Megakaryoblastic Leukemia and Down's Syndrome: A Review

Megakaryoblastic leukemia and transient leukemia in Down's syndrome have been reviewed using case reports from the literature and our own experience at the Hospital for Sick Children. The following conclusions have been reached: (1) approximately 20% of leukemia (excluding transient leukemia) in Down's syndrome is acute megakaryoblastic leukemia; (2) approximately 20% of all leukemia in Down's syndrome is transient leukemia; (3) transient leukemia in Down's syndrome is acute megakaryoblastic leukemia; (4) recurrence of acute megakaryoblastic leukemia occurs in 20% of the cases of transient leukemia; and (5) the incidence of acute megakaryoblastic leukemia in Down's syndrome is estimated to be 400 times that in normal children. These observations suggest that a specific form of leukemia, namely acute megakaryoblastic leukemia, has a remarkable association with Down's syndrome.     

Utility of 18-fluorodeoxyglucose positron emission tomography in children with relapsed/refractory leukemia

Abstract

Objective: Few data are available on the clinical significance of 18-fluorodeoxyglucose positron emission tomography (FDG-PET/CT) results in patients with leukemia. We investigated the utility of FDG-PET/CT at the time of relapsed/refractory disease in pediatric patients with leukemia. Methods: Medical records of 28 children with suspected leukemia progression or recurrence during/after chemotherapy or allogeneic stem cell transplantation (allo-SCT) were retrospectively reviewed to determine the utility of FDG-PET/CT. Results: Twenty-two of the 28 patients have documented abnormal imaging findings during clinical follow-up, while six had were interpreted as not demonstrating signal consistent with active leukemia. Of the 22 patients with abnormal FDG-PET/CT studies 14 were found to have FDG-PET/CT reported as consistent with active leukemia and increased leukemia blasts on bone marrow biopsy. Regarding the eight patients without positive FDG-PET/CT and proven leukemia relapse, four had discordant findings on FDG-PET/CT and biopsy, and four had FDG-PET/CT reported as infection. Mean maximum standardized uptake values (SUVmax) were significantly higher among patients whose FDG-PET/CT findings were positive for leukemia as opposed to infectious disease (p?<?.05). Mean SUVmax was also significantly higher among patients with multifocal lesions on FDG-PET/CT than among those with diffuse lesions (p?<?.05). Conclusions: The findings suggest that FDG-PET/CT may be a complementary imaging modality that could be combined with bone marrow examination to improve detection of subtle leukemic infiltration in children with suspected leukemia progression or recurrence after chemotherapy or allo-SCT.     

Intraventricular versus intralumbar methotrexate for central-nervous-system leukemia: Prolonged remission with the ommaya reservoir

Ten children had recurrence of central-nervous-system (CNS) leukemia despite monthly injections of methotrexate into their lumbar cerebrospinal fluid. Each child was then reinduced into remission and maintained with intraventricular methotrexate administered via an Ommaya reservoir and the length of this remission was compared with the duration of the child's previous intralumbar-treated remission. Of eight evaluable patients, seven had longer CNS remissions with intraventricular therapy than with intralumbar therapy (P < 0.02). The median CNS remission duration in all patients was 475 days with intraventricular and 286 days with intralumbar therapy (P < 0.05). The rate of CNS relapse was reduced from 2.94 relapses per thousand days at risk during intralumbar therapy to 0.93 relapse per thousand days of intraventricular therapy. We conclude that intraventricular chemotherapy is significantly more effective against CNS leukemia than the same therapy given by lumbar puncture.     

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??Although in recent years the effect of the treatment of leukemia is increasingly improved?? recurrence due to minimal residual disease??MRD?? is still a big problem. Recently the study on MRD detection in acute lymphoblastic leukemia is better?? but the research of MRD in other types of leukemia needs to be improved. There are two main techniques of MRD detection??molecular biology technique??such as PCR and molecular immunology technique??such as the flow cytometry ??FCM??. Clinicians should be aware of the progress in the detection of MRD in leukemia.     

