2. INTRODUCTION
It is a MPN characterized by chromosomal translocation t(9;22)(q34.1;q11.2)
→ Philadelphia Chromosome (Ph) → BCR-ABL1 fusion gene
World wide, 1-2 cases per lac population, ↓ mortality with success of TKI therapy
Etiology is largely unknown, Acute Radiation Exposure
Three phases ; Chronic Phase, Accelerated Phase, Blast Phase
Insidious onset, ~50% asymptomatic, diagnosed on a routine medical examination
50% may have malaise, fatigue, palpable spleen
About 5% → AP or BP without recognized CP
3. CHRONIC PHASE
PERPHERAL BLOOD SMEAR
Leukocytosis: 12-1000x109
/L median~80 x109
/L
↑ Myelocytes and segmented neutrophils, no sig.
dysplasia
Blasts < 2%
Basophilia and Eosinophilia
Thrombocytosis: Normal -1000 x109
/L
PBS combined with cytogenetic studies for Ph chr.
Is diagnostic
BONE MARROW ASPIRATION
For karyotyping and confirmation of the stage of
disease
Hypercellular, expansion of myelocyte stage, no
sig. dysplasia, ↓ Erythroid precursors
Blasts usually <5% , ≥ 10% suggest advanced ds.
Megakaryocytes: N, slightly↓, in~50% ↑-
proliferation-small with hypersegmented nuclei
“Dwarf megakaryocytes”,
Pseudo-Goucher cells, ↑basophils and eosinophils
BM Biopsy
Done when findings in PBS are
atypical, or BM aspirate is
insufficient, LAYER OF IMMATURE
GRANULOCYTES IS 5-10 CELL THICK
NEAR THE BONE TRABECULAE
Reticulin fibrosis; ↑worst prognosis
no sig. in pts treated with TKI
4. ACCELERATED PHASE
Defining Criteria for Accelerated Phase of CML
CML-AP is defined by presence of ≥ 1of the following criteria
HEMATOLOGICAL CRITERIA
Persistent or increasing WBC Count( >10x 109/L) unresponsive to therapy
Persistent or increasing splenomegaly, unresponsive to therapy
Persistent Thrombocytosis (>1000x 109
/L), unresponsive to therapy
Persistent thrombocytopenia (<100 x109/L), unrelated to therapy
≥ 20% Basophils in the peripheral blood
10-19% Blasts in the peripheral blood and/or Bone Marrow
5. ACCELERATED PHASE
CYTOGENETIC CRITERIA
Additional clonal chromosomal abnormalities(Ph+) cells at diagnosis, including so called Major route
abnormalities( a second Ph chr., trisomy8, isochromosome17q,trisomy19), Complex karyotype and
abnormalities of 3q26.2
Any new chromosomal abnormality in Ph+ cells that occurs during therapy
PROVISIONAL RESPONSE TO TKI CRITERIA
Hematological resistance (or failure to achieve a complete hematological response) to first TKI
Any hematological, cytogenetic or molecular indications of resistance to sequential TKIs
Occurrence of two or more mutations in the BCR-ABL1 gene during TKI therapy
OTHRES; + Large clusters or sheets of abnormal megakaryocytes, marked Reticulin fibrosis in BMB
Lymphoblasts in PBS /BM (even if≤10%)— further clinical and genetic investigation
6. BLAST PHASE
≥ 20% Blasts in peripheral blood /Bone marrow
Presence of Extramedullary proliferation of blasts (CNS, Skin, Lung, LN)
Immunophenotyping
MYELOID BLASTS LYMPHOID BLASTS
Granulocytic, monocytic , erythroid TdT, B-cell CD19,CD10,CD79a,PAX5
Basophilic and megakaryocytic→ After introduction of TKI T-cell CD3,CD2,CD5,CD4,CD8 &CD7
(CD33,CD13,CD14,CD11b,CD11c,KIT,CD15,CD41
CD61,Glycophorin A&C and some lymphoid Ag)
Sequential Myeloblastic and Lymphoblastic BP have been reported
Heterogeneous blasts
7. PROGNOSIS AND PREDICTIVE FACTORS
Hematological Monitoring
Pathways affected: JAK/STAT,
PI3K/AKT, RAS/MEK, NF-KB
COMPLETE HEMATOLOGICAL
RESPONSE(CHR) ; WBC <10X 𝟏𝟎 𝟗
/L,
Platelet count <450x𝟏𝟎 𝟗
/L, No
immature granulocytes in PBS and
non palpable spleen
Cytogenetic Monitoring
t(9;22)(q34.1;q11.2)→p210(p230,p190),
Variant translocations, cryptic Ph, ACA: Extra
Ph,Iso.17q,chr.8+,9+
→Progression of AP to BP
→ Poor prognosis if present in CP
→Consider early stem cell transplantation
C CyR to first line TKI is 70-90% with 5 yr
prog. free survival and OS of 80-90%
Molecular monitoring
RT-PCR, RQ- PCR,
Major MR :BCR-ABL1<0.1% on
International scale
Deeper MR (BCR-ABL1 ≤0.01%)
achieved faster by second gen.
