Imatinib-Induced Hypogammaglobulinemia in Children and Adolescents with Chronic Myeloid Leukemia

Abstract

Imatinib-induced tyrosine kinase inhibition extends beyond the BCR-ABL mutation, resulting in adverse effects. We evaluated hypogammaglobulinemia as a potential ‘off-target’ action of imatinib in children with CML. A cross-sectional, observational study was performed. Patients with CML in chronic phase, age <18-years at diagnosis, receiving imatinib for a duration exceeding 6-months were enrolled. Serum immunoglobulin G, A, and M were measured by end-point nephelometry. Thirty patients were enrolled. The mean age at diagnosis was 10.4?±?3.1?years (range: 5-18). The mean age at enrollment was 16.4?±?4.1?years (range: 9-23). The median dose of imatinib was 287.5?mg/m² (IQR: 267.3, 345.0). The median duration of imatinib-therapy was 6-years (IQR: 3.0, 10.3). The median (IQR) normalized levels of IgG, IgA, and IgM were 33.0% (IQR: ?12.8, 58.7), 28.1% (IQR: ?17.0, 90.1) and 15.9% (IQR: ?9.3, 40.5), respectively. The IgG, IgA, and IgM levels were reduced in 9 (30%), 8 (27%), and 10 (33%) patients, respectively. Five (17%) patients had pan-hypogammaglobulinemia. We suggest checking immunoglobulin levels in patients with CML receiving imatinib with recurrent/unusual infections.     

儿童急性髓系白血病的诊断与治疗

近年来,儿童ALL的远期疗效已经得到明显提高,长期无病生存率可达到80%以上.但是儿童急性髓系白血病(AML)的疗效仍不理想.欧美等发达国家推出一系列有效化疗方案.我国专家也结合以往的经验与国际研究进展,提出符合我国国情的儿童AML诊治方案.现结合相关文献资料,将上述国内外经典方案的内容详细列出,并指出各方案的特点与实际疗效,以供读者参考.希望通过努力探索和不断改进,以提高我国儿童AML的远期疗效.     

Juvenile Chronic Myeloid Leukemia: Oncogene Characterization

A 3 1/2-year-old female presented with thrombocytopenia and anemia. The bone marrow showed marked hemophagocytosis with an increase in macrophages. Over the next 2 months, there was a progressive de-differentiation of this monocytic population with the accumulation of blasts in the blood and bone marrow. The blasts had a normal 46XX karyotype and showed no fusion of the bcr and abl genes associated with Philadelphia chromosome positive leukemia. Intensive chemotherapy produced a transient hypoplastic state during which a bone marrow transplant was performed. The bone marrow after transplant again demonstrated a large population of macrophages. These cells continued to de-differentiate over the ensuing year up until the time of the patient's death. The mononuclear blast cell population was inducible toward monocytic maturation in tissue culture by low doses of ARA-c or daunorubicin. These mononuclear blasts expressed c-myc and c-fos mRNA at high levels, a further marker of their proliferative state and monocytic origin.     

Chronic Myeloid Leukemia in Children: Challenges and Opportunities

Treatment with tyrosine kinase inhibitors (TKI) is an effective therapy for children and adolescents with chronic phase of chronic myeloid leukemia (CML). For the majority of patients with CML in low- and middle-income countries (LMIC), imatinib is the TKI of choice for reasons of cost, availability, and experience. Children are exposed to therapy for a greater proportion of their lifetime as compared to adults. The adverse effects of prolonged administration of TKI is a subject of ongoing research, as more experience is collected. Therapy with TKI is currently considered to be life-long. Trials on stopping treatment are ongoing to explore if it may be feasible in selected patients, as reported in adults. Growth-failure is a concerning adverse effect. Currently, it seems unclear if the final height attained is within the expected range of the mid-parenteral height and growth standards. Whether the children will achieve a normal height at the end of their growth potential or remain below the predicted range is critical to decide if therapeutic interventions (E.g., growth hormone therapy, or interruption in TKI) should be considered during the period of growth potential. Research on CML in children is at a relatively slow pace, largely due to the rarity of the disease. This provides a unique opportunity for research in population-dense LMICs, as several tertiary centers tend to have a sizable cohort of children and adolescents with CML on follow-up. This narrative summarises the challenges and opportunities in dealing with CML in children, particularly in reference to a center in LMIC.     

