Letters to the Editor
824
mechanisms of action, including direct effects on the viability,
growth, or survival of malignant cells, immunomodulation of
T and NK cells, alteration of cytokine production, blockade
of angiogenesis, and additional effects on the tumor microenvironment.12 Thus, the use of two agents with complementary
mechanisms of action may yield additive benefit.
In our study, among eight untreated patients with complex
karyotype, two patients did not respond and died rapidly of their
disease, four patients presented a transient response, but finally
relapsed in the absence of intensification, and the two patients
who were allografted after achieving a satisfactory response
remained in remission at last follow-up over a year after
transplantation. Side effects appeared acceptable and consisted
mainly of hematologic toxicity that required to be closely
monitored. These results should be compared with those of
conventional chemotherapy where efficacy is poor, with often
intolerable toxicity.
In conclusion, this association of lenalidomide and azacitidine may offer a possibility of remission with a tolerable toxicity.
For patients considered for an allogeneic HSCT, the use in firstline therapy of these novel strategies rather than ICT is an
interesting option, particularly in case of complex cytogenetics.
These results are very promising, and developing innovating
rational combinations seems to be a major step to improve the
treatment of high-risk myeloid malignancies.
Conflict of interest
2
3
4
5
6
7
8
The authors declare no conflict of interest.
E Scherman1,3, S Malak1,3, C Perot2, NC Gorin1,
MT Rubio1 and F Isnard1
1
Department of Hematology, Assistance Publique-Hopitaux
de Paris (AP-HP) Saint-Antoine, Universite
Pierre et Marie Curie, Paris, France and
2
Cytogenetic Laboratory, Assistance Publique-Hopitaux
de Paris (AP-HP) Saint-Antoine, Universite
Pierre et Marie Curie, Paris, France
E-mail: [email protected]
3
These authors contributed equally to this paper.
9
10
11
References
12
1 Grimwade D, Walker H, Oliver F, Wheatley K, Harrison C,
Harrison G et al. The importance of diagnostic cytogenetics on
outcome in AML: analysis of 1612 patients entered into
the MRC AML 10 trial. The Medical Research Council Adult
and Children’s Leukaemia Working Parties. Blood 1998; 92:
2322–2333.
Fenaux P, Mufti GJ, Hellstrom-Lindberg E, Santini V, Finelli C,
Giagounidis A et al. Efficacy of azacitidine compared with that of
conventional care regimens in the treatment of higher-risk
myelodysplastic syndromes: a randomised, open-label, phase III
study. Lancet Oncol 2009; 10: 223–232.
Maurillo L, Venditti A, Spagnoli A, Gaidano G, Ferrero D, Oliva E
et al. Azacitidine for the treatment of patients with acute myeloid
leukemia : Report of 82 patients enrolled in an italian compassionate program. Cancer; e-pub ahead of print 14 July 2011;
doi:10.1002/cncr.26354.
Fenaux P, Mufti GJ, Hellstrom-Lindberg E, Santini V, Gattermann
N, Germing U et al. Azacitidine prolongs overall survival
compared with conventional care regimens in elderly patients
with low bone marrow blast count acute myeloid leukemia. J Clin
Oncol 2009; 28: 562–569.
Itzykson R, Thepot S, Quesnel B, Dreyfus F, Beyne-Rauzy O,
Turlure P et al. Prognostic factors for response and overall survival
in 282 patients with higher-risk myelodysplastic syndromes treated
with azacitidine. Blood 2011; 117: 403–411.
List A, Dewald G, Bennett J, Giagounidis A, Raza A, Feldman E
et al. Lenalidomide in the myelodysplastic syndrome
with chromosome 5q deletion. N Engl J Med 2006; 355:
1456–1465.
Ades L, Boehrer S, Prebet T, Beyne-Rauzy O, Legros L, Ravoet C
et al. Efficacy and safety of lenalidomide in intermediate-2 or highrisk myelodysplastic syndromes with 5q deletion: results of a phase
2 study. Blood 2009; 113: 3947–3952.
Sekeres MA, List AF, Cuthbertson D, Paquette R, Ganetzky R,
Latham D et al. Phase I combination trial of lenalidomide and
azacitidine in patients with higher-risk myelodysplastic syndromes.
