Risk factors for graft-versus-host-disease after donor lymphocyte infusion following T-cell depleted allogeneic stem cell transplantation.

Introduction: Unmodified donor lymphocyte infusions (DLI) after allogeneic stem cell transplantation (alloSCT) can boost the beneficial Graft-versus-Leukemia (GvL) effect but may also induce severe Graft-versus-Host-Disease (GvHD). To improve the balance between GvL and GvHD, it is crucial to identify factors that influence the alloreactivity of DLI. Methods: We investigated the effects of the presence of patient-derived antigen-presenting cells at time of DLI as estimated by the bone marrow (BM) chimerism status, lymphopenia as measured by the absolute lymphocyte count (ALC) at time of DLI, and the presence of a viral infection (de novo or reactivation) close to DLI on the risk of GvHD after DLI. The cohort consisted of patients with acute leukemia or myelodysplastic syndrome who prophylactically or pre-emptively received DLI as standard care after alemtuzumab-based alloSCT. In patients at high risk for relapse, DLI was administered at 3 months after alloSCT (n=88) with a dose of 0.3x106 or 0.15x106 T cells/kg in case of a related or unrelated donor, respectively. All other patients (n=76) received 3x106 or 1.5x106 T cells/kg, respectively, at 6 months after alloSCT. Results: For both DLIs, patients with reduced-intensity conditioning and an unrelated donor had the highest risk of GvHD. For DLI given at three months, viral infection within 1 week before and 2 weeks after DLI was an additional significant risk factor (hazard ratio (HR) 3.66 compared to no viral infection) for GvHD. At six months after alloSCT, viral infections were rare and not associated with GvHD. In contrast, mixed BM chimerism (HR 3.63 for ≥5% mixed chimerism compared to full donor) was an important risk factor for GvHD after DLI given at six months after alloSCT. ALC of <1000x106/l showed a trend for association with GvHD after this DLI (HR 2.05 compared to ≥1000x106/l, 95% confidence interval 0.94-4.45). Furthermore, the data suggested that the presence of a viral infection close to the DLI at three months or ≥5% mixed chimerism at time of the DLI at six months correlated with the severity of GvHD, thereby increasing their negative impact on the current GvHD-relapse-free survival. Conclusion: These data demonstrate that the risk factors for GvHD after DLI depend on the setting of the DLI.

Joint models quantify associations between immune cell kinetics and allo-immunological events after allogeneic stem cell transplantation and subsequent donor lymphocyte infusion.

Alloreactive donor-derived T-cells play a pivotal role in alloimmune responses after allogeneic hematopoietic stem cell transplantation (alloSCT); both in the relapse-preventing Graft-versus-Leukemia (GvL) effect and the potentially lethal complication Graft-versus-Host-Disease (GvHD). The balance between GvL and GvHD can be shifted by removing T-cells via T-cell depletion (TCD) to reduce the risk of GvHD, and by introducing additional donor T-cells (donor lymphocyte infusions [DLI]) to boost the GvL effect. However, the association between T-cell kinetics and the occurrence of allo-immunological events has not been clearly demonstrated yet. Therefore, we investigated the complex associations between the T-cell kinetics and alloimmune responses in a cohort of 166 acute leukemia patients receiving alemtuzumab-based TCD alloSCT. Of these patients, 62 with an anticipated high risk of relapse were scheduled to receive a prophylactic DLI at 3 months after transplant. In this setting, we applied joint modelling which allowed us to better capture the complex interplay between DLI, T-cell kinetics, GvHD and relapse than traditional statistical methods. We demonstrate that DLI can induce detectable T-cell expansion, leading to an increase in total, CD4+ and CD8+ T-cell counts starting at 3 months after alloSCT. CD4+ T-cells showed the strongest association with the development of alloimmune responses: higher CD4 counts increased the risk of GvHD (hazard ratio 2.44, 95% confidence interval 1.45-4.12) and decreased the risk of relapse (hazard ratio 0.65, 95% confidence interval 0.45-0.92). Similar models showed that natural killer cells recovered rapidly after alloSCT and were associated with a lower risk of relapse (HR 0.62, 95%-CI 0.41-0.93). The results of this study advocate the use of joint models to further study immune cell kinetics in different settings.

