CD38-negative relapse in multiple myeloma after daratumumab-based chemotherapy.

We present a case report of a patient relapsing after anti-CD38 treatment (daratumumab). The phenotype of the disease changed during this treatment, and the myeloma clone became CD38 negative and daratumumab refractory. We expected clonal shift, however, based on immunophenotyping, cytogenetics and arrayCGH; the clone was identical as before daratumumab-based treatment with the exception of CD38 negativity. We suggest that the downregulation or loss of CD38 might be an epigenetic "escape mechanism" of malignant plasma cells from antibody-based treatment. The aim of our study was to point out the pitfalls of immunophenotyping and cytogenetics in both assessing the minimal residual disease and clone detection after monoclonal antibody-based therapy.

Mixed-phenotype acute leukemia: state-of-the-art of the diagnosis, classification and treatment.

Mixed-phenotype acute leukemia (MPAL) is a heterogeneous group of hematopoietic malignancies in which blasts show markers of multiple developmental lineages and cannot be clearly classified as acute myeloid or lymphoblastic leukemias. Historically, various names and classifications were used for this rare entity accounting for 2-5% of all acute leukemias depending on the diagnostic criterias used. The currently valid classification of myeloid neoplasms and acute leukemia published by the World Health Organization (WHO) in 2016 refers to this group of diseases as MPAL. Because adverse cytogenetic abnormalities are frequently present, MPAL is generally considered a disease with a poor prognosis. Knowledge of its treatment is limited to retrospective analyses of small patient cohorts. So far, no treatment recommendations verified by prospective studies have been published. The reported data suggest that induction therapy for acute lymphoblastic leukemia followed by allogeneic hematopoietic cell transplantation is more effective than induction therapy for acute myeloid leukemia or consolidation chemotherapy. The establishment of cooperative groups and international registries based on the recent WHO criterias are required to ensure further progress in understanding and treatment of MPAL. This review summarizes current knowledge on the diagnosis, classification, prognosis and treatment of MPAL patients.

Comparison of reduced conditionings combining fludarabine with melphalan or 3-day busulfan in patients allografted for myeloid neoplasms.

In the present study we compared outcomes of patients with myeloid neoplasms undergoing allogeneic hematopoietic stem cell transplantation after fludarabine-based regimens with melphalan (FM140) or 3-day busulfan (FB3). The FM140 and FB3 combinations were administered to 21 and 27 patients, respectively. Efforts for early reduction (from day +30 to 60) and discontinuation (until day +100 to 130) of prophylactic immunosuppression were a component of the post-transplant approach. Following FB3 patients suffered from more severe stomatitis (P = 0.013). In contrast, other manifestations of regimen-related toxicity were more frequent in the FM140 group (P = 0.048). There were no statistically significant differences in the development of graft-versus-host disease, non-relapse mortality, post-transplant remission rate, or relapse incidence. Two-year disease-free survival rates were comparable in the two cohorts (66 vs. 55 %; P = 0.751), and so were the overall survival rates (64 vs. 62 %; P = 0.715). The outcomes of allografted patients with myeloid neoplasms were comparable after the FM140 and FB3 regimens. Relatively high therapeutic response in both groups may have been influenced by early reduction and discontinuation of prophylactic immunosuppression followed by effective immunological control of the malignant clone.

Array-based karyotyping in chronic lymphocytic leukemia (CLL) detects new unbalanced abnormalities that escape conventional cytogenetics and CLL FISH panel.

AIMS: Chronic lymphocytic leukemia (CLL) is the most common adult leukemia with a very heterogeneous course. Progress in molecular genetic characterization of CLL has confirmed the prognostic role of unbalanced chromosomal abnormalities currently defined by molecular cytogenetic methods: conventional karyotyping and FISH. However, a significant percentage of genomic abnormalities escapes routine investigation due to the limitations of these methods. It is presently clear that some of these aberrations have impact on prognosis and disease progression. METHODS: We examined copy number changes in the tumor genomes of 50 CLL patients using bacterial artificial chromosome (BAC) and/or oligonucleotide array platforms. We compared the results of arrayCGH with those obtained by FISH and conventional cytogenetics and evaluated their clinical importance. RESULTS: A total of 111 copy number changes were detected in 43 patients (86%) with clonal abnormalities present in at least 23% of the cells. Moreover, 14 patients (28%) were found to have 39 genomic changes that had not been detected by standard cytogenetic and/or FISH analyses. These included possibly prognostically important recurrent 2p and 8q24 gains. The most frequent unbalanced changes involved chromosomes 18, 7, 3, 9 and 17. We also determined the minimal deleted region on chromosome 6q in 7 cases by chromosome 6/7 specific array. CONCLUSIONS: The results showed that a subset of potentially significant genomic aberrations in CLL is being missed by the current routine techniques. Further, we clearly demonstrated the robustness, high sensitivity and specificity of the arrayCGH analysis as well as its potential for use in routine screening of CLL.

