László Rejtő

WT1 Expression in Adult Acute Myeloid Leukemia: Assessing its Presence, Magnitude and Temporal Changes as Prognostic Factors

Expression of the gene Wilms tumor 1 (WT1) has been suggested as a marker of minimal residual disease in acute myeloid leukemia (AML), but literature data are not without controversy. Our aim was to assess the presence, magnitude and temporal changes of WT1 expression as prognostic factors. 60 AML patients were followed until death or the end of the 6-year observation period. Blood samples were taken at diagnosis, post-induction, during remission and in case of a relapse. Using quantitative real-time PCR, we determined WT1 expression from each sample, normalized it against the endogenous control gene glyceraldehyde 3-phosphate dehydrogenase (GAPDH), and classified samples as negative, moderately positive or highly positive. We divided the patients into groups based on detected WT1 expression values, illustrated overall and disease-free survival on Kaplan-Meier curves, and compared differences between each group by the logrank test. Disappearance of WT1-positivity during chemotherapy had a favorable effect on survival. Interestingly, no difference was seen between the survivals of WT1-positive subgroups that expressed moderate or high levels of WT1 mRNA. A 1-log decrease in WT1 expression without becoming negative did not affect prognosis, either. Our results suggest that defining a cut-off value for WT1-positivity, rather than just using logarithmic figures of changes in gene expression, might have prognostic use in post-induction AML patients. We encourage further, larger-scale studies.

WT1 Overexpression Affecting Clinical Outcome in Non-Hodgkin Lymphomas and Adult Acute Lymphoblastic Leukemia

The Wilms tumor 1 (WT1) gene has a complex role as a transcriptional regulator, acting as tumor suppressor or oncogene in different malignancies. The prognostic role of its overexpression has been well-studied in leukemias, especially acute myeloid leukemia (AML), but not in lymphomas. For the first time to our knowledge, we present a study demonstrating the correlation of WT1 expression and survival in various non-Hodgkin lymphomas. We also studied the prognostic implications of WT1 overexpression in adult acute lymphoblastic leukemia (ALL). In our sample of 53 patients—25 with diffuse large B-cell lymphoma (DLBCL), 8 with mantle cell lymphoma (MCL), 9 with peripheral T-cell lymphoma (PTCL), 2 with Burkitt’s lymphoma, 2 with mucosa-associated lymphoid tissue (MALT) lymphoma, and 7 with B-cell ALL—, we measured WT1 mRNA from blood samples by quantitative RT-PCR, and divided the patients into subgroups based on the level of expression. Kaplan–Meier survival curves were drawn and compared using the logrank test. In the sample of DLBCL patients, the difference in overall and disease-free survival between WT1-positive and negative subgroups was significant (p = 0.0475 and p = 0.0004, respectively), and in a few observed cases, a sudden increase in WT1 expression signified a relapse soon followed by death. Disease-free survival curves in MCL and ALL were similarly suggestive of a potential role played by WT1. In PTCL, though WT1-positivity was detected in 4 out of 9 cases, it did not seem to affect survival. The few cases of MALT and Burkitt’s lymphoma all proved to be WT1-negative.

Laboratory evaluation of a flow cytometric BCR-ABL immunobead assay

Abstract Background: A new flow cytometric (FC) BCR-ABL immunobead assay has been developed recently. Here we present the laboratory evaluation of the commercially available kit. Methods: Mononuclear cells were isolated, lysed and processed according to the instructions of the manufacturer. Anti-BCR antibodies adsorbed to capture beads bind the BCR-ABL fusion proteins of the lysed cells, a phycoerythrin (PE)-conjugated anti-ABL antibody is the detector reagent and mean fluorescence intensity (MFI) signals were recorded by flow cytometry. Detection of t(9;22)(q34;q11) translocation was carried out with a quantitative PCR assay. Results: MFI results of 20 normal peripheral blood samples were 88±8 (mean±SD), CV 9%. K562 cells were used as positive control. Within-batch imprecision was excellent (3.7% in the normal and 10% in the pathological range). Cut-off was chosen at MFI 112, where both sensitivity and specificity were 100%. Altogether 17 chronic myeloid leukemia (CML) and 16 acute leukemia samples were analyzed. All PCR positive samples (n=14) were positive with the FC method and negative results were also concordant (n=15). Frozen cell lysates can be stored up to 4 weeks without significant decrease of MFI signal. Conclusions: The FC BCR-ABL assay is a fast, reproducible and reliable method that may be incorporated into standard flow cytometric protocols to help clinical decision-making.

One hundred fifty autologous peripheral haemopoietic stem cell transplantations and their lessons

UNLABELLED Five years ago (in September, 2003), the activity of the 5th Haemopoietic Stem Cell Transplantation Centre of Hungary has begun. This centre has been registered as No 648. by the European Group for Blood and Marrow Transplantation-Centres. AIMS To supply the needs of stem cell transplantation regions in north-east Hungary and to develop an active co-operation with the Hungarian and international centres. METHODS Transplantations were made according to international criteria. RESULTS 150 autologous stem cell transplantations has been performed so far, including 74 patients with myeloma multiplex, 43 patients with non-Hodgkin lymphoma, 27 patients with Hodgkins disease, 4 patients with autoimmune disease, and one patient with leiomyosarcoma. The survival rates were similar to the previous Hungarian and international data. The centre played a role in other activities using stem cell therapy at the University of Debrecen (dendritic cell vaccine program, stem cell therapy in myocardial infarction, stem cell therapy in peripheral arterial- and autoimmune diseases). This centre performed the largest quantity of the conditioning protocol Zevalin, Bischloronitrosourea, Etoposide, cytosine-Arabinoside, Melphalan in non-Hodgkin lymphoma in Hungary; ten patients were treated with this protocol.