Competitive Repopulation and Allo-Immunologic Pressure Determine Chimerism Kinetics after T Cell-Depleted Allogeneic Stem Cell Transplantation and Donor Lymphocyte Infusion.

After allogeneic stem cell transplantation (alloSCT), patient-derived stem cells that survived the pretransplantation conditioning compete with engrafting donor stem cells for bone marrow (BM) repopulation. In addition, donor-derived alloreactive T cells present in the stem cell product may favor establishment of complete donor-derived hematopoiesis by eliminating patient-derived lymphohematopoietic cells. T cell-depleted alloSCT with sequential transfer of potentially alloreactive T cells by donor lymphocyte infusion (DLI) provides a unique opportunity to selectively study how competitive repopulation and allo-immunologic pressure influence lymphohematopoietic recovery. This study aimed to determine the relative contribution of competitive repopulation and donor-derived anti-recipient alloimmunologic pressure on the establishment of lymphohematopoietic chimerism after alloSCT. In this retrospective cohort study of 281 acute leukemia patients treated according to a protocol combining alemtuzumab-based T cell-depleted alloSCT with prophylactic DLI, we investigated engraftment and quantitative donor chimerism in the BM and immune cell subsets. DLI-induced increase of chimerism and development of graft-versus-host disease (GVHD) were analyzed as complementary indicators for donor-derived anti-recipient alloimmunologic pressure. Profound suppression of patient immune cells by conditioning sufficed for sustained engraftment without necessity for myeloablative conditioning or development of clinically significant GVHD. Although 61% of the patients without any DLI or GVHD showed full donor chimerism (FDC) in the BM at 6 months after alloSCT, only 24% showed FDC in the CD4+ T cell compartment. In contrast, 75% of the patients who had received DLI and 83% of the patients with clinically significant GVHD had FDC in this compartment. In addition, 72% of the patients with mixed hematopoiesis receiving DLI converted to complete donor-derived hematopoiesis, of whom only 34% developed clinically significant GVHD. Our data show that competitive repopulation can be sufficient to reach complete donor-derived hematopoiesis, but that some alloimmunologic pressure is needed for the establishment of a completely donor-derived T cell compartment, either by the development of GVHD or by administration of DLI. We illustrate that it is possible to separate the graft-versus-leukemia effect from GVHD, as conversion to durable complete donor-derived hematopoiesis following DLI did not require induction of clinically significant GVHD.

Light Therapy for Cancer-Related Fatigue in (Non-)Hodgkin Lymphoma Survivors: Results of a Randomized Controlled Trial.

PURPOSE: To evaluate the short- and long-term effects of light therapy on fatigue (primary outcome) and sleep quality, depression, anxiety, quality of life, and circadian rhythms (secondary outcomes) in survivors of (non-)Hodgkin lymphoma presenting with chronic cancer-related fatigue. METHODS: We randomly assigned 166 survivors (mean survival 13 years) to a bright white light intervention (BWL) or dim white light comparison (DWL) group. Measurements were completed at baseline (T0), post-intervention (T1), at three (T2), and nine (T3) months follow-up. A mixed-effect modeling approach was used to compare linear and non-linear effects of time between groups. RESULTS: There were no significant differences between BWL and DWL in the reduction in fatigue over time. Both BWL and DWL significantly (p < 0.001) improved fatigue levels during the intervention followed by a slight reduction in this effect during follow-up (EST0-T1 = -0.71; EST1-T3 = 0.15). Similar results were found for depression, sleep quality, and some aspects of quality of life. Light therapy had no effect on circadian rhythms. CONCLUSIONS: BWL was not superior in reducing fatigue compared to DWL in HL and DLBCL survivors. Remarkably, the total sample showed clinically relevant and persistent improvements on fatigue not commonly seen in longitudinal observational studies in these survivors.

A randomised, open-label trial to assess the optimal treatment strategy in early diffuse cutaneous systemic sclerosis: the UPSIDE study protocol.

