International Working Group consensus response evaluation criteria in lymphoma (RECIL 2017).

In recent years, the number of approved and investigational agents that can be safely administered for the treatment of lymphoma patients for a prolonged period of time has substantially increased. Many of these novel agents are evaluated in early-phase clinical trials in patients with a wide range of malignancies, including solid tumors and lymphoma. Furthermore, with the advances in genome sequencing, new "basket" clinical trial designs have emerged that select patients based on the presence of specific genetic alterations across different types of solid tumors and lymphoma. The standard response criteria currently in use for lymphoma are the Lugano Criteria which are based on [18F]2-fluoro-2-deoxy-D-glucose positron emission tomography or bidimensional tumor measurements on computerized tomography scans. These differ from the RECIST criteria used in solid tumors, which use unidimensional measurements. The RECIL group hypothesized that single-dimension measurement could be used to assess response to therapy in lymphoma patients, producing results similar to the standard criteria. We tested this hypothesis by analyzing 47 828 imaging measurements from 2983 individual adult and pediatric lymphoma patients enrolled on 10 multicenter clinical trials and developed new lymphoma response criteria (RECIL 2017). We demonstrate that assessment of tumor burden in lymphoma clinical trials can use the sum of longest diameters of a maximum of three target lesions. Furthermore, we introduced a new provisional category of a minor response. We also clarified response assessment in patients receiving novel immune therapy and targeted agents that generate unique imaging situations.

T-cells fighting B-cell lymphoproliferative malignancies: the emerging field of CD19 CAR T-cell therapy.

CAR T-cells are autologous T-cells transduced with a chimeric antigen receptor (CAR). The CAR contains an antigen recognition part (originating from an antibody), a T-cell receptor transmembrane and cytoplasmic signalling part, and one or more co-stimulatory domains. While CAR T-cells can be directed against any tumour target, most experience thus far has been obtained with targeting of the B-cell antigen CD19 that is expressed by B-cell acute lymphocytic leukaemia, chronic lymphocytic leukaemia and other B-cell lymphomas. The first clinical results are promising, although there are profound differences in response between patients with different haematological malignancies. Treatment-related side effects have been observed that require specific management. This review will explain the mechanism of action, summarise the experience to date and point out future directions for this hopeful new addition to the therapeutic armamentarium in the treatment of lymphoproliferative B-cell malignancies.

CD20-targeted therapy: a breakthrough in the treatment of non-Hodgkin's lymphoma.

Targeting the CD20 antigen on B lymphocytes with the monoclonal antibody rituximab has greatly improved the outcome of patients with B-cell malignancies. Despite the success of rituximab, resistance occurs in about half of the patients, resulting in non-response to treatment or early relapse of the original disease. A better understanding of the mechanism of rituximab resistance has lead to the development of novel, improved anti-CD20 antibodies. This review describes the development of CD20-targeted therapy from its historical background towards the next generation of anti-CD20 monoclonal antibodies and explains new strategies to overcome resistance.

Immunohistochemical prognostic markers in diffuse large B-cell lymphoma: validation of tissue microarray as a prerequisite for broad clinical applications (a study from the Lunenburg Lymphoma Biomarker Consortium).

BACKGROUND AND AIMS: The results of class prediction and the determination of prognostic markers in diffuse large B-cell lymphoma (DLBCL) have been variably reported. Apart from biological variations, this may be caused by differences in laboratory techniques, scoring definitions and inter- and intra-observer variation. In this study, an international collaboration of clinical lymphoma research groups has concentrated on validation and standardisation of immunohistochemistry of the currently potentially interesting prognostic markers in DLBCL. METHODS: Sections of a tissue microarray with 36 cases of DLBCL were stained in eight laboratories with antibodies to CD20, CD5, bcl-2, bcl-6, CD10, HLA-DR, MUM-1 and Ki-67 according to local methods. The study was performed in two rounds, firstly focused on the evaluation of laboratory staining variation, and secondly on the scoring variation. RESULTS: Different techniques resulted in highly variable results and poor reproducibility for almost all markers. Reproducibility of the nuclear markers was highly sensitive to technical variations, including immunological enhancement techniques (agreements 34%). With elimination of variation due to staining and uniformly agreed on scoring criteria, significant improvement was seen; however less so for bcl-6 and Ki-67 (agreement 53-58%). Absence of internal controls that preclude scoring, significantly influenced the results for CD10 and bcl-6. CONCLUSION: Semi-quantitative immunohistochemistry for subclassification of DLBCL is feasible, but with varying rates of concordance for different markers and only using optimised techniques and strict scoring criteria. These findings may explain the wide variation in prognostic impact reported in the literature. Harmonisation of techniques and centralised consensus review appears mandatory when using immunohistochemical biomarkers for treatment stratification.