Malignant Osteopetrosis Manifested as Juvenile Chronic Myeloid Leukemia

Juvenile chronic myelogenous leukemia (JCML) is a clonal panmyelopathy associated with an elevated leukocyte count with a relatively high proportion of myelomonoblasts, normoblasts, lymphocytes and monocytes, splenomegaly, and a decreased or normal LAP score. Bone marrow shows erythroid and myeloid hyperplasia. JCML is distinguished from adult chronic myelogenous leukemia (CML), both clinically and by laboratory tests. Clinically, the patients suffer from typical rashes, organomegaly, including the liver, spleen and lymph nodes, bleeding phenomena, and a relatively rapid course. The typical laboratory findings are elevated fetal hemoglobin, immunodeficiency, thrombocytopenia, and leukocytosis with prominent involvement of the monocytic series and an absence of Ph chromosome or bor rearrangement.¹,² A selective increased response to granulocyte macrophage colony stimulating factor (GM-CSF) by hematopoietic cells appears to be involved in the pathogenesis of the disease.³     

Monosomy 7, Diabetes Insipidus and Acute Myeloid Leukemia in Childhood

The triad of diabetes insipidus (DI), monosomy 7, and acute myeloid leukemia in a 7—year old boy is described. This triad has been described in adults but not in children. The DI ran a transient, self-limiting course and required no specific therapy. The pathogenesis of DI remains unknown, and its transient nature may result in this component of the triad going unnoticed.     

Pseudo-Chediak-Higashi Anomaly in Acute Myeloid Leukemia (M2) of Childhood

The frequency and clinical significance of the pseudo-Chediak-Higashi (PCH) anomaly were studied in 20 children with acute myeloid leukemia (AML) M2 in the FAB nomenclature. PCH granules were recognized as giant eosinophilic granules, measuring up to 5μ, in the cytoplasm of leukemic cells on smears. At the electron microscope level, most PCH granules were round to oval and outlined by a limiting membrane, and contained homogeneous, granular, crystalloid, rod-like or myelin-like materials. The PCH anomaly was demonstrable in five (25.0%) of the 20 patients, which indicates that the anomaly is not rare in childhood AML M2. There were no differences between PCH anomaly-positive and PCH anomaly negative groups with regard to hepatosplenomegaly, hemoglobin levels, white blood cell counts, bone marrow cellularity, t(8q-, 21q+) chromosome abnormalities or prognoses. Circulating leukemic cells were observed less frequently in the PCH anomaly-positive group than in the PCH anomaly-negative group (p <0.05); the leukemic cells were not demonstrable in three of the five patients in the former group, although they were detected in all 15 patients in the latter group. The existence of PCH granules and/or a defect of the cytoskeleton responsible for the PCH anomaly in leukemic cells may impede their movement from the bone marrow to the peripheral blood.     

急性髓细胞性白血病患儿淋巴系分化抗原表达的意义

目的探讨淋巴系抗原在儿童急性髓细胞性白血病(AML)细胞中的表达及其临床意义。方法选择华中科技大学同济医学院附属同济医院儿科2000年1月-2009年7月收治的初诊AML患儿42例。其中原粒细胞白血病未分化型(M1)2例,急性髓细胞性白血病(M2)17例,颗粒增多的早幼粒细胞白血病(M3)12例,急性粒单核细胞白血病(M4)4例,急性单核细胞白血病(M5)7例。采用CD45/SSC双参数散点图设门方法对42例AML患儿进行三色流式细胞术细胞免疫分型检测。同时对伴淋巴系相关抗原表达的AML(Ly+AML)患儿与不伴淋巴系相关抗原表达的AML(Ly-AML)患儿的临床资料进行比较分析。结果42例AML患儿中13例伴有淋巴系抗原的阳性表达(30.95%),其中CD19在AML中的阳性表达率最高(33.33%),其次为CD7(11.90%)、CD3(11.90%)。CD19在M5中的阳性表达率为71.43%。Ly+AML组肝大例数与Ly-AML比较有统计学差异(χ2=6.48,P<0.05),其余临床指标均无统计学差异。Ly+AML组与Ly-AML组首次化疗后完全缓解率比较无差异。结论儿童AML伴有淋巴系抗原CD19...     

Chronic Myeloid Leukemia (CML) in Children: Classical and Newer Therapeutic Approaches

Chronic myeloid leukemia (CML) represents a rare myeloproliferative disease among children where allogeneic stem cell transplantation (SCT) remains the curative gold standard. However, the impressive early cytogenetic and molecular responses achieved by tyrosine kinase inhibitors [TKIs (imatinib, nilotinib, and dasatinib)] as first-line or even sole treatment in adults, has led to their increasing use also among children. Due to limited data regarding long-term results of TKIs and especially those of second generation in pediatric cohorts, we would like to add clinical information in this rare series of patients by reporting on four children with CML over a 10-year period, focusing on TKIs, dose escalations and clinical responses.     

T-Lymphocytes in Childhood Leukemia

The recent decade is associated with major breakthroughs in lymphocyte immunotyping. In view of the excellent improvement in chemotherapy results in acute lymphoblastic leukemia (ALL) and the chemotherapy associated mortality, Dr. Lovat and associates studied serially the T-lymphocytes in childhood leukemia¹.