J Clin Oncol 2010; 28: 2253–2258.
Schmid C, Schleuning M, Ledderose G, Tischer J, Kolb HJ.
Sequential regimen of chemotherapy, reduced-intensity conditioning for allogeneic stem-cell transplantation, and prophylactic
donor lymphocyte transfusion in high-risk acute myeloid
leukemia and myelodysplastic syndrome. J Clin Oncol 2005; 23:
5675–5687.
Garcia-Manero G, Fenaux P. Hypomethylating agents and other
novel strategies in myelodysplastic syndromes. J Clin Oncol 2011;
29: 516–523.
Shen L, Kantarjian H, Guo Y, Lin E, Shan J, Huang X et al.
DNA methylation predicts survival and response to therapy in
patients with myelodysplastic syndromes. J Clin Oncol 2010; 28:
605–613.
Kotla V, Goel S, Nischal S, Heuck C, Vivek K, Das B et al.
Mechanism of action of lenalidomide in hematological
malignancies. J Hematol Oncol 2009; 2: 36.
Development of acute myeloid leukemia with NPM1 mutation, in Ph-negative clone,
during treatment of CML with imatinib
Leukemia (2012) 26, 824–826; doi:10.1038/leu.2011.280;
published online 11 October 2011
Chronic myeloid leukemia (CML) therapy with imatinib achieves
disease control in the vast majority of patients, especially in those
with early chronic-phase disease. Additional clonal chromosome
abnormalities (CCA) in Philadelphia-positive cells (CCA/ Ph þ )
are found in up to 10% of CML patients at diagnosis, and are
correlated with worse overall survival. According to European
Leukemia Net (ELN) 2009 criteria, CCA/Ph þ is considered a
marker of treatment failure when found during imatinib
Leukemia
treatment.1 CCA in Ph-negative cells (CCA/Ph) are rarely found
at CML diagnosis, but can be found in up to 8% of patients
receiving imatinib or second generation tyrosine kinase inhibitors (TKIs). Some CCA/Ph, especially monosomy 7 or del(7q),
predispose to myelodysplastic syndrome (MDS) or acute myeloid
leukemia (AML) development, whereas others (for example,
trisomy 8) are usually transient.2 There are reports of diploid
acute leukemias (AML and ALL (acute lymphoid leukemia))
developing in CML patients receiving imatinib, without CCA/
Ph, but with antecedent myelodysplastic features.3 Rare cases
of AML developing in imatinib-treated CML patients with
Letters to the Editor
825
recurrent cytogenetic aberrations in Ph cells also exist: one
case with t(8;21)(q22;q22) and one case with inv3(q21q26).4,5
Clonal hematopoiesis can also be observed in Ph cells with
different techniques (X-linked human androgen-receptor gene
assay and single-nucleotide polymorphism array analysis).6 We
report a CML patient who achieved complete cytogenetic and
molecular response receiving imatinib, and then developed AML
with normal karyotype and NPM1mut/FLT3-ITDneg. A 61-year-old
man, with a medical history of Chronic Obstructive Pulmonary
Disease (COPD), was diagnosed in November 2004 with Ph þ
(P210) chronic-phase CML, bone marrow cytogenetics: t(9;22)
(q34;q11)[20], and Hasford and Sokal low risk. He started
imatinib, 400 mg daily, and achieved complete hematological
response within 2 weeks, complete cytogenetic response at 6
months (June 2005) and complete molecular response at 12
months (November 2005). Full blood count, peripheral-blood
smear cell morphology and bone marrow cytogenetics performed every 6 months were always normal, while 3-monthly
BCR-ABL1 transcript levels were undetectable with real-time
quantitative (RQ)-PCR. In July 2009, the patient presented with
mild anemia and thrombocytopenia (Hb 10.5 g/dl, Plt 110 000/
ml), WBC 4400 (differential normal). Bone marrow aspiration
showed 23% blasts, myeloperoxidase positive (MPO þ ), immunophenotypes: CD13 þ , CD33 þ , CD15 þ , CD117 þ ,
MPO þ , HLA (human leukocyte antigen)-DR þ , CD34 (French
American British (FAB) classification: AML M2). Karyotype was
normal 46,XY[20] and BCR-ABL1 transcripts were undetectable
(RQ-PCR and nested PCR). PCR with dye-labeled primers
followed by capillary electrophoresis (Beckman Coulter CEQ8000, Fullerton, CA, USA) revealed mutated NPM1 (NPM1mut