NAD(P)H:quinone oxidoreductase 1 null genotype is not associated with pediatric de novo acute leukemia

BACKGROUND: NAD(P)H:quinone oxidoreductase1 (NQO1) is a two-electron reductase that detoxifies quinones derived from the oxidation of phenolic metabolites of benzene. Exposure to benzene metabolites increases the risk of hematotoxicity and leukemia. NQO1 enzyme activity protects the cells against metabolites of benzene. C to T base substitution at nucleotide 609 of NQO1 cDNA (C609T) results in loss of enzyme activity. Low NQO1 activity may play a role in etiology of acute leukemia. PROCEDURE: We analyzed NQO1 C609T gene polymorphism using the PCR-RFLP method in 273 patients with de novo acute leukemia (189 acute lymphoblastic leukemia (ALL), and 84 acute myeloid leukemia (AML) and 286 healthy volunteers to investigate the role of NQO1 polymorphism in the etiology of acute leukemia. RESULTS AND CONCLUSIONS: The frequency of homozygosity for NOQ1 C609T polymorphism was 3.5% in the healthy control population and 2.5% in pediatric acute leukemia. The NQO1 C609T allele frequency was not statistically different in the children with acute leukemia in comparison to the controls (odds ratio (OR), 0.76; 95% confidence interval (CI), 0.58-1.01; P = 0.06). The distribution of NQO1 genotypes among children with acute leukemia was not statistically different from the control group (P = 0.13). These findings do not support the role of NQO1 C609T polymorphism in the etiology of de novo pediatric acute leukemia.     

两种不同方案治疗儿童急性淋巴细胞白血病骨髓复发的临床观察

目的 回顾性分析两种不同再诱导方案治疗儿童急性淋巴细胞白血病（ALL）骨髓复发的短期疗效。方法 回顾性选择57例骨髓复发的ALL患儿为研究对象,根据治疗方案分为VMDP组（长春新碱+米托蒽醌+地塞米松+培门冬酰胺酶,n=42）和VIDP组（长春新碱+去甲氧柔红霉素+地塞米松+培门冬酰胺酶,n=15）。分析比较两组完全缓解率和不良反应发生率。结果 VMDP组和VIDP组完全缓解率（74% vs 73%）差异无统计学意义（P > 0.05）。所有患儿均发生3级或3级以上的血液学不良事件,VMDP组化疗相关病死率低于VIDP组（P < 0.05）。两组间感染发生率差异无统计学意义（P > 0.05）。结论 针对骨髓复发的儿童ALL,VMDP和VIDP再诱导方案均能获得较高的完全缓解率,且VMDP化疗方案引起的相关病死率更低,可作为儿童ALL骨髓复发再诱导方案的选择。     

Survival of childhood leukemia in Singapore

The objective of this study was to evaluate the treatment outcome of children with acute leukemias at a university hospital in Singapore. Between January 1988 and January 1994, 66 children were treated, comprising 13 cases of acute myeloid leukemia (AML) and 53 of acute lymphoblastic leukemia (ALL). The 2-year disease-free survival (DFS) was computed according to the Kaplan-Meier method. The results showed that the survival for AML was poor, with a 2-year DFS of only 30%. The major cause of death for AML was leukemia and leukemia-related complications, such as hemorrhage and severe infections. In contrast, a 62% 2-year DFS was achieved for ALL. It was found that marked hepatosplenomegaly (enlarged liver and/or spleen ≥10 cm below the costal margin) at presentation correlated with a significantly shortened survival in our patients with ALL. The major cause for treatment failure in ALL was recurrence of disease. We conclude that the DFS for our patients with ALL at 2 years was fair. The treatment results for AML were poor, but the numbers are too small to make any definite conclusions. © 1996 Wiley-Liss, Inc.     