The CD20/alphaCD20 'suicide' system: novel vectors with improved safety and expression profiles and efficient elimination of CD20-transgenic T cells.

Adoptive transfer of T lymphocytes is an attractive strategy for many experimental treatment strategies for cancer. Unfortunately, manipulated T cells could be responsible for serious adverse events. Retroviral CD20-transduced T cells may be able to control these unwanted effects. CD20-positive cells are sensitive to rituximab (RTX), a monoclonal antibody specific for CD20. This permits their selective elimination in vivo in case of adverse events. To this end, a system is required that permits efficient and safe transduction of donor T cells and effective elimination of CD20-positive T cells. We constructed different CD20-encoding retroviral vectors and investigated the impact of inclusion of the woodchuck post-transcriptional regulatory element (WPRE) and the chicken hypersensitivity site 4 insulator elements on the levels, homogeneity and stability of CD20 expression. Importantly, inclusion of either WPRE or insulator elements in the retroviral vector resulted in a dramatic improvement in the stability of CD20 expression. The insulator element also led to a much more homogeneous level of CD20 expression. We also show the efficient elimination of the CD20-transgenic T cells via RTX by different effector mechanisms. In conclusion, we have constructed CD20-encoding retroviral vectors with improved efficiency and safety profiles, which can be used as a suicide strategy.

T cell receptor-transgenic primary T cells as a tool for discovery of leukaemia-associated antigens.

Identification of a broad array of leukaemia-associated antigens is a crucial step towards immunotherapy of haematological malignancies. However, it is frequently hampered by the decrease of proliferative potential and functional activity of T cell clones used for screening procedures. Transfer of the genes encoding the T cell receptor (TCR) alpha and beta chains of leukaemia-specific clones into primary T cells may help to circumvent this obstacle. In this study, transfer of two minor histocompatibility antigen (minor H antigen)-specific TCRs was performed and the feasibility of the use of TCR-transgenic T cells for identification of minor H antigens through cDNA library screening was investigated. We found that TCR-transgenic cells acquired the specificity of the original clones and matched their sensitivity. Moreover, the higher scale of cytokine-production by TCR-transgenic T cells permits the detection of either small amounts of antigen-positive cells or cells expressing low amounts of an antigen. When applied in equal numbers, TCR-transgenic T cells and the original T cell clones produced similar results in the screening of a cDNA library. However, the use of increased numbers of TCR-transgenic T cells allowed detection of minute amounts of antigen, barely discernible by the T cell clone. In conclusion, TCR-transfer generates a large amount of functional antigen-specific cells suitable for screening of cDNA expression libraries for identification of cognate antigens.

B-cell expansion in the presence of the novel 293-CD40L-sCD40L cell line allows the generation of large numbers of efficient xenoantigen-free APC.

BACKGROUND: CD40-activated B lymphocytes have been used successfully as potent APC for the induction of T-cell responses. However, the 3T3-CD40L cell line, regularly used for engagement of CD40 on the B-cell surface, is a potential source of xenoantigens. This may affect the specificity of T cells stimulated with CD40-activated B cells, especially when generation of T-cell lines specific for endogenously processed Ag is desired. METHODS: To develop a system that allows efficient expansion of B cells in the absence of sources of xenoantigens, we created a human 293-CD40L-sCD40L cell line that produces soluble CD40L and expresses CD40L on the cell surface. B cells from patients with hematologic malignancies were expanded on the 293-CD40L-sCD40L cells and used for stimulation of either naive or in vivo primed donor T cells in three HLA-identical patient-donor combinations. RESULTS: The 293-CD40L-sCD40L cell line was able to stimulate B-cell growth with an efficiency superior to that of the commonly used 3T3-CD40L cell line. In all cases T-cell lines and, subsequently, T-cell clones were generated that showed reactivity against patient and not donor B cells, suggesting their specificity for minor histocompatibility antigens (mHAg). DISCUSSION: B cells activated with GMP grade 293-CD40L-sCD40L can be used in a variety of applications. In particular, they may be suitable for ex vivo stimulation of T cells prior to donor lymphocyte infusion (DLI), which may enhance its graft versus leukemia (GvL) effect.

