Epidemiological evaluation and survival of children with acute myeloid leukemia

Abstract Objective: This study aims to describe the epidemiological characteristics and survival rates of children with acute myeloid leukemia treated in hospitals in southern Brazil and compare them with international data. Methods: A multicenter cohort study was conducted with retrospective data collection of all new patients with acute myeloid leukemia under 18 treated at five referral centers in pediatric hematology-oncology in southern Brazil between January 2005 and December 2015. Results: Of the 149 patients with acute myeloid leukemia, 63.0% (n = 94) were male. The median age at diagnosis was 10.5 years (range 0-18 years) and 40.3% (n = 60) had a white blood cell count below 50,000/mm2. The most common Franco-American-British (FAB) subtype was M3 (n = 43, 28.9%). Nine (6.0%) patients had central nervous system disease. In M3 patients, overall survival (OS) was 69.2% and 3-year event-free survival was 67.7%; in non-M3 patients, these rates were 45.3% and 36.7%, respectively. In non-M3 patients, OS was significantly different between transplanted (61.8%) and non-transplanted (38.2%) patients (p = 0.031). Conclusions: These results show a higher prevalence of the Franco-American-British M3 subtype than that reported in the international literature, as well as a decreased OS compared with that of developed countries. Further multicenter Brazilian studies with a larger sample size are encouraged to better understand the characteristics of acute myeloid leukemia, and to improve the treatment and prognosis in this population.

Panmielosis aguda con mielofibrosis / Acute panmyelosis with myelofibrosis

La panmielosis aguda con mielofibrosis (PMAF) es un raro desorden hematológico, definido como un subtipo de leucemia aguda. Se reporta un paciente masculino de 31 años de edad con historia de decaimiento marcado, fiebre vespertina y gingivorragia. El examen físico muestra palidez cutáneo mucosas, esplenomegalia ligera y en exámenes complementarios pancitopenia con 5 por ciento de blastos. En el medulograma no se obtuvo material y la impronta sugiere leucemia mieloide aguda no promielocítica. El estudio de inmunofenotipo por citometría de flujo confirma incremento de mieloblastos positivo para (CD34, CD13, CD17, CD117, CD38) y disminuidos en (CD11c y HLA-DR), con una mielofibrosis marcada en biopsia de medula ósea sin la presencia de blastos. Recibe tratamiento de inducción con esquema 3 + 7 (Citosar + Rubidomicina) después del cual el paciente se encuentra en remisión hematológica con persistencia de la fibrosis medular. Posteriormente inicia tratamiento con lenalidomida, Bifosfonatos (Ácido Zoledronico) y se encuentra en remisión hematológica 11 meses después del diagnóstico, hasta marzo 2020. Se realizan estudios de histocompatibilidad (HLA) para trasplante alogénico(AU)

Acute panmyelosis with myelofibrosis (PMAF) is a rare hematologic disorder, defined as a subtype of acute leukemia. A 31-year-old male patient with a history of marked decay, evening fever, and gingivorrhagia is reported. The physical examination showed mucous skin paleness, slight splenomegaly and the complementary examinations showed pancytopenia with 5 percent blasts. In the medullogram no material was obtained and the imprint suggests non-promyelocytic acute myeloid leukemia. Immunophenotype study by flow cytometry confirmed an increase in myeloblasts positive for (CD34, CD13, CD17, CD117, CD38) and decreased in (CD11c and HLA-DR), with marked myelofibrosis in bone marrow biopsy without the presence of blasts. He received induction treatment with a 3 + 7 scheme (Citosar + Rubidomycin) after which the patient was in hematological remission with persistence of spinal fibrosis. Later, he started treatment with lenalidomide, bisphosphonates (Zoledronic Acid) and was in hematological remission 11 months after diagnosis, until March 2020. Histocompatibility studies (HLA) were performed for allogeneic transplantation(AU)

Mejoría en la supervivencia de los niños con leucemia mieloide aguda en el Instituto Nacional de Cancerología de Colombia / Improvement in the survival of children with acute myeloid leukemia at the Colombian National Cancer Institute