树突状细胞与儿童急性淋巴细胞白血病免疫治疗进展

儿童急性淋巴细胞白血病(ALL)由于体内微小残留病(MRD)的存在常导致复发.树突状细胞(DC)能呈递肿瘤抗原,刺激机体免疫系统而发挥抗肿瘤作用,所以利用DC的免疫治疗方法清除患儿体内的MRD就成为研究的热点.该文就DC的特性、ALL患儿与DC相关的免疫逃逸机制以及DC在ALL免疫治疗中的应用作一综述.     

微小残留病变检测在儿童急性白血病中的应用

近年来,儿童急性白血病（AL）治疗效果随化疗方案的改进和危险分层治疗的引入取得很大进展。但微小残留病变（MRD）仍然是影响AL预后的一大难题。MRD水平影响化疗方案的选择、复发风险的分级,同时还可用于判断预后。目前检测MRD的方法主要有流式细胞术（FCM）和PCR。随着二代测序技术（NGS）的不断成熟与发展,其在MRD检测尤其在干细胞移植（SCT）后MRD检测方面扮演着重要角色。本文对微小残留病变检测在儿童急性白血病中的应用进行综述。     

Long-term survivors of acute lymphoblastic leukemia — risk of relapse after cessation of therapy

The results of cessation of therapy (COT) in 64 long-term survivors (disease-free survival of five years or more) of acute lymphoblastic leukemia (ALL) were analyzed to determine the incidence of relapse off therapy. Thirty-seven of the patients had intermittent central nervous system (CNS) prophylaxis. Total follow-up from diagnosis varied from 5.75 to 27.75 years. The median time off therapy was three years (range, 8 months to 26 years). Eighty-six percent (55/64) of the patients continue in their initial remission. Eight patients had relapse, and one patient had a morphologically different leukemia at recurrence. All the relapses occurred between five to eight years from diagnosis and the cumulative rate of relapse for this period was 0.14. There was no significant difference in the rate of relapse for those receiving CNS prophylaxis (0.08) versus those not receiving CNS prophylaxis (0.19). The difference in the relapse rates for boys (0.24) versus girls (0.04) was statistically significant (P=0.04). Isolated testicular relapse (ITR) was not seen in any of the 34 boys. The present study confirms the earlier observations by others that relapse is uncommon in ALL patients remaining in remission longer than seven to eight years. ALL patients treated with intermittent CNS prophylaxis administered throughout the period of maintenance chemotherapy appear to be at no greater risk for relapse off therapy than those treated with high-dose initial cranial irradiation and intrathecal methotrexate. The longer duration of therapy and the use of a repetitive reinduction regimen for maintainance seem to be associated with a decreased risk of ITR after discontinuation of therapy for boys and men. There appears to be a small but definite risk of “second” leukemia in the long-term survivors of leukemia.     

Presentation of acute promyelocytic leukemia as granulocytic sarcoma

Granulocytic sarcoma (GS) is a localized tumor composed of immature myeloid cells. This extramedullary tumor can present before, concurrent with or after the diagnosis of acute myeloid leukemia. GS is extremely uncommon in acute promyelocytic leukemia (APL). As a proportion of patients never develop systemic disease, correct and timely diagnosis may be rather difficult, but is a prerequisite for optimal outcome. GS should be considered in the differential diagnosis of children with unusual bone lesions. We describe a patient with GS who presented with symptoms mimicking osteomyelytis or rheumatoid disease.     