Report of a European consensus workshop to develop recommendations for the optimal use of (90)Y-ibritumomab tiuxetan (Zevalin) in lymphoma.

BACKGROUND: Non-Hodgkin's lymphoma (NHL) comprises a group of related haematological malignancies, predominantly of B-cell origin, which have been described as indolent or aggressive according to their clinical course. Standard treatment for indolent NHL consists of conventional chemotherapy, but, although long-term remissions may occur, most patients will die of their disease. Radioimmunotherapy (RIT) is a novel modality for treating indolent NHL, using monoclonal antibodies to target tumour cells with systemic, low-dose radiation. (90)Y-Ibritumomab tiuxetan (Zevalin); Schering AG, Berlin, Germany), the first RIT approved for use in relapsed/refractory indolent NHL, comprises the murine anti-CD20 monoclonal antibody ibritumomab, covalently linked to the high-energy beta-emitter, yttrium-90, by the chelator, tiuxetan. MATERIALS AND METHODS: A multidisciplinary consensus workshop of European clinicians who had taken part in clinical trials of (90)Y-ibritumomab tiuxetan was convened to develop recommendations for the clinical preparation and administration of (90)Y-ibritumomab tiuxetan in Europe. The workshop was held in anticipation of European Medicines Agency approval of this agent, which was gained in 2004 for adult patients with rituximab-relapsed or refractory CD20(+) follicular B-cell NHL. RESULTS AND CONCLUSIONS: This article summarises the consensus recommendations developed for hemato-oncologists.

Meta-analysis to evaluate the role of interferon in follicular lymphoma.

PURPOSE: To determine whether interferon (IFN) -alpha2, when given with or following chemotherapy, influences response rate, remission duration, and survival in newly diagnosed patients with follicular lymphoma. PATIENTS AND METHODS: Ten phase III studies evaluating the role of IFN-alpha2 in 1,922 newly diagnosed patients with follicular lymphoma were analyzed. Updated individual patient data were used to perform meta-analyses for response, survival, and remission duration. RESULTS: The addition of IFN-alpha2 to initial chemotherapy did not significantly influence response rate. An overall meta-analysis for survival showed a significant difference in favor of IFN-alpha2, but also showed significant heterogeneity between studies. Further analyses were carried out in order to explain this heterogeneity, and to define the circumstances in which IFN-alpha2 prolonged survival. The survival advantage was seen when IFN-alpha2 was given: (1) in conjunction with relatively intensive initial chemotherapy (2P = .00005), (2) at a dose >/= 5 million units (2P = .000002), (3) at a cumulative dose >/= 36 million units per month (2P = .000008), and (4) with chemotherapy rather than as maintenance therapy (P = .004). With regard to remission duration, there was also a significant difference in favor of IFN-alpha2, irrespective of the intensity of chemotherapy used, IFN dose, or whether IFN was given as a maintenance strategy or with chemotherapy. CONCLUSION: When given in the context of relatively intensive initial chemotherapy, and at a dose >/= 5 million units (>/= 36 x 10(6) units per month), IFN-alpha2 prolongs survival and remission duration in patients with follicular lymphoma.

Prevalence and clinical significance of resistance to perforin- and FAS-mediated cell death in leukemia.

