Follow-up and outcome of the twelve-year experience in adult patients with acute promyelocytic leukemia

ABSTRACT Acute promyelocytic leukemia is a subtype of acute myeloid leukemia, characterized by the presence of neoplastic promyelocytes, due to the reciprocal balanced translocation between chromosomes 15 and 17. Currently, with the use of agents that act directly on this molecular change, such as all-trans retinoic acid and arsenic trioxide, APL has shifted from a highly mortal to a curable disease. However, some cases are still at high risk of death, especially early death, and acquiring a better understanding of the clinical and biological factors involving APL is needed to correctly identify and treat such cases. The early suspected diagnosis and prompt initiation of the target therapy are important for better response rates. The follow-up and outcomes, using real-life data from 44 consecutive APL patients, were studied between 2001 and 2013. The overall survival rate was 82.7% and early death was 16%. Almost all patient deaths were due to severe bleeding, which was confirmed by multivariate analysis, as the most important prognostic factor leading to death. A better understanding the pathogenesis of the hemorrhagic complications in APL is needed, as well as the risk factors associated with early death in APL patients, as this has become synonymous with overall mortality.

Follow-up and outcome of the twelve-year experience in adult patients with acute promyelocytic leukemia.

Acute promyelocytic leukemia is a subtype of acute myeloid leukemia, characterized by the presence of neoplastic promyelocytes, due to the reciprocal balanced translocation between chromosomes 15 and 17. Currently, with the use of agents that act directly on this molecular change, such as all-trans retinoic acid and arsenic trioxide, APL has shifted from a highly mortal to a curable disease. However, some cases are still at high risk of death, especially early death, and acquiring a better understanding of the clinical and biological factors involving APL is needed to correctly identify and treat such cases. The early suspected diagnosis and prompt initiation of the target therapy are important for better response rates. The follow-up and outcomes, using real-life data from 44 consecutive APL patients, were studied between 2001 and 2013. The overall survival rate was 82.7% and early death was 16%. Almost all patient deaths were due to severe bleeding, which was confirmed by multivariate analysis, as the most important prognostic factor leading to death. A better understanding the pathogenesis of the hemorrhagic complications in APL is needed, as well as the risk factors associated with early death in APL patients, as this has become synonymous with overall mortality.

Evaluation of CD307a expression patterns during normal B-cell maturation and in B-cell malignancies by flow cytometry.

BACKGROUND: Flow cytometric immunophenotyping is deemed a fundamental tool for the diagnosis of B-cell neoplasms. Currently, the investigation of novel immunophenotypic markers has gained importance, as they can assist in the precise subclassification of B-cell malignancies by flow cytometry. Therefore, the purpose of the present study was to evaluate the expression of CD307a during normal B-cell maturation and in B-cell malignancies as well as to investigate its potential role in the differential diagnosis of these entities. METHODS: CD307a expression was assessed by flow cytometry in normal precursor and mature B cells and in 115 samples collected from patients diagnosed with precursor and mature B-cell neoplasms. CD307a expression was compared between neoplastic and normal B cells. RESULTS: B-acute lymphoblastic leukemia cases exhibited minimal expression of CD307a, displaying a similar expression pattern to that of normal B-cell precursors. Mantle cell lymphoma (MCL) cases showed the lowest levels of CD307a among mature B-cell neoplasms. CD307a expression was statistically lower in MCL cases than in chronic B lymphocytic leukemia (CLL) and marginal zone lymphoma (MZL) cases. No statistical differences were observed between CD307a expression in neoplastic and normal plasma cells. CONCLUSION: These results indicate that the assessment of CD307a expression by flow cytometry could be helpful to distinguish CLL from MCL, and the latter from MZL. Although these results are not entirely conclusive, they provide a basis for further studies in a larger cohort of patients. © 2018 International Clinical Cytometry Society.

Determination of normal expression patterns of CD86, CD210a, CD261, CD262, CD264, CD358, and CD361 in peripheral blood and bone marrow cells by flow cytometry.

In 2010, new monoclonal antibodies were submitted to the 9th International Workshop on Human Leukocyte Differentiation Antigens, and there are few studies demonstrating normal expression patterns of these markers. Thus, the objective of this study was to determine the normal patterns of cell expression of CD86, CD210a, CD261, CD262, CD264, CD358, and CD361 in peripheral blood (PB) and bone marrow (BM) samples by flow cytometry. In the present study, CD86 was expressed only in monocytes and B lymphocytes in PB and in monocytes and plasma cells in BM. Regarding CD210a expression, in PB samples, monocytes and NK cells showed weak expression, while neutrophils, B and T lymphocytes, and basophils showed weak and partial expression. In BM samples, expression of CD210a was observed in eosinophils, monocytes, and B and T/NK lymphocytes. Weak expression of CD210a was also observed in neutrophilic cells and plasma cells. All B cell maturation stages had weak expression of CD210a except for immature B cells, which did not express this marker. In the present study, no cell type in PB samples showed positivity for CD261 and, in BM samples, there was very weak expression in neutrophilic series, monocytes, and B lymphocytes. Conversely, plasma cells showed positivity for CD261 with a homogeneous expression. For CD262, there was weak expression in monocytes, neutrophils, and B lymphocytes in PB samples and weak expression in monocytes, B lymphocytes, and plasma cells in BM samples. The evaluation of CD264 showed very weak expression in B cells in PB samples and no expression in BM cells. Very weak expression of CD358 was observed in neutrophils, monocytes, and B lymphocytes in PB and BM samples. In addition, in BM samples, plasma cells and T lymphocytes showed weak expression of CD358. In relation to the maturation stages of B cells, there was weak expression in pro-B cel, pre-B cell, and mature B cell. In the present study, it was possible to observe expression of CD361 in all cell types analyzed in PB and BM samples. The analyzed markers presented varied profiles of expression and, in some cases, these profiles were different from those observed in other studies. Further studies are needed to evaluate these molecules, mainly in relation to a possible application in the diagnosis of hematological malignancies or as new therapeutic targets for the treatment of hematological neoplasms or autoimmune diseases.