101例儿童急性髓细胞性白血病免疫表型与预后相关分析

目的探讨免疫表型对儿童急性髓细胞性白血病的预后价值。方法采用流式细胞术检测101例儿童急性髓细胞性白血病(AML)患儿相关免疫表型,分析免疫表型对完全缓解(CR)及无疾病生存期(DFS)的影响。结果CD34阴性组及CD34、HLA-DR同时阴性组一疗程CR率均明显高于非阴性组,差异有统计学意义(P=0.008,0.000);DFS的CD34阴性组,HLA-DR阴性组以及CD34和HLA-DR同时阴性组均明显高于非阴性组,差异有统计学意义(P=0.004,0.006,0.040),而CD14,CD15,CD7,CD19差异对CR和DFS均无统计学意义。结论免疫表型对评估AML患儿的预后有一定意义。     

儿童急性白血病淋巴细胞变化与化疗和感染相关性探讨

目的 分析儿童急性白血病化疗后外周血中淋巴细胞的变化,探讨淋巴细胞值异常与患儿继发免疫紊乱,导致感染及重症感染发生之间的关系。方法 急性淋巴细胞白血病(ALL)27例,急性髓性白血病(AML)9例,经化疗骨髓持续缓解(CCR)9-12个月和21-24个月,外周血白细胞≥4.0×109／L时,用流式细胞仪、单克隆抗体(美国BD公司)分别检测患儿外周血中CD3+、CD4+、CD8+、CD19+、CD16／56+细胞的百分数,进行统计分析。结果 1.随着化疗次数的增加,机体的免疫活性细胞会受到不同程度损害,T细胞亚群的比例明显失调,CD4+细胞百分数下降(P<0.01),CD8+细胞百分数上升(P<0.05),CD4+／CD8+细胞比值严重倒置(P<0.01),CD19+细胞百分数下降(P<0.05),临床上常见白血病患儿易感染和多发严重感染亦与此有关。2.CD16／56+标记的自然杀伤细胞并不随化疗次数增加而有变化(P>0.05),在白血病的治疗中有重要意义。3.AML外周血中CD3+、CD4+、CD8+、CD4+／CD8+、CD19+、CD16+／56+细胞百分数无改变(P>0.05)。结论 ALL患儿免疫活性细胞随着化疗次数的增加受到明显影响,有必要尽早进行免疫干预治疗,以提高患儿机体的免疫功能,以增强抗感染能力,恢复机体的免疫监督能力。对CD19+细胞减少,在感染发生时,给与丙种球蛋白,可减轻感染程度。     

两种不同方案治疗儿童急性淋巴细胞白血病疗效分析

目的：比较两种治疗方案对小儿急性淋巴细胞白血病(ALL)治疗的近期完全缓解率(CR)与持续完全缓解(CCR),探讨影响小儿ALL长期生存的有关因素。方法：根据化疗方案所用药物不同将44例患儿分为2组：一般化疗组(A组),诱导治疗采用VCP(长春新碱、环磷酰胺、强的松),庇护所预防使用二联鞘注(甲氨喋呤、地塞米松),维持治疗使用6 巯嘌呤与甲氨喋呤,加强强化用VCP及COAP(长春新碱、环磷酰胺、阿糖胞苷、强的松)交替;强烈化疗组(B组),按照1993年广西北海会议制定的小儿急性白血病诊疗建议进行序贯治疗,其中大剂量甲氨喋呤(HD-MTX)采用每次 1.5～2.0 g/m2及三联鞘注(甲氨喋呤、阿糖胞苷、地塞米松)。结果：两种方案经过4周治疗44例患儿均获CR,但达到CR的时间A组为(3.83±0.41)周,长于B组(3.00±0.82)周(P0.05)。结论：强烈化疗组不仅近期完全缓解所用时间短,而且在CCR及预防疾病复发上明显优于一般化疗组,虽然强烈化疗后合并各种感染的机会增多,但只要积极采取相应的预防措施,取得家长的密切配合可以使其发生率降低。     

SPONTANEOUS RESOLUTION OF A SINGLE LESION OF MYELOID LEUKEMIA CUTIS IN AN INFANT: Case Report and Discussion

Though infantile leukemia has a historically poor prognosis, there may be a subset of patients with cutaneous disease whose disease will resolve without therapy. The authors report a case of infantile leukemia cutis who presented with a single subcutaneous chloroma that spontaneously resolved over the course of several weeks and who remains without evidence of disease nearly two years later. After reviewing the literature of congenital leukemia cutis, the authors conclude that withholding chemotherapy in infants with cutaneous myeloid leukemia in the absence of known negative prognostic factors (MLL or BCR-ABL translocations) or progressive disease is clinically indicated.     