INTRODUCTION: Systemic sclerosis (SSc) is a chronic, autoimmune connective tissue disease associated with high morbidity and mortality, especially in diffuse cutaneous SSc (dcSSc). Currently, there are several treatments available in early dcSSc that aim to change the disease course, including immunosuppressive agents and autologous haematopoietic stem cell transplantation (HSCT). HSCT has been adopted in international guidelines and is offered in current clinical care. However, optimal timing and patient selection for HSCT are still unclear. In particular, it is unclear whether HSCT should be positioned as upfront therapy or rescue treatment for patients refractory to immunosuppressive therapy. We hypothesise that upfront HSCT is superior and results in lower toxicity and lower long-term medical costs. Therefore, we propose this randomised trial aiming to determine the optimal treatment strategy for early dcSSc by comparing two strategies used in standard care: (1) upfront autologous HSCT versus (2) immunosuppressive therapy (intravenous cyclophosphamide pulse therapy followed by mycophenolate mofetil) with rescue HSCT in case of treatment failure. METHODS AND ANALYSIS: The UPSIDE (UPfront autologous hematopoietic Stem cell transplantation vs Immunosuppressive medication in early DiffusE cutaneous systemic sclerosis) study is a multicentre, randomised, open-label, controlled trial. In total, 120 patients with early dcSSc will be randomised. The primary outcome is event-free survival at 2 years after randomisation. Secondary outcomes include serious adverse events, functional status and health-related quality of life. We will also evaluate changes in nailfold capillaroscopy pattern, pulmonary function, cardiac MR and high-resolution CT of the chest. Follow-up visits will be scheduled 3-monthly for 2 years and annually in the following 3 years. ETHICS AND DISSEMINATION: The study was approved by the Dutch Central Committee on Research Concerning Human Subjects (NL72607.041.20). The results will be disseminated through patient associations and conventional scientific channels. TRIAL REGISTRATION NUMBERS: NCT04464434; NL 8720.

Autologous stem cell transplantation for progressive systemic sclerosis: a prospective non-interventional study from the European Society for Blood and Marrow Transplantation Autoimmune Disease Working Party.

Three randomized controlled trials in early severe systemic sclerosis demonstrated that autologous hematopoietic stem cell transplantation was superior to standard cyclophosphamide therapy. This European Society for Blood and Marrow Transplantation multi-center prospective non-interventional study was designed to further decipher efficacy and safety of this procedure for severe systemic sclerosis patients in real-life practice and to search for prognostic factors. All consecutive adult systemic sclerosis patients undergoing a first autologous hematopoietic stem cell transplantation between December 2012 and February 2016 were prospectively included in the study. Primary endpoint was progression free survival. Secondary endpoints were overall survival, non-relapse mortality, response and incidence of progression. Eighty systemic sclerosis patients were included. Median follow-up duration was 24 (6-57) months after stem cell transplantation using cyclophosphamide plus antithymocyte globulins conditioning for all, with CD34+ selection in 35 patients. At 2 years, progression free survival was 81.8%, overall survival was 90%, response was 88.7% and incidence of progression was 11.9%. The 100 days non-relapse mortality was 6.25% (n=5) with four deaths from cardiac event, including three due to cyclophosphamide toxicity. Modified Rodnan skin score and forced vital capacity improved with time (p< 0.001). By multivariate analysis, baseline skin score >24 and older age at transplant were associated with lower progression free survival (Hazard ration 3.32) and 1.77, respectively). CD34+-selection was associated with better response (Hazard ration: 0.46). This study confirms the efficacy of autologous stem cell transplantation in real-life practice for severe systemic sclerosis using non myeloablative conditioning. Careful cardio-pulmonary assessment to identify organ involvement at patient referral, reduced cyclophosphamide doses and CD34+ selection may improve outcomes. The study was registered at ClinicalTrials.gov: NCT02516124.

Treatment of patients with MYC rearrangement positive large B-cell lymphoma with R-CHOP plus lenalidomide: results of a multicenter HOVON phase II trial.