The importance of CD39, CD43, CD81, and CD95 expression for differentiating B cell lymphoma by flow cytometry.

BACKGROUND: B cell lymphomas' (BCL) current diagnosis is usually based on a combination of morphology, immunophenotype, recurrent cytogenetic aberration and clinical features. However, even with these diagnostic tools, a definitive diagnosis can be difficult to achieve. Therefore, the aim of this study was to assess the profile of CD39, CD43, CD81, and CD95 expressions in diffuse large B cell lymphoma (DLBCL), follicular lymphoma (FL), and Burkitt lymphoma (BL) cases. METHODS: To address this issue, we investigated the expression of CD39, CD43, CD81, and CD95 by eight-color flow cytometry in retrospective cases from 2014 to 2016. RESULTS: The study included 27 adult patients diagnosed with DLBCL, FL, and BL during the study period. Four patients were diagnosed with germinal center B cell-like DLBCL (GCB DLBCL), seven with non-GCB DLBCL, nine with FL, and seven with BL. CD39 seems to be especially relevant to differentiate non-GCB DLBCL from BL and from FL. BL showed stronger expression of CD43 when compared to FL and GCB DLBCL. Moreover, CD43 may help to distinguish non-GCB DLBCL from GCB DLBCL. CD81 expression was much stronger in BL when compared to the other three groups of patients. Lastly, CD95 may also help to distinguish BL from the other subtypes, as BL cells expressed this antigen at low levels. CONCLUSIONS: In combination, CD39, CD43, CD81, and CD95 expressions appear to be helpful to distinguish CD10+ BCL, particularly BL. Phenotypic distinction between FL and GCB DLBCL remains challenging and requires further studies. © 2017 International Clinical Cytometry Society.

Evaluation of seven rapid tests for syphilis available in Brazil using defibrinated plasma panels.

OBJECTIVES: In 2012, the WHO estimated that 6 million new cases of syphilis per year would occur worldwide, including 937 000 in Brazil. Early diagnosis and treatment of syphilis are essential to reduce morbidity and prevent transmission. The availability of rapid tests (RTs) for this diagnosis means that testing can be performed more quickly, as a point-of-care test, even in non-laboratory environments and requires only simple technical training to antibodies detection. The objective of this study was to evaluate the performance and operational aspects of seven commercially available RTs for syphilis in Brazil. METHODS: Seven rapid treponemal tests were evaluated for sensitivity, specificity, accuracy and Kappa value, according to a panel composed of 493 members. The operational performance of the assay was also determined for these tests. RESULTS: The seven RTs showed sensitivity ranging from 94.5% to 100% when compared with the reference tests and specificity of between 91.5% and 100%. All the RTs evaluated presented good operational performance, and only one failed to present the minimum specificity as defined by Brazil's Ministry of Health. CONCLUSION: All the tests presented good operational performance, and the professionals who performed them considered them to be easy to use and interpret. This evaluation is important for making informed choices of tests to be used in the Brazilian Unified Health System.

Determination of lymphocyte subset reference ranges in peripheral blood of healthy adults by a dual-platform flow cytometry method.

Flow cytometry has emerged as a useful screening approach to evaluate whether specific cell populations are present or absent. Previous studies have shown different reference ranges in several countries. The aim of this study was to determine reference ranges of lymphocyte subsets in peripheral blood by flow cytometric method in Brazilian adults. In this study, relative and absolute reference ranges of lymphocyte subsets were: CD3+: 51.3-83.5%, 718-2494cells/µl; CD4+: 24.4-54.2%, 456-1492cells/µl; CD8+: 12.8-40.2%, 272-1144cells/µl; CD4+CD8+: double-positive 0.01-3.6%, 2-88cells/µl; TCR γδ: 1.0-15.9%, 19-345cells/µl; CD3+CD4-CD8-: 1.2-13.3%, 28-292cells/µl; TCR αß+: 44.3-77.0%, 855-2384cells/µl; CD4/CD8 ratio: 0.68-3.61; CD19+: 6.3-20.8%, 112-622cells/µl; mature NK cells: 3.1-27.4%, 70-745cells/µl; immature NK cells: 0.08-1.1%, 1-23cells/µl; total NK cells: 3.7-28.5%, 82-760cells/µl; and NKT cells: 0.9-21.4%, 18-488cells/µl. Comparison with other studies showed differences among some of them. This suggests that there are differences among lymphocyte subsets in the worldwide population and also it is important to determine reference ranges in different populations in order to better assess and monitor patients.

Comparison between two portable hemoglobinometers and a reference method to verify the reliability of screening in blood donors.

Portable hemoglobinometers are used to determine hemoglobin level, but there are conflicting reports regarding their accuracy. The aim of this study was to compare results from two portable hemoglobinometers (HemoCue® and Hemo-Control) with an automated hematology analyzer (Sysmex XE-2100D) to determine if the screening of blood donors is reliable. A total of 426 blood donors' samples were studied and on average the Hb content measured in capillary blood samples was higher than that found in venous blood samples. Hemoglobinometers can be employed as a method to screen blood donors, but critical values should be confirmed in an automated hematology analyzer.