The pathophysiology, clinical signs and therapy of urate nephropathy

Tumor lysis syndrome is an oncologic emergency that is characterized by severe electrolyte abnormalities. The syndrome occurs in patients with lymphoproliferative malignancies, most often after chemotherapy, but also spontaneously. The pathophysiology involves tumor cell lysis resulting in the release of potassium, phosphate and uric acid. The deposition of uric acid and calcium phosphate crystals in the renal tubules may lead to acute renal failure. The treatment consists in hydration, correction of the acidosis and hyperkalemia, use of allopurinol and recombinant urate oxidase (rasburicase) for preventing urate nephropathy and haemodialysis. The authors report a case of a patient with acute myeloid leukemia, who developed severe tumor lysis syndrome after chemotherapy.

[Treatment of acute myeloid leukemia -- a single center experience (2007-2013)].

INTRODUCTION Mortality of acute myeloid leukemia is still 60-70% in young (<60 years) adults and 90% in elderly (≥60 years) patients. AIM The aim of the authors was to analyse the outcome of treatment in their patients with acute myeloid leukemia. METHOD From 2007 to 2013, 173 patients with acute myeloid leukemia were treated. Patients were classified according to the European LeukemiaNet prognostic guideline. Association between mortality and the type of acute myeloid leukemia (secondary or primary), dose of daunoblastin at induction of treatment, and the rate of minimal residual disease were investigated. RESULTS The 5-year survival probability was 25% in young adults and 2% in the elderly. The survival was significantly influenced by these prognostic factors. The 5-year survival rate was 50% in the young, favorable prognostic group. The 90 mg/m2 daunoblastin dose was found to be beneficial. Addition of bortezomib to the standard induction protocol had an additional beneficial effect. CONCLUSIONS The speed and depth of the response to induction therapy, and the initial white blood cell count had an apparent effect on survival.

Heveny myeloid leukaemiás betegeink kezelésével szerzett tapasztalataink (2007–2013)@@@Treatment of acute myeloid leukemia – a single center experience (2007–2013)

INTRODUCTION Mortality of acute myeloid leukemia is still 60-70% in young (<60 years) adults and 90% in elderly (≥60 years) patients. AIM The aim of the authors was to analyse the outcome of treatment in their patients with acute myeloid leukemia. METHOD From 2007 to 2013, 173 patients with acute myeloid leukemia were treated. Patients were classified according to the European LeukemiaNet prognostic guideline. Association between mortality and the type of acute myeloid leukemia (secondary or primary), dose of daunoblastin at induction of treatment, and the rate of minimal residual disease were investigated. RESULTS The 5-year survival probability was 25% in young adults and 2% in the elderly. The survival was significantly influenced by these prognostic factors. The 5-year survival rate was 50% in the young, favorable prognostic group. The 90 mg/m2 daunoblastin dose was found to be beneficial. Addition of bortezomib to the standard induction protocol had an additional beneficial effect. CONCLUSIONS The speed and depth of the response to induction therapy, and the initial white blood cell count had an apparent effect on survival.

Identification of NPMc+ acute myeloid leukemia in bone marrow smears

The most frequent genetic change currently known in acute myeloid leukemia (AML) is the mutation of the nucleophosmin (NPM) gene. Aberrant cytoplasmic accumulation of NPM protein (NPMc+) is the result of this mutation, and it can be demonstrated by immunohistochemistry for the identification of a favorable subgroup within “AML with normal karyotype” according to the World Health Organization classification. NPM staining pattern was defined in 71 AML and 15 control cases by the use of bone marrow smears in order to overcome limitations observed due to immunohistochemistry. In 13/71 cases (18.3%), clear cytoplasmic staining of the leukemic blast cells was detectable that was comparable with the positivity of mitotic figures physiologically lacking nuclear membrane. The biological and genetic characteristics of the NPMc+ cases determined this way were identical with the previously published results including low CD34 and HLA-DR expression and lack of recurrent karyotype abnormalities. Bone marrow smears are well applicable and therefore a real alternative for the determination of NPM with the highest accuracy for optimal risk stratification in AML.

Practical considerations and questions in the treatment of chronic lymphocytic leukemia

Understanding the pathogenesis and refine the treatment of chronic lymphocytic leukemia have been tremendously improved in the past decade. Treatment outcome and estimated prognosis have become more accurate due to the advanced molecular biological techniques and the classical prognostic markers. Incorporation of fludarabine and rituximab into the standard protocols fundamentally improved treatment outcome in chronic lymphocytic leukemia. Chemoimmunotherapy has improved not only the remission rates but had a significant impact on overall survival, as well. Eliminating residual leukemia and achieving complete hematological remissions at such high rates establish potential background for cure. Still, a great deal of dispute has been emerged regarding everyday clinical practice. Authors present their institutional experiences and review the literature.

Practical considerations and questions in the treatment of chronic lymphocytic leukemia: Irodalmi és saját tapasztalatokInstitutional experiences and review of the literature

Understanding the pathogenesis and refine the treatment of chronic lymphocytic leukemia have been tremendously improved in the past decade. Treatment outcome and estimated prognosis have become more accurate due to the advanced molecular biological techniques and the classical prognostic markers. Incorporation of fludarabine and rituximab into the standard protocols fundamentally improved treatment outcome in chronic lymphocytic leukemia. Chemoimmunotherapy has improved not only the remission rates but had a significant impact on overall survival, as well. Eliminating residual leukemia and achieving complete hematological remissions at such high rates establish potential background for cure. Still, a great deal of dispute has been emerged regarding everyday clinical practice. Authors present their institutional experiences and review the literature.