Resumen Objetivo: Describir las características demográficas y clínicas de los pacientes con leucemia mieloide aguda (LMA) no promielocítica, y evaluar la mortalidad y la supervivencia de los niños tratados con protocolo LMA-INC 2004 (modificado de BFM 93) en la clínica de oncología pediátrica del Instituto Nacional de Cancerología, desde su instauración y por un periodo de 10 años y medio de seguimiento (mayo de 2004 a diciembre de 2014). Pacientes y método: Estudio observacional descriptivo retrospectivo de una cohorte con análisis de supervivencia de los pacientes menores de 18 años de edad con diagnóstico LMA tratados con quimioterapia intensiva sin mantenimiento ni trasplante. El análisis de supervivencia se realizó usando el método de Kaplan Meir. Resultados: Se analizaron 41 pacientes con diagnóstico de LMA excepto LMA M3, tratados con protocolo LMA-INC 2004. Se logró remisión completa en el 75,6% de los pacientes. La tasa de recaída fue de 27,4% anual y la tasa de muertes de 20,3% durante el periodo. La supervivencia general acumulada a dos años fue de 60% y a cinco años del 53,5%, con promedio de seguimiento de 4,3 años (3,2 - 5,2 años), y la supervivencia libre de recaída a cinco años fue del 42% con un tiempo promedio de seguimiento de 3,5 años (3,3 - 4,6 años). Conclusión: Los resultados muestran mejoría del 30% en la supervivencia de los pacientes con LMA como resultado de un tratamiento más intenso, que incluye la administración de altas dosis de citarabina y mitoxantrone en la consolidación y la intensificación, y que implica mejoría en los cuidados de soporte.

Abstract Objective: To describe the demographic and clinical characteristics of patients with acute myeloid leukemia; and to evaluate the mortality and survival of children treated with the LMA-INC 2004 protocol (modified from BFM 93) in a pediatric oncology clinic of the Colombian National Cancer Institute (Instituto Nacional de Cancerología de Colombia) between May 2004 and December 2014. Patients and methods: Retrospective descriptive observational study of a cohort with survival analysis of patients aged under 18 years, with a diagnosis of acute myeloid leukemia, who were treated with intensive chemotherapy without maintenance or transplantation. The survival analysis was performed using the Kaplan-Meier method. Results: We analyzed 41 patients diagnosed with myeloid leukemia, except acute myeloid leukemia type M3, who were, treated with the LMA-INC 2004 protocol. Complete remission was achieved in 75.6% of patients. The annual relapse rate was 27.4%; and the death rate 20.3%. Cumulative overall survival at 2 and 5 years was 60% and 53.5% respectively, with an average follow-up of 4.3 years (3.2 - 5.2 years); and the 5-year relapse-free survival was 42%, with an average follow-up time of 3.5 years (3.3 - 4.6 years). Conclusion: The results showed a 30% improvement in the survival of patients with acute myeloid leukemia, attributed to a more intense treatment that included the administration of high doses of cytarabine and mitoxantrone in consolidation and intensification; which implies improvement in supportive care.

Leucemia mieloide aguda: avaliação citogenética e implicação prognóstica ­ revisão de casos atendidos em Hospital Geral do Rio Grande do Sul / Acute myeloid leukemia: cytogenetic evaluation and prognostic implication ­ a review of the cases seen at a General Hospital of Rio Grande do Sul

Introdução: Análise do perfil citogenético de pacientes com Leucemia mieloide aguda (LMA) e correlação com dados clínico-epidemiológicos e seus respectivos prognósticos. Métodos: Busca de registros nos prontuários de pacientes com diagnóstico de LMA no período de janeiro de 2009 a dezembro de 2014. Mensurou-se o perfil citogenético da amostra, estratificando-a por faixa etária e classificação conforme FAB e OMS para posterior correlação dos dados de prognóstico e distribuição epidemiológica obtidos com os dados disponíveis na literatura médica atual. Resultados: Foram selecionados 38 pacientes para análise, com idades entre 1 e 84 anos. Todos os pacientes possuíam cariotipagem e 76,3% apresentavam alterações citogenéticas; 13 pacientes apresentavam cariótipo favorável (CF), 14, cariótipo intermediário (CI), 10, cariótipo desfavorável (CD) e 1 apresentava LMA secundária. No grupo com CF, a média de idade foi de 25 anos (p=0,0151); no grupo com CD, foi de 39,8%. No grupo com CF, 69,2% obtiveram remissão completa com protocolo de tratamento; no grupo com CI, 18,18% obtiveram a remissão completa, e por fim, no grupo com CD nenhum caso obteve remissão completa. Houve tendência à plaquetopenia mais significativa no grupo com CI. Conclusão: Ficou nítida a correlação das alterações citogenéticas observadas com sua respectiva importância prognóstica, corroborando a necessidade da determinação do cariótipo para o adequado manejo dos pacientes com LMA (AU)

