Nydia Strachman Bacal

Autologous cord blood transplantation.

Placental blood transplantation has been used to restore bone marrow function after intensification chemotherapy for hematological malignancies and other tumors. 1–3 When it was demonstrated that cord blood could be stored for later use, some commercial providers suggested storing cord blood as a form of insurance and tried to sell the idea that should the child develop a cancer some day the placental blood stored would be useful and perhaps lifesaving. There are no risk/benefit studies that can or cannot justify this procedure. Some recent findings showing that leukemic blood cells are present in fetal and neonatal blood of patients diagnosed with leukemia at 10 years are a strong argument against ‘insurance storage’, at least for future use in future leukemias. 4

Development of plasma cell myeloma in a B-cell chronic lymphocytic leukemia patient with chromosome 12 trisomy

BackgroundCancer development results from the progressive accumulation of genomic abnormalities that culminate in the neoplastic phenotype. Cytogenetic alterations, mutations and rearrangements may be considered as molecular legacy which trace the clonal history of the disease. Concomitant tumors are reported and they may derive from a common or divergent founder clone. B-cell chronic lymphocytic leukemia (B-CLL) and plasma cell myeloma (PCM) are both mature B-cell neoplasms, and their concomitancy, albeit rare, is documented.Case presentationHere, we described a patient with prior B-CLL with secondary development of PCM. Cytogenetic and multi parametric flow cytometry analyses were performed. The B-CLL population presented chromosome 12 trisomy, unlikely the arisen PCM population.ConclusionThe close follow up of B-CLL patients is important for early intervention in case of development of other malignancy, such as myeloma. Our observation suggests these two diseases may have arisen from different clones. We understand that the investigation of clonal origin may provide important information regarding therapeutic decisions, and should be considered in concomitant neoplasm.

Evaluation of Two Methods for Determination of CD64 as a Diagnostic Marker of Infection in Critically Ill Adults

Objectives. Diagnostic markers of infection have had little innovation over the last few decades. CD64, a marker expressed on the surface of neutrophils, may have utility for this purpose. Methods. This study was conducted in an adult intensive care unit (ICU) in São Paulo, Brazil, with 89 patients. We evaluated CD64 in patients with documented or clinically diagnosed infection (infection group) and controls (patients without any evidence of infection) by two different methodologies: method #1, an in house assay, and method #2, the commercial kit Leuko64 (Trillium Diagnostics). Results. CD64 displayed good discriminating power with a 91.2% sensitivity (95% CI 90.7–91.6%) for detecting infection. The commercial kit (Leuko64) demonstrated higher specificity (87.3%) compared with method #1 as well as better accuracy (88.8%). Conclusions. CD64 seems to be a promising marker of infection in the intensive care setting, with Leuko64 showing a slight advantage.

Metastatic melanoma mimicking acute leukaemia.

A 71-year-old male who was immunosuppressed following liver transplantation underwent resection of a 3 1 mm-deep melanoma on his back. At the time of surgery, a positron emission tomography/computed tomography (PET-CT) scan and biopsy of the left sentinel axillary lymph nodes showed no evidence of metastasis. Three months later he presented with back pain. Another PET-CT was performed, which showed uptake in the left axilla and diffuse activity in the bone marrow. Blood counts were normal and lactic dehydrogenase was 20 times normal. A bone marrow aspirate (upper left) and staining with alpha naphthyl acetate esterase (upper right) were suggestive of acute monocytic leukaemia. Flow cytometry identified a population of cells that were CD45 , CD117+, CD61+, CD71+, CD56+ and were negative for myeloid markers. Bone marrow biopsy sections stained with haematoxylin and eosin (bottom left) and HMB45, recognizing a melanocyte antigen (bottom right), confirmed massive infiltration by melanoma. The axillary lymph nodes were also infiltrated. The tumour was tested for BRAF mutations and was found to harbour c.1801A > G resulting in K601E substitution and 1750C > T resulting in L584F substitution. Little is known about the clinical implication of these mutations. Despite a significant initial response to treatment with vemurafenib, the patient developed numerous brain metastases within 8 weeks and died 2 weeks later. We attribute the atypical pattern of metastasis to the transplantrelated immunosuppression.

Molecular and cytogenetic abnormalities in acute myeloid leukemia: review and case studies.

OBJECTIVE To study the frequency of mutations that may lead to a good or bad prognosis, as well as their relation with the karyotype and immunophenotype in patients with acute myeloid leukemia. METHODS Thirty samples of patients with acute myeloid leukemia were studied, in which FLT3-ITD, FLT3-TKD and NPM1 mutations were investigated. All samples were submitted to immunophenotyping and 25 to karyotyping. RESULTS An occurrence of 33.3% NPM1 mutation and an equal number of FLT3-ITD mutation were observed. When only the cases with normal karyotype were studied, this figures increased to 50 and 40%, respectively. Eight percent of cases with normal karyotype and genotype NPM1+/FLT3- were included in the group of acute myeloid leukemia with good prognosis. The typical phenotype of acute myeloid leukemia with normal karyotype and mutated NPM1 (HLA-DR and CD34 negative) was not observed in this small series. CONCLUSION Good prognosis cases were identified in this series, emphasizing the need to include new genetic markers in the diagnostic routine for the correct classification of acute myeloid leukemia, to more properly estimate prognosis and determine treatment.