type B, after sequencing analysis) without FLT3-ITD (NPM1mut/
FLT3-ITDnegFWHO 2008 classification provisional entity: AML
with mutated NPM1). Isocitrate dehydrogenase (IDH)1 and
IDH2 mutation screening (PCR and direct sequencing) revealed
no mutations in exon 4. NPM1mut transcript quantification
(RQ-PCR, NPM1mut QuantTM MQPP-05, Ipsogen, Marseille,
France) was performed at the time of AML diagnosis (bone
marrow), in three patient’s RNA stored samples (peripheral
blood) 12, 6 and 3 months preceding AML development, and in
three unmutated NPM1 samples (negative control); results were
confirmed twice and reported as NPM1mut transcripts per 104
ABL1 copies, as previously described.7 NPM1mut transcript levels
were 170 103/104 ABL1 copies at AML diagnosis, and
interestingly, 5.5 103, 7.9 103 and 59 103/104ABL1 copies
in the samples dated 12, 6 and 3 months before AML diagnosis,
respectively (see Figure 1). The patient had no HLA-matched
related donor, and in August 2009 after discontinuation of
imatinib, he received induction 2 þ 5 chemotherapy (idarubicin
12 mg/m2 d1–d2, cytarabine 200 mg/m2 d1–d5 continuous
infusion) and achieved complete remission. He subsequently
received 2 þ 5 consolidation therapy (same as above) and two
cycles of high-dose cytarabine (HiDAC, 1 g/m2 d1, d3, d5),
remaining off imatinib therapy. In August 2010, the AML
Table 1
relapsed with the same immunophenotype; normal karyotype,
NPM1mut/FLT3-ITDneg and BCR-ABL1 transcripts were undetectable. Screening for IDH mutations revealed IDH2 R140Q exon 4
heterozygous mutation. He received salvage chemotherapy with
Fludarabine ARA-C G-CSF Mitoxantrone (FLAG-N) regimen
(Fludarabine 30 mg/m2 d1–d5, ARA-C 1.5g/m2 d1–d5, Mitoxantrone 10 mg/m2 d1, d3, d5), achieved complete remission, and
subsequently FLAG-N consolidation chemotherapy (same as
above). RIC MUD allo-transplant was not performed because his
lung function was prohibitive. He relapsed once more in
February 2011, with the same immunophenotypic and molecular
markers (NPM1mut/FLT3-ITDneg/IDH2R140Q) but complex karyotype: 46,XY,t(1;12)(q42;q13)t(7;11)(p22;q23)[13]/46,idem,t(13;15)
(q34;q13)[2]/46,XY[11]. The patient is currently receiving supportive care. Table 1 shows patient’s different diseases, molecular
aberrations and karyotype over time. Clonal hematopoiesis in
Ph cells can be found in CML patients receiving TKIs during
routine bone marrow cytogenetics or after MDS-related changes
have occured (for example, unexplained anemia, neutropenia,
thrombocytopenia, dysplastic peripheral-blood smear morphology, increased MCV and so on). Most of these clones do not
seem to confer increased risk for progression to AML, whereas
other clones (such as monosomy 7 or del(7q)) do.2 The exact
number of CML patients developing AML in Ph clones during
TKI treatment is not known, but CCA/Ph have been described
in up to 8% of patients treated with imatinib.1 The causative role
of imatinib in Ph MDS/AML development is unknown. In vitro
experiments with varying imatinib concentrations on normal
human and animal fibroblasts showed that imatinib induced
centrosome and chromosome aberrations.8 In addition, rare
cases of MDS and AML have been recorded in gastrointestinal
stromal tumor (GIST) patients receiving imatinib, implying a
direct effect of TKIs in hematopoiesis. In contrast, CCA/Ph
have been described in IFN-a-treated CML patients, indicating
that some of these aberrations are not triggered by targeted
therapy.9 NPM1 mutation is considered a founder AML genetic
lesion, as it resides in the CD34 þ /CD38 leukemic stem cell
compartment. NPM1 mutations are found in chemotherapy
related AML (t-AML), but in a lower frequency compared with
de novo AML. Most of these NPM1mut t-AML have normal
karyotype, indicating a different pathogenesis from t-AML
Figure 1 Sequential measurement of NPM1mut transcript levels
before the development of AML.