Introduction: An analysis of the cytogenetic profile of patients with acute myeloid leukemia (AML) and correlation with clinical and epidemiological data and their respective prognoses. Methods: Search of records in the medical charts of patients diagnosed with AML from January 2009 to December 2014. The cytogenetic profile of the sample was measured by stratifying it by age group and classification according to FAB and WHO for subsequent correlation of prognostic and epidemiological distribution data obtained from the available data of the medical literature. Results: Thirty-eight patients were selected for analysis, ranging from 1 to 84 years of age. All patients had karyotyping and 76.3% presented cytogenetic alterations; 13 patients had favorable karyotype (FK), 14 intermediate karyotype (IK), 10 unfavorable karyotype (UK), and 1 had secondary AML. In the FK group, the mean age was 25 years (p = 0.0151); in the UK group, 39.8%. In the FK group, 69.2% achieved complete remission with treatment protocol; in the IK group, 18.18% had complete remission, and finally, in the UK group, no case achieved complete remission. There was a trend towards more significant thrombocytopenia in the IK group. Conclusion: The correlation of the observed cytogenetic changes with their respective prognostic importance was clear, corroborating the need to determine the karyotype for an adequate management of patients with AML (AU)

Regulatory T Cells in Egyptian Acute Myeloid Leukemia Patients.

Introduction: Current treatments for AML have not changed for several decades and have not resulted in satisfactory outcomes. Modulating the immune system may improve survival in AML patient. Increasing evidence shows that Treg cell may play an important role in immune evasion mechanisms employed by cancer Th is work was designed to measure the frequency of regulatory cells T cells (Treg(in newly diagnosed adult acute myeloid leukemia patients (AML) and to correlate its percent with cytogenetic study and clinical outcome. Material and methods: Th is study was conducted on 50 subjects divided into two groups: 25 AML cases(group 1) admitted to Hematology Unit, Alexandria Main University Hospital, Egypt and 25 healthy subjects(group 2) of matched age and sex. Detection of Treg was done to both groups by Multi-Color Flow Cytometry Kit. Results: Treg value was higher in AML patients at diagnosis compared to healthy controls. No signifi cant diff erence was present in the percent of Treg between the patients with normal and abnormal karyotype. Patients who achieved complete response after induction chemotherapy had lower Treg percent compared to those with persistent leukemia. Conclusion: From this study we can conclude that higher pretreatment Treg percentage may be a poor predictor to response to induction therapy.

NRAS Mutations in de novo acute leukemia: Prevalence and clinical significance.

The activating mutations of the Ras gene or other abnormalities in Ras signaling pathway lead to uncontrolled growth factor-independent proliferation of hematopoietic progenitors. Oncogenic mutations in NRAS gene have been observed with variable prevalence in hematopoietic malignancies. In the present study, NRAS mutations were detected using bidirectional sequencing in 264 acute leukemia cases — 129 acute lymphocytic leukemia (ALL) and 135 acute myeloid leukemia (AML) and 245 age- and gender-matched controls. Missense mutation was observed only in the 12th codon of NRAS gene in 4.7% of AML and 3.16% of ALL cases. The presence of NRAS mutation did not significantly influence blast % and lactate dehydrogenase (LDH) levels in AML patients. When the data were analyzed with respect to clinical variables, the total leukocyte count was elevated for mutation positive group, compared to negative group. In AML patients with NRAS mutations, 60% failed to achieve complete remission (CR), as compared to 34.8% in mutation negative group. These results indicated that NRAS mutations might confer poor drug response. In AML, disease free survival (DFS) in NRAS mutation positive group was lesser, compared to mutation negative group (9.5 months vs. 11.68 months). In ALL patients, DFS of NRAS mutation positive group was lesser than mutation negative group (9.2 months vs. 27.5 months). The CR rate was also lower for mutation-positive patients group, compared to mutation-negative group. In conclusion, these results suggested that presence of NRAS mutation at 12th codon was associated with poor response and poorer DFS in both ALL and AML.

