Diagnóstico de imunofenótipos de síndromes linfoproliferativas crônicas por citometria de fluxo na Fundação HEMOPA / Diagnosis of immunophenotyping of chronic lymphoproliferative syndromes by flow cytometry at HEMOPA blood center

INTRODUÇÃO: As síndromes linfoproliferativas formam um grupo heterogêneo de neoplasias malignas com diferentes comportamentos clínicos, fatores patológicos e características epidemiológicas e podem ter seu diagnóstico geral com base na morfologia das células linfoides observadas no sangue periférico. OBJETIVO: Testar a factibilidade diagnóstica do método de imunofenotipagem por citometria de fluxo para síndromes linfoproliferativas a partir da definição de um painel mínimo de anticorpos. MATERIAL E MÉTODOS: Participaram 47 pacientes para diagnóstico diferencial dos subtipos de síndromes linfoproliferativas por citometria de fluxo, no período de julho de 2008 a julho de 2010, atendidos na Fundação HEMOPA. RESULTADOS: A mediana de idade dos pacientes foi de 68 anos, não houve diferença estatística entre os sexos e o subtipo de síndromes linfoproliferativas mais frequente foi a leucemia linfoide crônica/linfoma linfocítico de pequenas células B. CONCLUSÃO: O método de imunofenotipagem por citometria de fluxo, ao lado da morfologia, de amostras de sangue periférico mostrou-se uma metodologia auxiliar, segura, rápida, factível e não invasiva para o diagnóstico de síndromes linfoproliferativas crônicas a partir do painel de anticorpos sugerido.

INTRODUCTION: Lymphoproliferative syndromes comprise a heterogeneous group of malignant neoplasias with different clinical behaviors, pathological factors and epidemiological characteristics, whose diagnosis may be based on lymphoid cell morphology observed in peripheral blood. OBJECTIVE: To test the diagnostic feasibility of immunophenotyping by flow cytometry for lymphoproliferative syndromes through the definition of minimal antibody panel. MATERIAL AND METHODS: During the period of July 2008 to July 2010, 47 patients from HEMOPA blood center participated in this study for differential diagnosis of lymphoproliferative syndromes subtypes by flow cytometry. RESULTS: The mean age was 68 years old. There was no statistical difference between genders, and the most frequent subtype of lymphoproliferative syndromes was chronic lymphoid leukemia/small B-cell lymphocytic lymphoma. CONCLUSION: Based on the antibody panel recommended in this investigation, the immunophenotyping method by flow cytometry associated with morphological characterization of peripheral blood samples is a reliable, rapid, feasible, and non-invasive procedure for the diagnosis of chronic lymphoproliferative syndromes.

Influence of late treatment on how chronic myeloid leukemia responds to imatinib

INTRODUCTION: In Brazil, patients with chronic myeloid leukemia (CML) in the chronic phase were not given first-line imatinib treatment until 2008. Therefore, there was a long period of time between diagnosis and the initiation of imatinib therapy for many patients. This study aims to compare the major molecular remission (MMR) rates of early versus late imatinib therapy in chronic phase CML patients. METHODS: Between May 2002 and November 2007, 44 patients with chronic phase CML were treated with second-line imatinib therapy at the Hematology Unit of the Ophir Loyola Hospital (Belém, Pará, Brazil). BCR-ABL transcript levels were measured at approximately six-month intervals using quantitative polymerase chain reaction. RESULTS: The early treatment group presented a 60 percent probability of achieving MMR, while the probability for those patients who received late treatment was 40 percent. The probability of either not achieving MMR within one year of the initiation of imatinib therapy or losing MMR was higher in patients who received late treatment (79 percent), compared with patients who received early treatment (21 percent, odds ratio=5.75, P=0.012). The probability of maintaining MMR at 30 months of treatment was 80 percent in the early treatment group and 44 percent in the late treatment group (P=0.0005). CONCLUSIONS: For CML patients in the chronic phase who were treated with second-line imatinib therapy, the probability of achieving and maintaining MMR was higher in patients who received early treatment compared with those patients for whom the time interval between diagnosis and initiation of imatinib therapy was longer than one year.