Prophylactic post‐transplant dasatinib administration in a pediatric patient with Philadelphia chromosome‐positive acute lymphoblastic leukemia

Philadelphia chromosome‐positive acute lymphoblastic leukemia has a poor prognosis, even in pediatric patients. Although imatinib‐containing chemotherapy can reportedly improve early event‐free survival, allogeneic hematopoietic stem cell transplantation is still considered to be the main curative treatment option. Dasatinib, a novel abl tyrosine kinase inhibitor, is being used for the treatment of relapsed or refractory Philadelphia chromosome‐positive acute lymphoblastic leukemia and is reported to have excellent efficacy. We used dasatinib after bone marrow transplantation prior to the anticipated relapse for the purpose of prophylaxis against relapse. After discontinuation of dasatinib administration, molecular remission has lasted for 7 months. Although preventive use of dasatinib is as yet uncommon, we consider that dasatinib may eradicate the minimal residual disease and prevent recurrence, and it is feasible to administer and appears to be safe. Further studies are needed to confirm our experience in this case.     

Minimal requirements for the diagnosis,classification, and evaluation of the treatment of childhood acute lymphoblastic leukemia (ALL) in the “BFM family” cooperative group

Minimal requirements and their rationale for the diagnosis and the response to treatment in childhood acute lymphoblastic leukemia (ALL) were defined in the recently instituted “BFM-Family”-Group, in which the German, Austrian, Dutch, Italian, Belgian, French and Hungarian childhood leukemia study groups cooperate. ALL is defined as ≥ 25% lymphoblasts in the bone marrow; for confirmation of the diagnosis and classification the criteria of the French-American-British (FAB) criteria are retained. For determination of the extent of the disease at diagnosis or relapse the criteria by the Rome Workshop [1986] are recommended: An obligatory panel of monoclonal antibodies for immunophenotyping was defined, as well as criteria for precursor B-ALL and T-ALL. Cytogenetic studies may support the diagnosis and subtyping, and are essential to identify certain patients with a high risk of treatment failure (f.i. t(9;22), t(4;11)). The role of molecular genetics for the diagnosis and the characterization of leukemia and the value of its clinical application needs further elucidation. Relapse was defined as recurrence of evident leukemia in the blood, bone marrow (≥ 25% lymphoblasts) or at any other site (to be confirmed by histological examination). Bone marrow involvement combined with extramedullary relapse was defined as ≥ 5% lymphoblasts in the bone marrow. © 1992 Wiley-Liss, Inc.     

Acute lymphocytic leukemia with microblastosis and near haploidy (26 chromosomes): A case report

A three-year-old acute lymphocytic leukemia (ALL) patient had a modal chromosome count of 26 in her bone marrow metaphases. The leukemia was “common” ALL by cytochemical and immunologic studies. Five other cases had been reported previously, and all have had a near haploidy varying from 26 to 32 chromosomes. Disomy of chromosomes 18 and 21 is a consistent feature of this disease. Severe hypodiploidy correlates with microblastosis requiring morphologic separation from non-neoplastic small lymphocytes.     

儿童急性髓系白血病靶向治疗进展

急性髓系白血病(AML)约占儿童急性白血病的15%~20%,虽然在危险度分级、分层化疗以及支持治疗等手段下AML的总体生存率较前升高,但是传统治疗下的临床疗效仍然有限,且在提高初治缓解率及减少缓解后复发方面存在局限性。近年来,随着精准医疗的不断发展,靶向治疗机制即包括AML相关信号通路的异常激活以及表观遗传修饰等研究不断深入,分子靶向药物可针对于特定的受体及目的基因等发挥作用,从而增加疗效和改善AML患者预后。