Letters to the Editor
1618 Table 1
Patients’ characteristics and treatment outcome
Patient
1 2 3 4 5
Unique patient no. in Visani et al.3
Age
Status after induction+ consolidation
Intensification therapy
MRD before IFN-a
MRD after IFN-a
Time to MRD (months)
1 4 6 7 8
55 30 51 44 50
CR CR CR CR CR
CHT+IFN-a CHT+IFN-a ASCT+IFN-a ASCT+IFN-a ASCT+IFN-a
Positive Positive Positive Positive Negative
Negative Negative Negative Negative Negative
36 14 2 NAa NAb
Current status Molecular Molecular Molecular Molecular Molecular
CR CR CR CR CR
OS (months) 148 119 98 85 80
Abbreviations: ASCT, autologous stem cell transplantation; CHT, low-dose chemotherapy; CR, complete remission; IFN-a, interferon-a; MRD, minimal residual disease (evaluated by quantitative RT-PCR; negativity confirmed by nested PCR); NA, not applicable; OS, overall survival. a Patient no. 4 did not achieve molecular CR while on therapy with IFN-a only, but after imatinib addiction.7 b Patient no. 5 was already in molecular CR when received the first dose of IFN-a.
Acknowledgements This work was supported by European LeukemiaNet, COFIN 2002-2003 (Professor M Baccarani and SA Pileri), FIRB/RFO (Professor M Baccarani and SA Pileri), AIRC, Progetto Strategico di Ateneo 2006 (Dr Piccaluga), Fondazione CARISBO Bologna, Fondazione del Monte di Bologna e Ravenna. AIL Pesaro Onlus and BolognAIL grants.
PP Piccaluga1,5, G Martinelli1,5, A Isidori2, M Malagola3, M Rondoni4, S Paolini1, M Amabile1, I Iacobucci1, M Baccarani1 and G Visani2 1 Units of Hematology and Hematopathology, Department of Hematology and Oncological Science, ‘L and A Sera`gnoli’, S Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy; 2 Department of Hematology, S Salvatore Hospital, Pesaro, Italy; 3 Chair of Hematology, University of Brescia, Brescia, Italy and 4 Department of Hematology, Ravenna Hospital, Ravenna, Italy E-mail:
[email protected] 5 These two authors equally contributed to this work. References 1 Hoelzer D, Gokbuget N, Ottmann O, Pui CH, Relling MV, Appelbaum FR et al. Acute lymphoblastic leukemia. Hematology Am Soc Hematol Educ Program 2002, 162–192. 2 Piccaluga PP, Martinelli G, Rondoni M, Visani G, Baccarani M. Advances and potential treatment for Philadelphia chromosomepositive adult acute lymphoid leukaemia. Expert Opin Biol Ther 2006; 6: 1011–1022.
3 Visani G, Martinelli G, Piccaluga P, Tosi P, Amabile M, Pastano R et al. Alpha-interferon improves survival and remission duration in P-190BCR-ABL positive adult acute lymphoblastic leukemia. Leukemia 2000; 14: 22–27. 4 Zinzani PL, Bendandi M, Visani G, Gherlinzoni F, Frezza G, Merla E et al. Adult lymphoblastic lymphoma: clinical features and prognostic factors in 53 patients. Leuk Lymphoma 1996; 23: 577–582. 5 Amabile M, Giannini B, Testoni N, Montefusco V, Rosti G, Zardini C et al. Real-time quantification of different types of bcr-abl transcript in chronic myeloid leukemia. Haematologica 2001; 86: 252–259. 6 Gabert J, Beillard E, van der Velden VH, Bi W, Grimwade D, Pallisgaard N et al. Standardization and quality control studies of 0 real-time0 quantitative reverse transcriptase polymerase chain reaction of fusion gene transcripts for residual disease detection in leukemiaFa Europe Against Cancer program. Leukemia 2003; 17: 2318–2357. 7 Visani G, Isidori A, Malagola M, Alberti D, Capdeville R, Martinelli G et al. Efficacy of imatinib mesylate (STI571) in conjunction with alpha-interferon: long-term quantitative molecular remission in relapsed P-190(BCR-ABL)-positive acute lymphoblastic leukemia. Leukemia 2002; 16: 2159–2160. 8 Ottmann OG, Druker BJ, Sawyers CL, Goldman JM, Reiffers J, Silver RT et al. A phase 2 study of imatinib in patients with relapsed or refractory Philadelphia chromosome-positive acute lymphoid leukemias. Blood 2002; 100: 1965–1971. 9 Piccaluga PP, Paolini S, Martinelli G. Tyrosine kinase inhibitors for the treatment of Philadelphia chromosome-positive adult acute lymphoblastic leukemia. Cancer 2007; 110: 1178–1186. 10 Wassmann B, Scheuring U, Pfeifer H, Binckebanck A, Kabisch A, Lubbert M et al. Efficacy and safety of imatinib mesylate (Glivec) in combination with interferon-alpha (IFN-alpha) in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL). Leukemia 2003; 17: 1919–1924.