TKI
8. TIMING OF CYTOGENETIC AND MOLECULAR
MONITORING(ELN)
At diagnosis-
During Treatment-
Failure, Progression-
Warning-
CBA, FISH in case of Ph-(cryptic/variant translocations),qualitative PCR
(transcript type)
RQ-PCR every3 months until MMR has been achieved, then every3-6 months
and/or CBA at 3,6,12 months until C CyR is achieved, then every 12 months,
Once C CyR is achieved, FISH on blood cells can be used
RQ-PCR, mutational analysis, and CBA. Immunophenotyping in blast phase
Molecular and cytogenetic tests more frequently. CBA in case of or CCA/Ph-
9. European Leukemia Net Recommendations 2013 UPDATE
Response definitions for any TKI first line
Optimal Warning Failure
Baseline NA
High risk
Or
CCA/Ph+, major route
NA
3 months
BCR-ABL1 ≤10%
and/or
Ph+ ≤35%
BCR-ABL1 >10%
and/or
Ph+ 36-95%
Non-CHR
and/or
Ph+ >95%
6 months
BCR-ABL1 <1%
and/or
Ph+ 0
BCR-ABL1 1-10%
and/or
Ph+ 1-35%
BCR-ABL1 >10%
and/or
Ph+ >35%
12 months BCR-ABL1 ≤0.1% BCR-ABL1 >0.1-1%
BCR-ABL1 >1%
and/or
Ph+ >0
Then, and at any time BCR-ABL1 ≤0.1% CCA/Ph– (–7, or 7q–)
Loss of CHR
Loss of CCyR
Confirmed loss of MMR*
Mutations
CCA/Ph+
Definitions of the response to second-line therapy in
case of failure of imatinib
Optimal Warning Failure
Baseline NA
No CHR or loss of CHR on
imatinib or
lack of CyR to first-line TKI
or high risk
NA
3 months
BCR-ABL1 ≤10%
and/or
Ph+ < 65%
BCR-ABL1 >10%
and/or
Ph+ 65-95%
No CHR
or
Ph+ >95%
or new mutations
6 months
BCR-ABL1 ≤10%
and/or
Ph+ < 35%
Ph+ 35-65%
BCR-ABL1 >10%
and/or
Ph+ >65%
and/or new mutations
12 months
BCR-ABL1 <1%
and/or
Ph+ 0
BCR-ABL1 1-10%
and/or
Ph+ 1-35%
BCR-ABL1 >10%
and/or
Ph+ >35%
and/or new mutations
Then, and at any time BCR-ABL1 ≤0.1%
CCA/Ph– (–7 or 7q–)
or
BCR-ABL1 >0.1%
Loss of CHR
or
loss of CCyR or PCyR
New mutations
Confirmed loss of MMR*
CCA/Ph+
10. MUTATIONAL ANALYSIS
At diagnosis
Only in AP/BC patients
During first-line imatinib therapy
In case of failure
In case of an increase in BCR-ABL transcript levels leading to MMR loss
In any other case of suboptimal response
During second-line dasatinib or nilotinib therapy
In case of hematologic or cytogenetic failure
BLOOD, 4 AUGUST 2011 VOLUME 118, NUMBER 5
11. MUTATIONAL ANALYSIS
Summary of the most appropriate alternative therapeutic options based on the BCR-ABL KD mutation status
T315I
HSCT or investigational drugs
V299L, T315A, and F317L/V/I/C
Consider nilotinib rather than dasatinib
Y253H, E255K/V, and F359V/C/I
Consider dasatinib rather than nilotinib
Any other mutation
Consider high-dose imatinib* or dasatinib or nilotinib
HSCT indicates hematopoietic stem cell transplantation.
(BLOOD, 4 AUGUST 2011 VOLUME 118, NUMBER 5)
Methods: Direct sequencing, D-HPLC, Fluorescent allele specific-PCR
12. ATYPICAL CHRONIC MYELOID LEUKEMIA(aCML)
(Ph1-)
Diagnostic Criteria for BCR-ABL1-negative CML
Leukocytosis ≥ 13x 𝟏𝟎 𝟗
/L (↑ Neutrophils and their precursors)≥10% neutrophil prec.
Dysgranulopoeisis; (Abnormal Nuclear segmentation, chromatin clumping, hypogranularity, Acquired
Pelger-Huët anomaly
No or minimal abs. Basophilia <2% of peripheral blood leukocytes
No or minimal abs. Monocytosis <10% of peripheral blood leukocytes
Hypercellular BM granulocytic proliferation (M:E,>10:1) and granulocytic dysplasia with or without
dysplasia of erythroid and megakaryocytic lineage
< 20% blasts in blood and bone marrow
No evidence of PDGFRA,PDGFRB or FGFR1 rearrangement, or of PCM1-JAK2
WHO criteria of Ph+ CML, Primary myelofibrosis, PV,ET are not met.
13. aCML
Prognosis and predictive factors
Poor prognosis, median survival 14-29 months
Age> 65yr, Female, WBC count > 50x109
/L, Thrombocytopenia, Hb<10gm/dl→
Worst prognostic factors
Bone marrow transplant → Improved outcome
→ AML/ → Patients die of bone marrow failure
Genetic profile: chr8+,del(chr20q), abn.13,14,17,19,12