Disease, molecular aberrations and karyotype over time
Date
Disease
Molecular aberration
Karyotype
November 2005
July 2009
August 2010
February 2011
CML diagnosis
AML diagnosis
AML 1st relapse
AML 2nd relapse
BCR-ABL1
NPM1mut/FLT3-ITDneg
NPM1mut/FLT3-ITDneg/IDH2R140Q
NPM1mut/FLT3-ITDneg/IDH2R140Q
46,XY,t(9;22)(q34;q11)[20]
46,XY[20]
46,XY[20]
46,XY,t(1;12)(q42;q13)t(7;11)(p22;q23)[13]/
46,idem,t(13;15)(q34;q13)[2]/46,XY[11]
Abbreviations: AML, acute myeloid leukemia; CML, chronic myeloid leukemia.
Leukemia
Letters to the Editor
826
with chromosomal abnormalities, and about half of them carry
FLT3-ITD. Chronic phase CML is NPM1wt, whereas only one
case of NPM1mut myeloid blast crisis CML has been reported.10
IDH1 and IDH2 mutations are also not found in chronic phase
CML but can be found at low frequency in blast crisis CML.11
Here, we present a CML patient who developed clonal hematopoietic disease (AML) in Ph cells, with normal karyotype and
NPM1mut, while being in complete CML molecular remission
and without previous MDS phase or CCA/Ph. The development of Ph AML could be the result of inherent genomic
instability or a direct effect of TKI therapy, whereas the
possibility that AML occurred by chance cannot be excluded.
It is should be stressed that sensitive RQ-PCR assay could detect
NPM1mut transcripts 1 year before overt AML, implying that the
development of NPM1mut AML was a slow process. He relapsed
twice with clonal evolution: IDH2 R140Q mutation at first
relapse and complex karyotype at second relapse. To our
knowledge, this is the first report of normal karyotype NPM1mut
AML in Ph cells in CML complete remission during imatinib
treatment.
2
3
4
5
6
7
Conflict of interest
The authors declare no conflict of interest.
G Georgiou1, A Efthymiou1, I Vardounioti1, G Boutsikas2,
MK Angelopoulou2, TP Vassilakopoulos2, M-C Kyrtsonis1,
E Plata2, P Tofas1, A Bitsani1, V Bartzi1, I Pessach1, M Dimou1
and P Panayiotidis1
1
Hematology Lab-1st Department of Propedeutic Medicine,
Laikon Hospital, Athens, Greece and
2
Hematology Clinic, Laikon Hospital, Athens, Greece
E-mail: [email protected]
8
9
10
References
11
1 Baccarani M, Cortes J, Pane F, Niederwieser D, Saglio G, Apperley J
et al. Chronic myeloid leukemia: an update of concepts and
management recommendations of European LeukemiaNet. J Clin
Oncol 2009; 27: 6041–6605.
Groves MJ, Sales M, Baker L, Griffiths M, Pratt N, Tauro S. Factors
influencing a second myeloid malignancy in patients with
Philadelphia-negative-7 or del(7q) clones during tyrosine kinase
inhibitor therapy for chronic myeloid leukemia. Cancer Genet
2011; 204: 39–44.
Pawarode A, Sait SN, Nganga A, Coignet LJ, Barcos M, Baer MR.
Acute myeloid leukemia developing during imatinib mesylate
therapy for chronic myeloid leukemia in the absence of new
cytogenetic abnormalities. Leuk Res 2007; 31: 1589–1592.
