JE et al. NEJM 2013;368:1781, Pardanani A et al. Leukemia 2013;27:1870; Gambacorti-Passerini CB, et al. Blood. 2015; 125:499.

▪ pseudo-Pelger-Huet nuclear abnormalities

− abnormal condensed nuclear chromatin

− bizarr segmentation of nuclei

− atypical cytoplasmic granularity

▪ syndrome of abnormal chromatin clumping in granulocytes has to be regarded as a variant of aCML

Dysgranulopoiesis is key to diagnose aCML

▪ hypercellular with predominanceof the granulocytic series

− increase in myeloid precursors− reduced erythropoiesis− variable degree of reticulin fibrosis

▪ dysplastic megakaryocytes

BM histology in aCML

▪ Peripheral blood leukocytosis due to increased numbers of neutrophils and their precursors (promyelocytes, myelocytes, metamyelocytes≥10% of leukocytes)

▪ Dysgranulopoiesis, which may include abnormal chromatin clumping▪ Not meeting WHO criteria for BCR-ABL1-positive chronic myelogenous

leukaemia, primary myelofibrosis, polycythemia vera or essential thrombocythemiaa

▪ No rearrangement of PDGFRA, PDGFRB, FGFR1, or PCM1-JAK2 ▪ No or minimal absolute basophilia; basophils usually <2% of leukocytes ▪ No or minimal absolute monocytosis; monocytes <10% of leukocytes ▪ Hypercellular bone marrow with granulocytic proliferation and

granulocytic dysplasia, with or without dysplasia in the erythroid and megakaryocytic lineages.

▪ Less than 20% blasts in the blood and bone marrow

Diagnostic criteria for aCML (Update 2016)

Cases of PV or ET particularly if in accelerated phase and/or in Post-PV or Post-ET myelofibrotic stage, if neutrophilic, may simulate aCML. A previous history of MPN, the presence of MPN features in the bone marrow and/or MPN-associated mutations (in JAK2, CALR or MPL) tends to exclude a diagnosis of aCML.

A diagnosis of aCML is supported by the presence of SETBP1 and/or ETNK1 mutations. The presence of CSF3R mutations is uncommon in aCML; if detected, it should prompt a careful morphologic review to exclude an alternative diagnosis of CNL or other myeloid neoplasm.

Arber et al., Blood (2016) 127:2391-2405

Megaloblastoid changes, ring sideroblasts, thrombocytosis and (often) MPN-like megakaryocytes

MDS/MPN-RS-TThe overlap syndrome promoted to full entity

[MDS/MPN-RS-T]

[MDS/MPN-RS-T]

▪ vast majority (>80%) of cases are mutated for SF3B1

▪ often co-mutated with JAK2 V617F (rarely MPL and CALR)

▪ median survival is better in SF3B1-mutated patients than in SF3B1-non-mutated patients (6.9 and 3.3 years, P=0.003)

Papaemmanuil E NEJM 2011;365:1384Patniak MM Blood 2012;119:5674

Bejar R JCO 2012;30:3376Malcovati L Blood 2011;118:6239

Cazzola M Blood 2013;121:260Visconte V Blood 2012;120:3173

Mutation profile and prognosis in MDS/MPN-RS-T

▪ Clinical presentation

Thrombocytosis

Need for cytoreduction

▪ BM morphology

Large megakaryocytes with bulbous nuclei

▪ Genetic profile

JAK2 mutation (50-60%)

Rare CALR/MPL

MPN-like

▪ Clinical presentation

Macrocytic anemia

Transfusion requirement

▪ BM morphology

Erythroid dysplasia

Ring sideroblasts

▪ Genetic profile

SF3B1 mutation (80-90%)

MDS-like

Schmitt-Graeff A Haematologica 2008; Wang SA Leukemia 2006; Malcovati L Blood 2011 and Blood. 2014 Jeromin S Haematologica 2015; Zoi K Int J Hematol. 2015.