Tratamiento de la leucemia mieloide aguda del niño en Cuba / Treatment of children acute myeloid leukemia in Cuba

Introducción: la leucemia mieloide aguda representa alrededor del 20 por ciento de las leucemias agudas de la niñez con una respuesta al tratamiento y supervivencia menores que la leucemia linfoide aguda. Objetivo: describir los resultados obtenidos con el tratamiento de la leucemia mieloide aguda del niño en algunos centros de Cuba en el período 2000-2008. Métodos: se trataron 46 pacientes con leucemia mieloide aguda, se excluyeron los casos con leucemia promielocítica, diagnosticados a partir del año 2000 en las provincias occidentales, Sancti Spíritus y Villa Clara. Se aplicaron dos esquemas de tratamiento tipo BFM en dos períodos: en el primero (2000 -2003) se incluyeron 27 enfermos y en el segundo (2004-2008), 19. La diferencia fundamental entre los dos períodos consistió en la consolidación que en la segunda etapa fue de ciclos más intensos y cortos. Resultados: predominó el sexo masculino (n = 32) y la mediana de edad fue de 9 años. La remisión inicial fue del 71 por ciento en la primera etapa y 89 por ciento en la segunda. La supervivencia libre de eventos (SLE) en todos los pacientes fue del 40 por ciento a los 5 años y la supervivencia global (SV) fue del 44 por ciento en igual período. En la SLE en las dos etapas se encontraron diferencias significativas siendo mayor en la segunda. En los años comprendidos entre el 2000 y el 2003 la SV a los 5 años fue del 31 porciento, mientras que entre 2004 y 2008 fue del 63 por ciento. No se empleó el trasplante de células progenitoras hematopoyéticas de forma sistemática. Conclusiones: estos resultados muestran un nivel comparable a los alcanzados a internacionalmente, lo que representa un importante logro del Sistema Nacional de Salud de Cuba

Introduction. acute myeloid leukemia represents about 20 percent of all leukemias in childhood with results and survival smaller than in acute lymphoid leukemia. Objectives: to describe the results obtained with the treatment of acute myeloid leukemia in children in some Cuban centers in from 2000 to 2008. Methods: forty-six patients from Western provinces of Cuba including Sancti Spiritus and Villa Clara were treated. The majority of the patients were males. The median age was 9 years old. Two periods of treatment were applied, the first from 2000 to 2003 with 27 patients; and the second from 2004 to 2008 with 19 cases. The difference between the two periods was that in the second one the consolidation had short and intensive cycles. Results: the initial remission was 71 percent in the first period and 89 percent in the second. Free survival was 40 percent in 5 years and the overall survival (OS) was 44 percent, but in the first period the OS was 30,8 percent and in the second it was 63,2 percent. Immunophenotype and cytogenetic and molecular alterations were studied only in 10 children. Hematopoietic transplantation was not performed sytematically. Conclusions: these results show a level comparable to those achieved internationally, representing a major achievement of the Cuban National Health System

Clinical manifestations of acute myeloid leukemia

Acute myeloid leukemias [AML] affect preferentially adults. Clinical manifestations are due to cytopenias and tissue infiltration. Manifestations vary with certain subtypes e.g. bleeding and infections are common with AML-M3, tissue infiltration is more often seen in AML-4 and M5, and bone marrow fibrosis is seen in AML-M7. To study demographic features and clinical manifestations of acute myeloid leukemia. Patients and A cross-sectional study was conducted at department of Pathology, Pakistan Institute of Medical sciences, Islamabad from July 2007 to July 2009. All the cases of AML [diagnosed on bone marrow biopsy] belonging to all age groups and both sexes were included in the study. Age at diagnosis, symptoms and clinical findings in AML and its various subtypes were noted. Results were entered on SPSS version 14 for statistical analysis. In a total of 82 cases of AML, 55% were males and 45% females, with mean age of 27.5 +/- 19.9 years SD. The most common subtype was AML-M1 [33%] followed by M3 [22%] and M4 [18%], respectively. The common presenting symptoms were pallor, fever and bleeding. Hepatomegaly, splenomegaly, lymphadenopathy and gum hyperplasia were also frequent. Tissue infiltration was the commonest in AML-M5 and M4. Acute myeloid leukemia is the malignancy of adults; it is more common in males and manifestations vary with its subtype