Killer lymphocytes play a central therapeutic role in graft-versus-leukemia following allogeneic hematopoietic stem cell transplantation (HSCT). The Perforin/Granzyme and FAS/CD95 pathways are of crucial importance in tumor cell elimination by killer cells. In this study, we have examined whether hematological malignancies are resistant to perforin and anti-FAS antibodies. Leukemic cells were studied from 29 patients suffering either from acute or chronic myeloid leukemia (AML or CML), acute or chronic lymphoid leukemia, or non-Hodgkin's lymphoma. An average of 49 vs 5% of specific cell killing was found when using perforin vs anti-FAS antibodies, respectively. Interestingly, resistance towards both perforin and anti-FAS antibodies was found exclusively in leukemic cells from patients with myeloid leukemia. Analysis of leukemic cells from patients with CML, suffering from leukemia relapse after HSCT and given donor lymphocyte infusion (DLI) to induce remission, indicated that the effectiveness of treatment with DLI was not associated with sensitivity of leukemic cells to perforin. In conclusion, resistance towards anti-FAS antibodies is a common phenomenon in leukemia/lymphoma, whereas perforin resistance occurs only in myeloid leukemia. However, as a single parameter, perforin resistance does not appear to be suitable to predict the outcome of DLI.

Genetic marking with the DeltaLNGFR-gene for tracing goat cells in bone tissue engineering.

The use of bone marrow derived stromal cells (BMSC's) for bone tissue engineering has gained much attention as an alternative for autologous bone grafting. Little is known however, about the survival and differentiation of the cells, especially in the clinical application. The aim of this study was to develop a method to trace goat BMSC's in vivo. We investigated retroviral genetic marking, which allows stable expression of the label with cell division. Goat BMSC's were subjected to an amphotropic envelope containing a MoMuLV-based vector expressing the human low affinity nerve growth factor receptor (DeltaLNGFR). Labeling efficiency and effect on the cells were analyzed. Furthermore, transduced cells were seeded onto porous ceramic scaffolds, implanted subcutaneously in nude mice and examined after successive implantation periods. Flow cytometry indicated a transduction efficiency of 40-60%. Immunohistochemistry showed survival and subsequent bone formation of the gene-marked cells in vivo. Besides, marked cells were also found in cartilage and fibrous tissue. These findings indicate the maintenance of the precursor phenotype following gene transfer as well as the ability of the gene to be expressed following differentiation. We conclude that retroviral gene marking with DeltaLNGFR is applicable to trace goat BMSC's in bone tissue engineering research.

G3139, a Bcl-2 antisense oligodeoxynucleotide, induces clinical responses in VAD refractory myeloma.

Expression of Bcl-2 in multiple myeloma is associated with resistance to chemotherapeutic drugs. Conversely, suppression of Bcl-2 enhanced the chemosensitivity of myeloma cells in vitro. G3139 is an antisense oligodeoxynucleotide targeted to the first six codons of the Bcl-2 mRNA open reading frame. In this study, G3139 was delivered as a continuous intravenous infusion for 7 days at a fixed dose of 7 mg/kg/day in combination with VAD (vincristine, adriamycin, and dexamethasone) chemotherapy. In total, 10 heavily pretreated patients with refractory myeloma participated in this trial, including eight patients with VAD refractory disease. The combination of G3139 and VAD was feasible and well tolerated. Seven patients (70%) responded including four patients (40%) with a partial response and three patients (30%) with a minor response. Median progression-free survival was 6 months (range, 2-7+ months) and median overall survival has not been reached. G3139 downregulated Bcl-2 protein levels in peripheral blood circulating myeloma cells, B cells, T cells, and monocytes. These results indicate that G3139 may overcome classical resistance and restore sensitivity of myeloma tumor cells to VAD chemotherapy.

Human primary T lymphocytes have a low capacity to amplify MLV-based amphotropic RCR and the virions produced are largely noninfectious.

The presence of replication-competent retrovirus (RCR) in retroviral-based gene therapy products poses a potential safety risk for patients. Therefore, RCR testing of clinical gene therapy products and monitoring of patients enrolled in gene therapy trials is required to assure viral safety. The requirement to test ex vivo-transduced cells originates from the presumed amplification of adventitious RCR during the transduction procedure. However, data on the capacity of different cell types to do so are lacking. In this study, we sought to analyze the amplification potential of primary human T lymphocytes after infection with amphotropic MLV-based RCR. The total number of viral particles produced after 1 or 2 weeks was measured by a quantitative 4070A env-specific RT-PCR assay. The fraction of infectious replication-competent viral particles was analyzed in the PG-4 S+L- assay. From this study, we conclude that the total number of viral particles RCR produced by T lymphocytes is 2-4 logs lower than the number produced by NIH-3T3 cells. Surprisingly, less than 1% of the viral particles produced by primary T lymphocytes appeared to be infectious, while nearly all virions produced by NIH-3T3 were. We conclude that primary human T lymphocytes are low producers of MLV-based amphotropic RCR.