Successful peripheral blood stem cell mobilization with granulocyte colony-stimulating factor in a patient with chronic myeloid leukemia achieving a complete cytogenetic remission with dasatinib after failing imatinib
Leukemia (2008) 22, 1618–1619; doi:10.1038/leu.2008.13; published online 28 February 2008
Dasatinib is an orally active inhibitor of both ABL and SRC kinases, shown in both phase I and phase II clinical trials to be Leukemia
active in patients with chronic myeloid leukemia (CML) resistant to imatinib mesylate in all phases of the disease.1–4 Dasatinib induces complete cytogenetic responses (CCyR) in more than 40% of the patients treated after imatinib failure while in chronic phase (CP) irrespective of the presence of kinase domain (KD) mutations.4
Letters to the Editor
1619 A 30-year-old man presented elsewhere with CML-CP in 2002. He became intolerant of interferon-a and was commenced on imatinib mesylate at a dose of 400 mg daily. At 12 months he had failed to achieve a major CCyR (92% Philadelphia (Ph)-positive cells in the marrow) and imatinib was increased first to 600 mg and then to 800 mg per day. No response was seen after 4 months on the higher doses and the patient was referred to our center. Bone marrow cytogenetic analysis showed 100% Ph-positive metaphases with no additional abnormalities. BCR-ABL transcripts measured 47.8% by real-time quantitative (RQ)-PCR with ABL as control gene. Mutation analysis revealed an E453V (A1358T) KD mutation using direct sequencing; pyrosequencing confirmed that 75% of Ph-positive cells carried the mutation. This mutation has not been reported previously in patients treated with imatinib. The patient had no siblings and a suitable human lymphocyte antigen-matched donor could not be found. The patient was commenced on dasatinib 70 mg twice daily and achieved CCyR after 3 months of therapy. At 12 months the BCR-ABL/ABL ratio by RQ-PCR was 0.035% with no evidence of the mutation. In order to collect a Ph-negative stem cell population, we administered 10 mg kg1 of granulocyte colony-stimulating growth factor subcutaneously daily for 5 consecutive days. Dasatinib was continued throughout. On day 5, the peripheral blood CD34 þ ve cell count was 19.14 103 per ml (0.055% of total mononuclear cells). Apheresis was performed using COBE Spectra (version 4) (GambroRBCT) yielding a 141 ml product with a CD34 cell content of 1.37 106 per kg. A second apheresis procedure was carried out the following day resulting in a cell dose of 0.539 106 CD34 þ cells per kg in a 141 ml product. A total dose of 1.909 106 per kg CD34 þ cells was cryopreserved, which should be adequate for a conventional autograft. Cell viability was confirmed by Trypan blue (99.99%) and 7AAD (99.88%) techniques. Colony forming unit (CFU) analysis was within normal range (mean 26 105 MNC at day 14) with normal morphology. The BCR-ABL/ABL ratio was 0.091% in the harvested material. The E453V mutation was not detectable by pyrosequencing. The patient’s most recent
BCR-ABL/ABL ratio was 0.024% with no evidence on the mutant subclone. We have shown that is possible to mobilize and harvest adequate numbers of hematopoietic precursors in a patient responding to dasatinib with a very low level of contamination by leukemia as assessed by BCR-ABL transcripts. Furthermore, the previously detected E453V kinase mutation was absent in the harvested product. Dasatinib is highly effective in inducing CCyRs in patients after imatinib failure, but the durability of such responses has not yet been established. Thus it may be useful to harvest hematopoietic precursors at the nadir of leukemia cells in the body in patients, whose probability of remaining in remission is arguably lower than that of patients with a durable response to initial treatment with imatinib.
