RESUMO
CONTEXT: The CDR-3 region of heavy-chain immunoglobulin has been used as a clonal marker in the study of minimal residual disease in children with acute lymphoblastic leukemia. Southern blot and polymerase chain reaction studies have demonstrated the occurrence of bi/oligoclonality in a variable number of cases of B-lineage acute lymphoblastic leukemia, a fact that may strongly interfere with the detection of minimal residual disease. Oligoclonality has also been associated with a poorer prognosis and a higher chance of relapse. OBJECTIVES: To correlate bi/oligoclonality, detected by polymerase chain reaction in Brazilian children with B-lineage acute lymphoblastic leukemia with a chance of relapse, with immunophenotype, risk group, and disease-free survival. DESIGN: Prospective study of patients outcome. SETTING: Pediatric Oncology Unit of the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo. PARTICIPANTS: 47 children with acute lymphoblastic leukemia DIAGNOSTIC TEST: Polymerase chain reaction using consensus primers for the CDR-3 region of heavy chain immunoglobulin (FR3A, LJH and VLJH) for the detection of clonality. RESULTS: Bi/oligoclonality was detected in 15 patients (31.9%). There was no significant difference between the groups with monoclonality and biclonality in terms of the occurrence of a relapse (28.1% versus 26.1%), presence of CALLA+ (81.2% versus 80%) or risk group (62.5% versus 60%). Disease-free survival was similar in both groups, with no significant difference (p: 0.7695). CONCLUSIONS: We conclude that bi/oligoclonality was not associated with the factors investigated in the present study and that its detection in 31.9% of the patients may be important for the study and monitoring of minimal residual disease.
Assuntos
Linfoma de Burkitt/genética , Adolescente , Linfoma de Burkitt/imunologia , Linhagem Celular , Criança , Pré-Escolar , Regiões Determinantes de Complementaridade/genética , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Imunofenotipagem , Lactente , Masculino , Neprilisina/análise , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Prognóstico , Estudos Prospectivos , Recidiva , Fatores de RiscoRESUMO
CONTEXT: Mutations of the p53 tumor suppressor gene are the most frequent alterations observed in human neoplasias affecting adults. In pediatric oncology, however, they have seldom been identified. Wilms' tumor is a renal neoplasia commonly occurring in children and is associated with mutations of the WT1 gene. The correlation between Wilms' tumor and alterations of the p53 gene has not been well established, with a low frequency of mutations having been reported in this type of tumor. Mutation may be associated with advanced stage disease and unfavorable histology. OBJECTIVE: To screen for mutations of the p53 gene by the PCR-SSCP method and DNA sequencing in cases of Wilms' tumor sug-gestive of mutation. DESIGN: Case Report. CASE REPORT: Evaluations of exons 5-9 of the p53 gene in DNA samples extracted by PCR-SSCP from 10 Wilms' tumors in children at different stages, and DNA sequencing. Changes in SSCP analy-sis were observed in exon 8 in two samples. The probable muta-tions were not confirmed by DNA sequencing. The absence of point mutations in p53 gene observed in the 10 samples of Wilms' tumor studied agrees with literature data, with DNA sequencing being of fundamental importance for the confirmation of possible mutations.
Assuntos
Genes do Tumor de Wilms/genética , Genes p53/genética , Neoplasias Renais/genética , Mutação/genética , Tumor de Wilms/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase/métodos , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNARESUMO
OBJECTIVE: To describe the occurrence of transient pancytopenia induced by parvovirus B19 infection in a patient with hereditary hemolytic anemia and to discuss the importance of the diagnosis of this pathology.METHODS: Case report of a child whose diagnosis was made by polymerase chain reaction (PCR) and serology, and review of the literature.CLINICAL REPORT: A twelve year-old male patient with hereditary spherocytosis, presenting non-specific symptoms of an infectious syndrome followed by severe and transient pancytopenia, whose diagnosis was a parvovirus B19 infection.CONCLUSION: The diagnosis of parvovirus infection has a particular importance in hematology, especially on some morbid conditions, among them the hereditary hemolytic anemias. PCR is useful because of its rapidness and sensitivity on the specific diagnosis of this disease.
RESUMO
PURPOSE: B cell precursors acute lymphoblastic leukemia (ALL) present rearrangements in the heavy chain immunoglobulin and T cell receptor genes, especially in the complementarity determining region 3 (CDR-3) and T cell receptor delta (TCR delta) (V delta 2 D delta 3) regions. These rearrangements may be amplified by the polymerase chain reaction (PCR) and used as clonal markers of B lineage ALL. Our purpose was to study clonality at the DNA level by PCR in B lineage ALL. PATIENTS AND METHODS: Fifty-three pediatric patients (36 with B lineage ALL, 7 with ALL-T, and 10 with nonlymphocytic disease) were investigated using consensus primers for the CDR-3 regions of IgH and TCR delta. RESULTS: Clonality was detected in 86.1% of the patients with B lineage ALL when the primers for the CDR-3 regions were used, in 41.6% when the primers for TCR delta were used, and in 91.6% when the two primers were used together. Biclonality was found in 22.5% and 6.6% of patients that have shown clonality for CDR-3 and TCR delta, respectively. Clonality was not detected in any other samples using these primers. CONCLUSIONS: PCR using CDR-3 and TCR delta primers can be used as an aid for B lineage ALL diagnosis and clonal evolution of theses disease.
Assuntos
Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Criança , Pré-Escolar , Células Clonais , Sequência Consenso , Primers do DNA , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Feminino , Amplificação de Genes , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Rearranjo Gênico da Cadeia delta dos Receptores de Antígenos dos Linfócitos T , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Lactente , Masculino , Reação em Cadeia da Polimerase , Receptores de Antígenos de Linfócitos T gama-delta/genéticaRESUMO
The authors studied cytogenetically a case of CD30+ anaplastic large cell non-Hodgkin lymphoma previously diagnosed as malignant histiocytosis and detected a translocation involving chromosomes 1 and 5, t(1;5)(q32:q35). After comparing their findings with those from reports in the literature, they comment about the importance of breakpoint q35 on chromosome 5 and point out the importance of associating morphologic, immunoperoxidase, and cytogenetic findings to confirm the diagnosis of this tumor.