Leucemia mieloide aguda versus ocupação profissional: perfil dos trabalhadores atendidos no Hospital de Hematologia de Recife / Acute myeloid leukemia versus professional occupation: the profile of workers treated at the Recife Hematology Hospital / Leucemia mieloide aguda versus ocupación profesional: perfil de los trabajadores atendidos en Hospital de Hematología de Recife

O estudo objetivou conhecer o perfil dos trabalhadores em faixa etária economicamente ativa admitidos de 1997 a 2007 em hospital de hematologia com diagnóstico de leucemia mieloide aguda (LMA); verificar as profissões com maior prevalência entre os trabalhadores atendidos que foram a óbito e identificar os riscos ocupacionais compatíveis com o aparecimento da LMA nas profissões prevalentes. Estudo exploratório de natureza quantitativa. A maior parte dos perfis caracterizou-se por ser procedente do agreste e da região metropolitana do estado, do sexo masculino, pertencente à raça branca e com grau de escolaridade fundamental incompleto. As ocupações de maior destaque foram aquelas relacionadas à agricultura e ao trabalho doméstico, sendo as substâncias químicas utilizadas no processo de trabalho de ambas, de acordo com a literatura, possíveis fatores envolvidos no desencadeamento da patologia.

The objective of this study was to learn the profile of workers in the economically active age group admitted from 1997 to 2007 to a hematology hospital, diagnosed with acute myeloid leukemia (AML); check which professions have the highest prevalence among the assisted workers who died; and identify the occupational risks compatible with the appearance of AML in the prevalent professions. This is a quantitative, exploratory study. Most profiles were characterized as originally from the agreste and the metropolitan region of the state of Pernambuco, male, white, and with incomplete primary education. The most common occupations were related to agriculture and domestic work, both of which involve the use of chemical substances that, according to literature, are possible factors involved in triggering the pathology.

Se objetivó conocer el perfil de trabajadores en faja etaria económicamente activa admitidos de 1997 a 2007 en hospital de hematología con diagnóstico de leucemia mieloide aguda (LMA); verificar las profesiones más prevalentes entre los pacientes atendidos que fallecieron e identificar los riesgos ocupacionales compatibles con la aparición de LMA en las profesiones predominantes. Estudio exploratorio, cuantitativo. Perfil encontrado: se caracterizó por la procedencia, en su mayoría de zonas agrestes y de regiones metropolitanas del estado, sexo masculino, raza blanca, fueron los más proclives a contraer la enfermedad. La enseñanza fundamental incompleta fue el grado educativo más recurrente. Las ocupaciones de prevalencia fueron aquellas relacionadas con el trabajo agrícola y el trabajo doméstico. Las substancias químicas utilizadas en el proceso de trabajo de ambas, de acuerdo a la literatura, son potenciales factores involucrados en el desencadenamiento de la patología.

Haematological & molecular profile of acute myelogenous leukaemia in India.

Background & objectives: Recurrent balanced translocations are generally recognized to be a major parameter for prognostication in acute myeloid leukaemia (AML). The chromosomal translocation t(15;17) results in PML/RARα fusion gene, t(8;21) results in AML1/ETO fusion gene and Inv 16 generates CBFβ/MYH11 fusion gene. Patients with these mutations have a good prognosis unlike abnormalities in chromosome 5 or 7 or FLT3 genes. Therefore, we screened the AmL patients for known specific genetic abnormalities that could lead to more definitive prognoses. Methods: A total of 113 AML patients were evaluated at diagnosis based on routine morphology and cytochemistry and classified according to the WHO criteria. The distribution of AML subtypes was M1(1), M2(32), M3(57), M4(14), M5(1), M6(1) and seven cases where morphological subtype could not be classified. RT-PCR was performed to identify PML/RARα, AML1/ETO, CBFβ/MYH11 and FLT3 internal tandem duplication (ITD). Results: Of the 57 patients with M3 subtype, 55 had the PML-RARα fusion transcript. The prevalence of bcr3 (short isoform) was higher (62%) than that of bcr1 (long isoform) (38%) and no correlation was found with age, sex or white blood cell count. FLT3 internal tandem duplication (ITD) mutations were more frequent in patients with APL than in other AML subtypes (17.5 vs. 8.9%), the frequency greater in patients with bcr3 isoform (70%) than in those with in bcr1 isoform (30%). Patients with FLT3/ITD mutations had a significantly higher median white cell count than those without these mutations (55 x 109/l vs. 6.3 x 109/l; P<0.001). More patients with FLT3/ITD mutations died early (53%) than those without these mutations (16%) (P<0.01). AML1-ETO fusion transcript was detected in 16 of 56 patients with no correlation with clinical or haematological parameters. Interpretation & conclusion: The results of the present study showed presence of bcr3 (short isoform) higher than bcr1 (long isoform). FLT3 internal tandem duplication (ITD) mutation was predominant in acute promyelocytic leukaemia patients with bcr3 isoform. Thus, patients with APL who have FLT3 mutation appear to have a poorer prognosis. Therefore, rapid identification of specific translocations at diagnosis is important for prognostic purposes and their detection should be incorporated into routine assessment.