A Novel Assay for the Identification of NOTCH1 PEST Domain Mutations in Chronic Lymphocytic Leukemia

Aims. To develop a fast and robust DNA-based assay to detect insertions and deletions mutations in exon 34 that encodes the PEST domain of NOTCH1 in order to evaluate patients with chronic lymphocytic leukemia (CLL). Methods. We designed a multiplexed allele-specific polymerase chain reaction (PCR) combined with a fragment analysis assay to detect specifically the mutation c.7544_7545delCT and possibly other insertions and deletions in exon 34 of NOTCH1. Results. We evaluated our assay in peripheral blood samples from two cohorts of patients with CLL. The frequency of NOTCH1 mutations was 8.4% in the first cohort of 71 unselected CLL patients. We then evaluated a second cohort of 26 CLL patients with known cytogenetic abnormalities that were enriched for patients with trisomy 12. NOTCH1 mutations were detected in 43.7% of the patients with trisomy 12. Conclusions. We have developed a fast and robust assay combining allele-specific PCR and fragment analysis able to detect NOTCH1 PEST domain insertions and deletions.

Recommendations for quality assurance in multiparametric flow cytometry: first consensus of the Brazilian Group of Flow Cytometry (GBCFLUX)

The Brazilian Group of Flow Cytometry (Grupo Brasileiro de Citometria de Fluxo [GBCFLUX]), founded on April 24, 2010, is composed of experts in flow cytometry (FC) area who have the common objective of contributing to technical and scientific advances in Brazilian clinical and research laboratories. Among GBCFLUX working groups, the Quality Control (QC) subcommittee is responsible for discussing data in the literature and contributes to the quality assurance of the pre-analytical, analytical and post-analytical process in FC. The QC subcommittees actions began through meetings and lectures, in which data from the literature were reviewed and discussed with all participating members of the GBCFLUX. In a second step, it was decided to draw up a text of technical and scientific consensus recommendations, informative and educative, for dissemination to all FC working groups in Brazil. To this effect, a questionnaire with objective responses was designed and sent to 35 recognized Brazilian institutions, in order to evaluate the QC profile of these institutions. Thus, the QC technical-scientific recommendations, which will be described in this updating article, are intended to ensure the process quality, technical standardization, and reproducibility of results in FC.

Involvement of memory T-cells in the pathophysiology of chronic lymphocytic leukemia

The role of T-cells in the pathogenesis of chronic lymphocytic leukemia has recently gained much attention due to the importance of the constant interaction between neoplastic B-cells with microenvironment substratum and T-cells. It is believed that these interactions modulate the clinical course of the disease, mainly through the regulation of the expansion, differentiation, and survival of chronic lymphocytic leukemia B-cells. Importantly, this crosstalk may also change the number, function, and memory phenotype of normal T-cells, thereby altering the amplitude and/or efficiency of adaptive immunity in chronic lymphocytic leukemia patients. The present study presents an overview on important aspects of this immunological crosstalk, particularly on the abnormalities of chronic lymphocytic leukemia B-cells and the alterations in normal T-cells, with focus on the CD4 memory T-cell compartment that could offer survival signals to chronic lymphocytic leukemia B-cell clone(s) and contribute to the establishment and progression of the disease. The authors believe that understanding the biological consequences of the interaction between normal T- and neoplastic B-cells in chronic lymphocytic leukemia may allow for improvements in the prognostic information and therapeutic approaches for this disease.

Alterações citogenéticas e moleculares em leucemia mieloide aguda: revisão e descrição de casos

aBStraCt objective: To study the frequency of mutations that may lead to a good or bad prognosis, as well as their relation with the karyotype and immunophenotype in patients with acute myeloid leukemia. Methods: Thirty samples of patients with acute myeloid leukemia were studied, in which FLT3-ITD, FLT3-TKD and NPM1 mutations were investigated. All samples were submitted to immunophenotyping and 25 to karyotyping. results: An occurrence of 33.3% NPM1 mutation and an equal number of FLT3-ITD mutation were observed . When only the cases with normal karyotype were studied, this figures increased to 50 and 40%, respectively. Eight percent of cases with normal karyotype and genotype NPM1+/FLT3- were included in the group of acute myeloid leukemia with good prognosis. The typical phenotype of acute myeloid leukemia with normal karyotype and mutated NPM1 (HLA-DR and CD34 negative) was not observed in this small series. Conclusion: Good prognosis cases were identified in this series, emphasizing the need to include new genetic markers in the diagnostic routine for the correct classification of acute myeloid leukemia, to more properly estimate prognosis and determine treatment.

Diagnosis of chronic lymphoproliferative disorders by flow cytometry using four-color combinations for immunophenotyping: A proposal of the brazilian group of flow cytometry (GBCFLUX)

Multiparametric flow cytometry (MFC) is a powerful tool for the diagnosis of hematological malignancies and has been useful for the classification of chronic lymphoproliferative disorders (CLPD) according to the WHO criteria. Following the purposes of the Brazilian Group of Flow Cytometry (GBCFLUX), the aim of this report was to standardize the minimum requirements to achieve an accurate diagnosis in CLPDs, considering the different economic possibilities of the laboratories in our country. Most laboratories in Brazil work with 4‐fluorescence flow cytometers, which is why the GBCFLUX CLPD Committee has proposed 4‐color monoclonal antibody (MoAb) panels.