Schafhausen P, Dierlamm J, Bokemever C, Btuemmendorf TH,
Bacher U, Zander AR et al. Development of AML with
t(8;21)(q22;q22) and RUNX1-RUNX1T1 fusion following Philadelphia-negative clonal evolution during treatment of CML with
imatinib. Cancer Genet Cytogenet 2009; 189: 63–67.
Dvorak P, Hruba M, Subrt I. Development of acute myeloid
leukemia associated with Ph-negative clone with inv(3)(q21q26)
during imatinib therapy for chronic myeloid leukemia. Leuk Res
2009; 33: 860–861.
Paquette RL, Nicoll J, Chalukya M, Gondek L, Jasek M, Sawyers CL
et al. Clonal hematopoiesis in Philadelphia chromosome-negative
bone marrow cells of chronic myeloid leukemia patients receiving
dasatinib. Leuk Res 2010; 34: 708–713.
Kronke J, Schlenk RF, Jensen KO, Tschurtz F, Corbacioglu A,
Gaidzik VI et al. Monitoring of minimal residual disease in
NPM1-mutated acute myeloid leukemia: a study from the GermanAustrian acute myeloid leukemia study group. J Clin Oncol 2011;
29: 2709–2716.
Fabarius A, Giehl M, Frank O, Duesberg P, Hochhaus A,
Hehlmann R et al. Induction of centrosome and chromosome
aberrations by imatinib in vitro. Leukemia 2005; 19: 1573–1578.
Bacher U, Hochhaus A, Berger U, Hiddemann W, Hehlmann R,
Haferlach T et al. Clonal aberrations in Philadelphia chromosome
negative hematopoiesis in patients with chronic myeloid
leukemia treated with imatinib or interferon alpha. Leukemia
2005; 19: 460–463.
Piccaluga PP, Sabattini E, Bacci F, Agostinelli C, Righi S,
Salmi F et al. Cytoplasmic mutated nucleophosmin (NPM1) in
blast crisis of chronic myeloid leukaemia. Leukemia 2009;
23: 1370–1371.
Soverini S, Score J, Iacobucci I, Poerio A, Lonetti A, Gnani A et al.
IDH2 somatic mutations in chronic myeloid leukemia patients in
blast crisis. Leukemia 2011; 25: 178–181.
Extreme telomere erosion in ATM-mutated and 11q-deleted CLL patients is
independent of disease stage
Leukemia (2012) 26, 826–830; doi:10.1038/leu.2011.281;
published online 11 October 2011
Chronic lymphocytic leukaemia (CLL) is considered to arise
from a failure of apoptosis and an accumulation of
CD5 þ CD23 þ mature B-cells, although significant levels of
cell division underlie the clonal growth of these cells. This is
apparent from deuterated water incorporation experiments1 as
well as telomere erosion.2–4 We have recently shown that the
telomere erosion observed in CLL patients is extensive and can
result in the loss of telomere function resulting in telomere–
telomere fusion events, some of which were clonal;5 this work
also revealed telomeric loss of heterozygosity as well as largescale genomic rearrangements that were concomitant with
telomere dysfunction. Telomere dysfunction may therefore
account for clonal evolution and the occurrence of large-scale
genomic rearrangements, including the loss of 17p and 11q, that
Leukemia
confer a poor prognosis and are associated with short
telomeres.3 Short telomeres and telomeric DNA damage are
also associated with the development of resistance to DNA
damage-induced apoptosis.6 The telomere dynamics described
in CLL are indistinguishable from those observed experimentally
in fibroblast cells undergoing a telomere driven ‘crisis’ in culture
following the abrogation of the p53 pathway.5 In this situation,
the loss of cell cycle checkpoints in response to DNA doublestrand breaks (DSBs) facilitates the ongoing cell division beyond
the point that would normally trigger telomere-dependent
replicative senescence. It is clear from these in vitro studies
that there is a subtle distinction between the length of telomere
that elicits a cell cycle checkpoint response, triggering
p53-dependent replicative senescence or apoptosis and the
shorter telomeres that are capable of fusion in cells undergoing
‘crisis’.5 Based on these observations, we hypothesised that in
order for CLL cells to achieve substantial telomere erosion and
dysfunction they must be compromising in their ability to