Facteurs pronostiques des leucémies aiguës au CHU de Brazzaville

Les leucémies aiguës restent des affections dont le pronostic est redoutable malgré les progrès actuels. Plusieurs facteurs ont une influence variable sur l'évolution ou l'expression de son agressivité. Nous nous sommes fixés comme objectif de les déterminer en milieu hospitalier Brazzavillois.Une enquête rétrospective a été réalisée entre le 1er janvier 1995 et le 30 juin 2006. Elle a portésur 82 patients (33 hommes et 49 femmes).L'appui des laboratoires étrangers a été nécessaire pour pratiquer dans certains cas des examens cytogénétiques et immunophénotypiques. Nous avons trouvé 29 leucémies aiguës myéloïdes et 53 lymphoïdes.En plus des facteurs épidémiologiques; cliniques et biologiques; des anomalies chromosomiques ont été rapportées pour expliquer le mauvais pronostic enregistré

AML1-ETO positive AML: first report from India.

Translocation (8;21) is associated with few typical morphological features and favorable prognosis. All patients of AML and MDS with increased blasts (N = 35) according to FAB criteria, presenting (between Jan 2004 to June 2005) to the Department of Hematology, AIIMS were studied. RT-PCR was done for the AML1-ETO fusion transcript in all cases. Overall incidence of AML1-ETO was 28.57% and no correlation was found between AML1-ETO positivity and clinical or hematological parameters except for a direct correlation with absolute blast count (ABC) (a lower ABC in the AML1-ETO positive cases). Interestingly, 1/3 MDS cases were positive for the same fusion transcript and thus, it appears worthwhile to look for AML1-ETO in all cases of MDS with increased blasts. Objective morphological evaluation using a scoring system based on morphological features was not helpful in predicting positivity for AML1-ETO. The effect of this translocation on long-term survival could not be determined by the present study.

Leukemia as a second malignancy.

To study the occurrence of leukemia as a second malignancy following various primary solid and hematological malignancies. Total 11 cases of leukemia presenting as a second malignancy were studied over a period of 15 years from 1990 to 2005. The primary malignancies included carcinoma breast (4), multiple myeloma (3) and one each of Hodgkin's lymphoma, mediastinal germ cell tumor, papillary carcinoma thyroid and myxopapillary ependymoma. Ten patients had received chemotherapy with combination radiotherapy in six patients. The commonest type of leukemia was AML-M2. The cyogenetic test results were available in three cases. The secondary leukemia showed aggressive behaviour and all patients on follow-up died within a period of one month. The risk benefit ratio of chemotherapy and radiotherapy should be considered before starting the patients on treatment. A high degree of suspicion and follow up with hematological parameters is required for therapy related complications.

Acute childhood leukemias and exposure to magnetic fields generated by high voltage overhead power lines - a risk factor in Iran.