Patients with MYC-rearrangement positive large B-cell lymphoma (MYC+ LBCL) have an inferior prognosis following standard first-line therapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) as compared to patients without MYC rearrangement. Although intensive chemotherapy regimens yield higher remission rates, toxicity remains a concern. Lenalidomide is an oral immunomodulatory drug which downregulates MYC and its target genes thereby providing support using lenalidomide as additional therapeutic option for MYC+ LBCL. A phase II trial was conducted evaluating the efficacy of lenalidomide (15 mg day 1-14) in combination with R-CHOP (R2CHOP) in newly diagnosed MYC+ LBCL patients identified through a nationwide MYC-FISH screening program. The primary endpoint was complete metabolic response (CMR) on centrally reviewed 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)-computer tomography (CT)-scan at end-of-treatment. Secondary endpoints were overall survival (OS), disease-free survival (DFS) and event-free survival (EFS). Eighty-two patients with stage II-IV MYC+ LBCL were treated with 6 cycles of R2CHOP. At EOT, 67% (confidence interval (CI) 58-75%) of the patients reached CMR. With a median follow-up of 25.4 months, 2-year estimates (95% CI) for OS, DFS, EFS were 73% (62-82%), 75% (63-84%) and 63% (52-73%) respectively. In this prospective trial for newly diagnosed MYC+ LBCL patients, we found that administering R2CHOP was safe, and yields comparable CMR and survival rates as in studies applying more intensive chemotherapy regimens. Hence, these findings offer new prospects for MYC+ LBCL patients and warrant comparison in prospective randomized clinical trials. This trial was registered at www.clinicaltrialsregister.eu (#2014-002654-39).

Proteomic markers with prognostic impact on outcome of chronic lymphocytic leukemia patients under chemo-immunotherapy: results from the HOVON 109 study.

Despite recent identification of several prognostic markers, there is still a need for new prognostic parameters able to predict clinical outcome in chronic lymphocytic leukemia (CLL) patients. Here, we aimed to validate the prognostic ability of known (proteomic) markers measured pretreatment and to search for new proteomic markers that might be related to treatment response in CLL. To this end, baseline serum samples of 51 CLL patients treated with chemo-immunotherapy were analyzed for 360 proteomic markers, using Olink technology. Median event-free survival (EFS) was 23 months (range: 1.25-60.9). Patients with high levels of sCD23 (>11.27, p = 0.026), sCD27 (>11.03, p = 0.04), SPINT1 (>1.6, p = 0.001), and LY9 (>8.22, p = 0.0003) had a shorter EFS than those with marker levels below the median. The effect of sCD23 on EFS differed between immunoglobulin heavy chain variable gene-mutated and unmutated patients, with the shortest EFS for unmutated CLL patients with sCD23 levels above the median. Taken together, our results validate the prognostic impact of sCD23 and highlight SPINT1 and LY9 as possible promising markers for treatment response in CLL patients.

Predictive factors for treatment-related mortality and major adverse events after autologous haematopoietic stem cell transplantation for systemic sclerosis: results of a long-term follow-up multicentre study.

BACKGROUND: Autologous haematopoietic stem cell transplantation (HSCT) improves survival in systemic sclerosis (SSc) with poor prognosis, but is hampered by treatment-related mortality (TRM). OBJECTIVE: To evaluate event-free survival (EFS), TRM, response to treatment, disease progression and patient characteristics associated with events. METHODS: All patients treated with HSCT for SSc in The Netherlands until 2017 (n=92) were included. Data on skin involvement (modified Rodnan skin score (mRSS), pulmonary function (forced vital capacity (FVC) and diffusion capacity of the lungs for carbon monoxide (DLCO)), extent of interstitial lung disease on high-resolution CT using Goh scores and left ventricular ejection fraction (LVEF) were collected at baseline, 1, 2 and 5 years. Occurrence of events, defined as death or major organ failure, were collected until 2019. As control, a comparison between patients treated with cyclophosphamide (CYC) and patients with HSCT who participated in the Autologous Stem Cell Transplantation International Scleroderma (ASTIS) trial was performed. RESULTS: Median follow-up was 4.6 years. EFS estimates at 5, 10 and 15 years were 78%, 76% and 66%, respectively. Twenty deaths occurred. Mean FVC, DLCO, mRSS and Goh scores all improved significantly. Disease progression occurred in 22 patients. Frequency of TRM decreased over time and occurred more often in males. Events were independently associated with male sex, LVEF <50% and older age. In ASTIS, patients treated with HSCT (n=23) 7 events occurred versus 13 in the CYC group (n=22). CONCLUSION: Our data confirm long-term efficacy of HSCT in improving survival, skin and lung involvement in SSc. Male sex, lower LVEF and older age at baseline were identified as risk factors for events.