MDS/MPN-RS-T: now promoted to a full entity

▪ Anaemia associated with erythroid lineage dysplasia with or withoutmultilineage dysplasia, ≥15% ring sideroblasts*, <1% blasts in peripheral blood and <5% blasts in the bone marrow

▪ Persistent thrombocytosis with platelet count ≥450 x 109/L

▪ Presence of a SF3B1 mutation or, in the absence of SF3B1 mutation, no history of recent cytotoxic or growth factor therapy that could explainthe myelodysplastic/myeloproliferative features**

▪ No BCR-ABL1 fusion gene, no rearrangement of PDGFRA, PDGFRB or FGFR1; or PCM1-JAK2; no (3;3)(q21;q26), inv(3)(q21q26) or del(5q)***

▪ No preceding history of MPN, MDS (except MDS-RS), or other type of MDS/MPN

Diagnostic criteria for MDS/MPN-RS-T(Update 2016)

*≥15% ring sideroblasts required even if SF3B1 mutation is detected

**A diagnosis of MDS/MPN-RS-T is strongly supported by the presence of SF3B1 mutationtogether with a mutation in JAK2 V617F, CALR or MPL genes

***In a case which otherwise fulfills the diagnostic criteria for MDS with isolated del(5q)-No or minimal absolute basophilia; basophils usually <2% of leukocytes

Arber et al., Blood (2016) 127:2391-2405

▪ MDS/MPN, U may include MPN patients in whom their chronic phase was not previously detected, and who initially present in transformation with myelodysplastic features

▪ if the underlying myeloproliferative process cannot be identified, the designation of MDS/MPN,U is appropriate in these cases

MDS/MPN-like phases or progression of classical MPN

MDS/MPN-U

MDS/MPN-U≠

MPN-U

WHO 2016 revision of MDS/MPN

▪ Refractory anemia with ring sideroblasts associated with marked thrombocytosis (MDS/MPN-RS-T)

▪ Atypical CML, BCR-ABL1 negative (aCML)

▪ Chronic myelomonocytic leukemia(CMML)

▪ Moved from a provisional to a full entity and new name

▪ Common co-mutation of JAK2 and SF3B1

▪ Integration of NGS: SETBP1, CSF3R, ETNK1

▪ CNL: common co-mutation CSF3R/SETBP1

*Locatelli F, Niemeyer CM. Blood. 2015 Feb 12;125:1083-90Mutations are insufficient to diagnose MDS/MPN on their own

They rather represent a usefully complement to a clinicopathologic-based diagnosis

▪ Mutation profile (SRSF2/TET2/ASXL1) helpful in supporting diagnosis and providing prognosis

▪ Cases with NPM1 mutation or 11q23 rearrangement should be followed carefully for AML

▪ Emphasize careful blast/ promonocyte/monocyte count to distinguish from AML

▪ CMML-0,-1,-2; CMML MDS and MP subtypes

Arber et al., Blood (2016) 127:2391-2405

Algorithm for MDS & MDS/MPN diagnosis

Step 1: Determine the presence of dysplasia

Exclude reactive conditions



Step 2: Are bone marrow blasts > 20%?

Exclude bcr/abl+ cases



Step 2: Are bone marrow blasts > 20%? yes AML

Step 3: Features of myeloproliferation?

Features of myeloproliferation:

‒ Leucocytosis (WBC > 13 x109/L)‒ Monocytosis (monocytes >1 x109/L)‒ Thrombocytosis (plts. >450 x109/L)‒ Splenomegaly



Step 2: Are bone marrow blasts > 20%? yes AML


Step 4: What is the percentage of blasts?

yes MDS/MPN:CMMLaCMLMDS/MPN-U

CD34

significantdysgranulopiesis




Step 3: Features of myeloproliferation??


10% - 19% 5% - 9%< 5%

MDS-EB-1MDS-EB-2

yes AML








Step 5: What is the percentage of RS?

yes AML








Step 5: What is the percentage of RS?

< 15%

Multilineage dysplasia?2 or more cell lines with >10% dysplasia

≥ 15%

Multilineage dysplasia?2 or more cell lines with >10% dysplasia

MDS-SLD MDS-MLD

no yes no yes

MDS-RS-SLD MDS-RS-MLD

yes AML


MDS/MPN-RS-T


Multidisciplinary review ofdiagnostic features is an absoluterequirement to reach a consensus

diagnosis in MDS & MDS/MPN

Documents

Practical guidelines for diagnosing MDS and MDS/MPN … guidelines for diagnosing MDS and ... ring sideroblasts ... definitive diagnosis in some or even a majority of cases