Expression of miR-15a and miR-16-1 in patients with chronic lymphocytic leukemia.

INTRODUCTION: MicroRNAs (miRNAs) are small non-coding single-stranded RNA molecules that regulate gene expression at the post-transcriptional level. In the pathogenesis of chronic lymphocytic leukemia (CLL), miR-15a and miR-16-1 play an important role. These miRNAs are located on chromosome 13 in the 13q14.3 region, which is deleted in more than 55% of CLL patients. This aberration affects expression of miRNAs. OBJECTIVES: The study aimed at performing a molecular genetic analysis of miR-15a and miR-16-1 expression in a group of 39 patients diagnosed with CLL and determining the association between the expression of the two miRNAs and types of deletions in the 13q14 region. METHODS: We used fluorescence in situ hybridiziation (FISH) for determination of mono- or biallelic deletion 13q and quantitative polymerase chain reaction (Q-RT-PCR) to revealed expression miR-15a and miR-16-1 in 39 patients suffering from CLL. RESULTS: The analysis comprised 19 patients with monoallelic 13q14 deletion, 3 patients with biallelic deletion, 9 patients with both monoallelic and biallelic deletions, and 8 patients without 13q14 deletion serving as controls. The results showed different levels of miRNA expression in individual patients. Significantly higher normalized levels of miR-15a expression were found in the control group and patients with monoallelic 13q14 expression compared with patients with biallelic deletion. There was a significantly decreased expression of both miRNAs in patients with biallelic deletion of the 13q14 region but only when deletions were present in 77% or more of cells, as detected by fluorescent in situ hybridization (FISH).

Comparison of new flu-bu12-tg conditioning with the standard bu-cy myeloablative regimen in patients undergoing allogeneic stem cell transplantation for acute myeloid leukemia.

AIMS: This study compares the outcomes of patients with high-risk acute myeloid leukemia (AML) who underwent allogeneic stem cell transplantation (SCT) after conditioning combining busulfan (16 mg/kg orally) and cyclophosphamide (120 mg/kg intravenously) (BU-CY) with those allografted after administration of fludarabine (150 mg/m(2) intravenously), busulfan (12 mg/kg orally) and thymoglobulin (6 mg/kg intravenously) (FLU-BU12-TG). MATERIAL AND METHODS: SCT after BU-CY and FLU-BU12-TG was performed in 21 and 10 AML patients. There were no significant differences between groups in number of patients treated in complete disease remission, gender, age, donors, CD34+, mononuclear cell (MNC) count in the graft and follow-up period. However, significantly more SCTs from unrelated (90% vs. 19%; p=0.00018) and HLA-mismatched donors (50% vs. 0%; p=0.0004) were performed in the FLU-BU12-TG group. The Cox proportional hazards model was used to assess the risk of post-transplant AML relapse and non-relapse mortality (NRM). The probability of post-transplant 2-year event-free survival (EFS) and overall survival (OS) were calculated using the Kaplan-Meier method. RESULTS: No significant differences were found between the FLU-BU12-TG and BU-CY groups in risk of AML relapse (HR=1.036; 95% CI [0.102 - 10.47]; p=0.9), post-transplant NRM (HR=0.25; 95% CI [0.031 - 1.96]; p=0.18), 2-year EFS (89% vs. 43%; p=0.19) or OS (79% vs. 57%; p=0.23). CONCLUSION: These pilot results demonstrate the efficacy of the new FLU-BU12-TG conditioning regimen in patients allografted for high-risk AML. This conditioning might become an alternative approach in patients at high risk of severe post-transplant complications after the standard BU-CY myeloablative regimen.

Gain of chromosome 2p in chronic lymphocytic leukemia: significant heterogeneity and a new recurrent dicentric rearrangement.

Array-based comparative genomic hybridization (arrayCGH) studies in chronic lymphocytic leukemia (CLL) have revealed novel recurrent chromosomal imbalances, such as a gain of chromosome 2p. However, a detailed cytogenetic analysis of the 2p gain region has not been elucidated. Here, we present cytogenetic and molecular cytogenetic analysis of 16 such cases selected from a group of 200 patients with CLL based on CGH and/or arrayCGH data. We revealed significant heterogeneity of the region of gain on 2p in CLL, including a new recurrent aberration: the dicentric chromosome, dic(2;18). In our cases, the region of gain involved three genes (MYCN, REL, and ALK) and was associated with an unmutated IgVH status in 14 out of 16 cases. We consider this aberration clinically important in CLL and suggest that an examination of the gene(s) located in region of gain should be included in the routine fluorescence in situ hybridization screening method used for patients with CLL.

Rituximab does not adversely affect the stem cell mobilization and engraftment after high-dose therapy and autologous transplantation in patients with diffuse large B-cell lymphoma in first complete or partial remission.