I Gabriel, A Chaidos, J Sorouri, E Dannie, J Davis, J Goldman, J Apperley and D Marin Department of Haematology, Hammersmith Hospital, London, UK E-mail:
[email protected] References 1 Talpaz M, Shah NP, Kantarjian H, Donato N, Nicoll J, Paquette R et al. Dasatinib in imatinib-resistant Philadelphia chromosomepositive leukemias. N Engl J Med 2006; 354: 2531–2541. 2 Guilhot F, Apperley J, Kim DW, Bullorsky EO, Baccarani M, Roboz GJ et al. Dasatinib induces significant hematologic and cytogenetic responses in patients with imatinib-resistant or -intolerant chronic myeloid leukemia in accelerated phase. Blood 2007; 109: 4143–4150. 3 Cortes J, Rousselot P, Kim DW, Ritchie E, Hamerschlak N, Coutre S et al. Dasatinib induces complete hematologic and cytogenetic responses in patients with imatinib-resistant or -intolerant chronic myeloid leukemia in blast crisis. Blood 2007; 109: 3207–3213. 4 Hochhaus A, Kantarjian HM, Baccarani M, Lipton JH, Apperley JF, Druker BJ et al. Dasatinib induces notable hematologic and cytogenetic responses in chronic-phase chronic myeloid leukemia after failure of imatinib therapy. Blood 2007; 109: 2303–2309.
BRAF mutations are very rare in B- and T-cell pediatric acute lymphoblastic leukemias
Leukemia (2008) 22, 1619–1621; doi:10.1038/leu.2008.14; published online 14 February 2008
We read with interest the study by Gustafsson et al.1 regarding BRAF mutations in childhood acute lymphoblastic leukemia (ALL). They investigated exons 11 and 15 of BRAF and exons 1 and 2 of NRAS in 29 cases (25 pre-B ALL, 3 T-cell ALL and 1 undifferentiated ALL), and identified six (21%) BRAF mutations and seven (24%) NRAS mutations. The frequencies of BRAF mutations seemed to be particularly common in T-cell ALL (two out of three; 67%); only four (16%) of the pre-B ALL harbored a BRAF mutation. All mutations were located in exon 15Fthree L597Q and one V590I among the pre-B ALL and one V600E and one G596S in the T-cell ALL. Hou et al.2 recently demonstrated that the L597Q mutation is a functional oncogene, at least in an in vitro experimental system. In the study by Gustafsson et al.,1 and as expected based on previous studies,3,4 the BRAF and NRAS mutations were generally mutually exclusive. The high
frequency of BRAF mutations was unexpected since such mutations otherwise have been demonstrated to be very rare in hematologic malignancies. In fact, previous analyses revealed no BRAF mutations in 53 cell lines from leukemias and lymphomas,3 65 multiple myelomas/plasma cell leukemias,5 21 multiple myelomas6 or in 149 acute myeloid leukemias (AML).7,8 We know of only three additional studies reporting acquired BRAF mutations in malignant hematologic disorders. In a series of 164 B- and T-cell lymphomas, Lee et al.9 detected BRAF mutations in B2.5%. The same group10 also reported such mutations in 20% of B-lineage ALL, 9% of acute biphenotypic leukemia and 4% of AML; all the investigated patients were adults. Finally, Christiansen et al.,11 who analyzed 140 treatment-related myelodysplastic syndromes and AML, found three t-AML with a BRAF mutation; all these were adult acute monoblastic leukemias with t(9;11)(p21;q23). Interestingly, germ line mutations in the closely related RAF1 (previously CRAF) were recently reported in two patients who developed t-AML.8 Hence, there may be an association between Leukemia
