A Case of Acute Lymphoblastic Leukemia with Eosinophilia.

Acute lymphoblastic leukemia with eosinophilia (ALL/E₀) is a rare clinical entity. Since Spitzer and Garson’s first description, only less than 100 cases have been reported. Here we report a 48-year-old man who was diagnosed with ALL/E₀ in our hospital. The patient presented with pitting edema at both his ankles on March 10, 2005. His complete blood cell counts at out patient clinic showed a WBC count of 39800/mm³ with 68% eosinophils. He was admitted. Abdominal examination showed an enlarged liver of 3cm and spleen of 4cm size, but no lymphadenopathy. No rash or purpuric patche was found. Total leucocyte count after admission was 411000/mm³ with 42% eosinophils. Platelet count was 80000/mm³, and hemoglobin was 115g/l. Bone marrow examination showed 70% blasts and 3% eosinophils, and was diagnosed as acute lymphoblastic leukemia of L₃ type. Flow cytometric immunophenotyping of these blasts showed expression of CD₁₀ (86.87%), CD₂₂ (96.68%), CD₇₉a (86.82%), and HLA-DR (92.59%). Cytogenetic analysis of the bone marrow showed a karyotype of 46, XY, del (1)(p32. There was no evidence of parasitic, viral or bacterial infection, drug reaction, allergic/immunologic disorder and other neoplastic disease. A diagnosis of ALL-E₀ was made and the patient was start on induction chemotherapy with vincristine (4 mg, d _1,8), daunomycin (70 mg, d _1~3), cyclophosphamide (1.0 g d₁, 0.6 g d₈) and prednisone (60 mg, d_1~14) on March 22. The eosinophils in the blood disappeared the same day after chemotherapy and the bone marrow examination on July 5 showed remission and the percentage of eosinophils was normal. Two more causes of VDCP and two additional courses of high dose arabinosyl cytosine were given, and he remains hematological remission. Eosinophilia can present before, concurrent with, or following the diagnosis of ALL. Several hypotheses seek to explain the hypereosinophilia in ALL. Il-3 plays an important role in the differentiation of the progenitor cells differentiating into mature eosinophils. In the specific cytogenetic abnormality t (5; 14)(q31; q32) and t (5; 9)(q31; p24), immunoglobulin heavy gene enhancer region joins to the promoter region of the IL-3 and JAK2 (9p24) gene, respectively, which causes high levels of IL-3 by leukaemic cells. In addition, when the purine and pyrimidine nucleotide content of the eosinophils in ALL-E₀ patients was compared with that of eosinophils from healthy donors and from patients with eosinophilia not associated with leukemia, the ratios of purine: pyrimidine and of uracil:cytosine nucleotides were decreased, while the total nucleotide concentration was increased, especially the concentration of UDP-sugars and pyrimidine nucleotides. Similar changes were also detected in leukemic cells of patients with ALL compared to normal lymphocytes. Thus, it has been suggested that the eosinophils in the patients with ALL-E₀ has a malignant character, and it might be an intrinsic part of the lymphoproliferative disorder and not a reaction to leukemic process. Patients with these this syndrome characteristically have cytogenetic abnormalities involving t(5;14), whereas our patient was found to have 46, XY, del(1)(p32). The prognosis of ALL- E₀ seems to be determined by the effect of the chemotherapy on ALL, complications of chemotherapy and hypereosinophilia. After having been diagnosed, our patient accepted three course of VDCP (vincristine, daunomycin, Cyclophosphamide and prednisone), two courses of high dose arabinosyl cytosine. He is still in hematological remission and is preparing for allogenetic hemopoietic stem cell transplantation.