AIMS AND METHODS: The goal was to investigate the effect of prior combined rituximab (R) and intensive chemotherapy on peripheral blood stem cell mobilization and their engraftment after stem cell transplantation (ASCT) in 69 patients with poor-risk, diffuse large B-cell lymphoma (DLBCL). RESULTS: A statistically comparable median number of CD34+ stem cells was collected in both groups (13.80x10(6)/ kg in the non-R group and 7.81x10(6)/kg in the R group; p = 0.110). A trend toward greater number of CFU-GM was found in the non-R group (98.1x10(4)/kg) compared to the R group (76.6x10(4)/kg; p = 0.068). The non-R patients had a much higher median number of BFU-E (90.9x10(4)/kg) than the R patients (31.3x10(4)/kg; p = 0.001). CONCLUSIONS: Hematopoietic engraftment was rapid for both groups and no different between them. The 3-year event-free survival was 90.4 % in the R group and 67.2 % in the non-R group (p = 0.04), but there was no significant difference in the 3-year overall survival (94,7 % vs 83,5 %; p = 0.179).

Precursor T-lymphoblastic lymphoma as a secondary malignancy in a young patient after successful treatment of acute promyelocytic leukemia.

BACKGROUND: Acute promyelocytic leukemia (APL) is a relatively rare subtype of acute myeloid leukemia. It has become the best curable subtype of acute leukemias in adults due to the inclusion of all-trans-retinoic acid (ATRA) in the treatment. Despite the efficacy of ATRA, chemotherapy must be added in APL patients in order to maintain durable complete remission. However, chemotherapy administration is inevitably related to many complications, including the risk of secondary malignancies. T-lymphoblastic lymphoma (T-LBL) is an infrequent disease that belongs to the group of highly aggressive lymphomas. CASE REPORT: The authors describe the case of a 25-year-old woman who was treated for APL in 2002 and developed precursor T-LBL 5 years later. CONCLUSION: Several cases of secondary acute lymphoblastic leukemias in 'cured' APL patients have been described, but probably no patient with secondary precursor T-LBL. Secondary malignancy has become one of the topics discussed (not only) in APL patients. It is apparently related to the excellent treatment outcomes and long-term survival. Better tailored treatment based on relevant prognostic factors allowing chemotherapy reduction or omission in some patients is needed.

Immunophenotyping--a tool for the differential diagnostics of lymphadenomegaly.

BACKGROUND: Flow cytometry is a method that enables the automated quantification of a set of parameters for a large number of cells or cell-like particles. It is also possible to analyze solid tissues after reduction to a single cell suspension. One of the applications of fl ow cytometry is immunophenotyping. AIM: The authors try to introduce the basic physical and biological principles of fl ow-cytometry to the broader public and to prove the benefits of method in lymph nodes assessment. METHOD: A common method of immunophenotyping with the help of labeled monoclonal antibodies applied to lymph node cells was used. RESULTS: Flow cytometry revealed the infiltration of the extirpated lymph node with leukemic cells. CONCLUSIONS: The authors demonstrate fl ow cytometry as a relatively less common but efficient way of lymph node assessment in a patient with an anamnesis of acute lymphoblastic leukemia. They also discuss the contribution of immunophenotyping to the process of the differential diagnostics of lymph nodes enlargement.

Spontaneous splenic rupture in two patients with hematologic malignancy.

BACKGROUND: Spontaneous splenic rupture (SSR) is a very rare complication described in several hundred patients, mainly as case reports. It is defined as a splenic rupture without antecedent injury. The authors of the present paper describe the only two SSR cases diagnosed at the Hemato-oncology department, coincidentally in one year. PATIENTS: The first patient was admitted to hospital because of planned chemotherapy for relapsed hairy cell leukemia. The second was directed to the Hemato-oncology outpatient department because of anemia and painful splenomegaly diagnosed by a physician. The diagnose of hematologic malignancy (diffuse large B-cell lymphoma) was determined subsequently on the basis of histological examination of the spleen. CONCLUSION: It is necessary to consider SSR not only in patients with known diagnosis of malignant disease but in the patients with negative anamnesis, too. The aim of the paper is to draw attention to the existence of this complication.

T-cell gamma/delta hepatosplenic lymphoma - prolonged remission induced by aggressive first line treatment.

T-cell gamma/delta hepatosplenic lymphoma is a primary extranodal lymphoma, distinct from other T/LGL lymphomas. The clinical course is aggressive, and despite use of the multiagent chemotherapy and young age of the patients, the median survival is less than 1 year. Curability of this disease is still uncertain. We reported a case of the successful intensive treatment with splenectomy, chemotherapy a first line autologous stem cell transplant. High intensity cytarabine- platinum containing regimen (EDHAP) may overcome primary resistance to conventional alkylating agents.