Many investigators have studied the effects of Extremely Low Frequency-Magnetic Fields generated by ordinary and domestic power lines, as a risk factor in acute leukaemias of children, but there are limited information available regarding very high voltage overhead power lines. Children in developing countries sometimes live very close to such structures and we have registered several patients with acute leukaemias appearing in clusters. In the present study we have analyzed 60 consecutively diagnosed patients with acute leukaemias, and 59 matched controls in a provincial capital city in North-Western Iran. After provision of consent, a detailed form was filled in, and a visit to the present (or previous) residential areas of both groups was arranged. The locations of the very high voltage power lines (123, 230, 400 kilo volts), were noted in each area, if present, and their distances from the houses under study were detected. The expected intensities of the Magnetic Fields (B) were calculated having the mean intensity of the electrical current and other line characteristics, by means of relevant equations. Fourteen patients in the case group (23.5%) were living near the high voltage power lines in distances < or = 500 meters. (Mean B = 0.6 microTeslas, microT). In the control group at the same distance, the figure was 2 children (3.3%) (Mean B = 0.35 microT). Statistically, the likelihood of leukaemia was increased considerably in this distance (Odds ratio (OR) = 8.67, 95% Confidence Interval (CI) = 1.74- 58.4, P value= 0.001). On the other hand 15 pts (25 %) in the leukaemia group were experiencing Magnetic fields above 0.45 microT in comparison to 5 in the control group ( 8.5% )(OR = 3.60, 95% CI = 1.11-12.39, P = 0.01). More children in developing countries like Iran live close to very high voltage lines, and they experience relatively more harmful effects from the Magnetic Fields, in comparison with children in developed countries. Residence near very high voltage overhead power lines, in distances < or = 500 meters, and Magnetic Fields >0.45 microT, should be considered a risk factor for the pathogenesis of acute leukaemias in children.

Specific chromosomal abnormalities in patients with acute nonlymphocytic leukemia from the Islamic Republic of Iran.

Cytogenetic analysis performed at diagnosis is considered to be the most valuable prognostic factor in acute non-lymphocytic leukemia (ANLL), a very heterogeneous disease. Little data exist in Iran regarding the cytogenetic characteristics of ANLL . Therefore, cytogenetic investigations were performed for 58 patients with various subtypes of ANLL with unstimulated short term culture and high resolution cell synchronization techniques. Among the 58 evaluated patients, 45 (77.5%) showed clonal karyotypic abnormalities and the percentages of the abnormal cells were recorded within the range of 30%-100%. Some 14 were classified as M1, 20 as M2, 19 as M3 , 3 as M4, 1 as M5 and 1 as M6. The most common chromosome rearrangements were t(15;17), t( 8;21) and t(9;22). Trisomy of chromosome 8 (+8) was the most frequent numerical alteration in 3 patients with M1, M2 and M6. The incidence of other chromosomal defects, including -10, DMCs , -19 , 5q- , dicentric(dic), chromatid breaks, and marker chromosomes was relatively high. Similarities and dissimilarities of our study with others may be due to the role of genetic sensitivities as well as uneven geographic distribution in the pathogenesis of ANLL. Further prospective studies are warranted to precisely elucidate ethnic differences in the pathogenesis of this disease in different populations.

Trends in incidence of childhood leukemia, Khon Kaen, Thailand, 1985-2002.

BACKGROUND: The Khon Kaen Cancer Registry (KKCR), providing both hospital and population-based registration, was established in 1984 in the Faculty of Medicine, Khon Kaen University. Leukemia is the most common cancer among Thai children in Thailand, including both curable and preventable types, but no assessment of trends has hitherto been performed. OBJECTIVE: To perform a statistical assessment of the incidence trend of childhood leukemia in Khon Kaen, Thailand, between 1985 and 2002. METHODS: Population-based cases of childhood leukemia registered between 1985 and 2002 were retrieved from the KKCR and cases with an ICD-O diagnosis (coding C42) in children under 15 were selected. Incidence trends were calculated using the Generalized Linear Model method (GLM), which generates incidence-rate-based logarithms. RESULTS: Of the 277 cases of leukemia, boys were affected two times more frequently than girls and half of the cases were 0-4 years of age. Most diagnoses were histologically- or cytologically-proven and the most common type (affecting two-thirds, 65.7%) was acute lymphoblastic leukemia (ALL). The overall, age-standardized rate (ASR) for leukemia was 31.9 per million (95%CI: 28.1 to 35.7); 40.3 per million (95%CI: 34.2 to 46.4) in boys and 27.0 (95%CI: 21.8 to 32.2) in girls. Incidence has been increasing by 2.4% per year in boys (95% CI: -0.5 to 5.3) and 4.1% per year in girls (95% CI: 1.1 to 7.2). CONCLUSIONS: This incidence-rate-based logarithm indicates that childhood leukemia has been increasing, suggesting further epidemiological research on causes and possible prevention is needed.