Neutropenia and agranulocytosis in England and Wales: incidence and risk factors.

The objectives of this study were to estimate the incidence of idiosyncratic neutropenia and agranulocytosis in England and Wales and to evaluate their risk factors and outcomes. The study was conducted using data from the General Practice Research Database. All cases of idiosyncratic neutropenia or agranulocytosis were identified and the incidence was estimated. This was followed by a nested case-control study, estimating odds ratios with drug exposure from conditional logistic regression. From 1987 to 1999, 3,224 patients with idiosyncratic neutropenia (50 with agranulocytosis) were identified. The incidences of neutropenia and agranulocytosis were estimated to be 120 and 7 cases per million people per year, respectively. The adjusted odds ratios for neutropenia were 34.7 (95% confidence interval 12.0-99.7) for current users of thyroid inhibitors, 9.5 (4.4-20.8) for users of disease-modifying antirheumatic drugs, and 7.6 (4.9-11.9) for users of aminosalicylates. Other drugs with statistically significantly increased risks of neutropenia included antibacterial drugs, non-opioid analgesics, NSAIDs, antidepressants, ulcer-healing drugs, and anti-epileptics. The increase in risk of neutropenia predominantly occurred during the first months of treatment. For most drugs investigated in this study, there was no relationship to daily dose. The excess 1-year mortality was low among neutropenia and agranulocytosis cases and mostly explained by the underlying disease state. In conclusion, the highest risks of neutropenia were generally found in patients starting treatment. The excess 1-year mortality was low among neutropenia and agranulocytosis cases and can be mostly explained by the underlying disease state.

Editorial perspective--advances in B-cell non-Hodgkin's lymphoma.

Radioimmunotherapy (RIT) represents an exciting new therapeutic option for the treatment of B-cell non-Hodgkin's lymphoma (NHL), emerging at a time when significant advances have been made in NHL classification, molecular genetics and treatment. Despite recent treatment advances, including the use of fludarabine phosphate-based combination chemotherapies, able to eradicate minimal residual disease, there remains much room for improvement. The incorporation of RIT into treatment schedules is an attractive option to exploit the extreme sensitivity of lymphoma cells to irradiation. In this supplement, we examine the potential future roles for RIT in the light of past and present therapies, existing RIT clinical data and the unique attributes of radiolabeled monoclonal antibodies.

Cost analysis of HLA-identical sibling and voluntary unrelated allogeneic bone marrow and peripheral blood stem cell transplantation in adults with acute myelocytic leukaemia or acute lymphoblastic leukaemia.

Allogeneic stem cell transplantation (SCT) is one of the most expensive medical procedures. However, only a few studies to date have addressed the costs of HLA-identical sibling transplantation and only one study has reported costs of unrelated transplantation. No recent cost analysis with a proper follow-up period and donor identification expenses is available on related or voluntary matched unrelated donor (MUD) SCT for adult AML or ALL. Therefore, we calculated direct medical (hospital) costs based on 97 adults who underwent HLA-identical sibling bone marrow transplantation (BMT) or peripheral blood stem cell transplantation (PBSCT), and patients who received a graft from a MUD between 1994 and 1999. The average costs per transplanted patient were Euro 98,334 (BMT), Euro 151,754 (MUD), and Euro 98,977 (PBSCT), including donor identification expenses, 2 years follow-up and costs of patients who were not transplanted after they had been planned to receive an allograft. The majority of these costs was generated during the hospitalisation for graft infusion. For MUD transplants, nearly one-third of these costs was spent on the search for a suitable donor. For patients who were alive after 2 years, cumulative expenses were calculated to be Euro 103,509 (BMT), Euro 173,587 (MUD), and Euro 105,906 (PBSCT).