Feasibility and efficacy of addition of individualized-dose lenalidomide to chlorambucil and rituximab as first-line treatment in elderly and FCR-unfit patients with advanced chronic lymphocytic leukemia.

Lenalidomide has been proven to be effective but with a distinct and difficult to manage toxicity profile in the context of chronic lymphocytic leukemia, potentially hampering combination treatment with this drug. We conducted a phase 1-2 study to evaluate the efficacy and safety of six cycles of chlorambucil (7 mg/m2 daily), rituximab (375 mg/m2 cycle 1 and 500 mg/m2 cycles 2-6) and individually-dosed lenalidomide (escalated from 2.5 mg to 10 mg) (induction-I) in first-line treatment of patients with chronic lymphocytic leukemia unfit for treatment with fludarabine, cyclophosphamide and rituximab. This was followed by 6 months of 10 mg lenalidomide monotherapy (induction-II). Of 53 evaluable patients in phase 2 of the study, 47 (89%) completed induction-I and 36 (68%) completed induction-II. In an intention-to-treat analysis, the overall response rate was 83%. The median progression-free survival was 49 months, after a median follow-up time of 27 months. The 2- and 3-year progression-free survival rates were 58% and 54%, respectively. The corresponding rates for overall survival were 98% and 95%. No tumor lysis syndrome was observed, while tumor flair reaction occurred in five patients (9%, 1 grade 3). The most common hematologic toxicity was grade 3-4 neutropenia, which occurred in 73% of the patients. In conclusion, addition of lenalidomide to a chemotherapy backbone followed by a fixed duration of lenalidomide monotherapy resulted in high remission rates and progression-free survival rates, which seem comparable to those observed with novel drug combinations including novel CD20 monoclonal antibodies or kinase inhibitors. Although lenalidomide-specific toxicity remains a concern, an individualized dose-escalation schedule is feasible and results in an acceptable toxicity profile. EuraCT number: 2010-022294-34.

Immune surveillance by autoreactive CD4-positive helper T cells is a common phenomenon in patients with acute myeloid leukemia.

OBJECTIVES: The importance of autologous T-cell responses in immune surveillance against acute myeloid leukemia (AML) remains unclear. Therefore, we investigated the presence and functional reactivity of autoreactive T-cell responses against autologous AML blasts. METHODS: T cells purified from PB samples harvested from patients during first complete remission were stimulated with autologous AML material harvested at diagnosis. After 12-14 days of coculture, the T cells were restimulated with autologous AML cells, and leukemia-reactive T-cell clones were isolated based on their expression of the activation marker CD137. RESULTS: We demonstrated that AML-induced autoreactivity was predominantly mediated by CD4 T cells. These autoreactive T cells showed abundant cytokine production, coincided by modest cytotoxic activity. Upon coculture, the autoreactive T cells were able to increase the immunogenicity of the AML blasts. Interestingly, similar AML-directed reactivity was observed using HLA-identical responder T cells from healthy donors. CONCLUSIONS: We demonstrated that the presence of AML-directed autoreactive T cells is a common phenomenon which appears to be part of the general T-cell repertoire also in healthy individuals. This autoreactive AML-directed T-cell response may directly contribute to anti-AML immune surveillance especially in the situation of minimal residual disease, but furthermore the immune-modulatory effect on the AML phenotype may pave the way for other immunological interventions.

Control of Cytomegalovirus Viremia after Allogeneic Stem Cell Transplantation: A Review on CMV-Specific T Cell Reconstitution.

Recipients of allogeneic stem cell transplantation (alloSCT) are at risk for reactivation of endogenous herpesviruses due to profound and prolonged T cell deficiency following conditions such as graft-versus-host disease, immunosuppression, and/or T cell depletion. Reactivation of endogenous cytomegalovirus (CMV) is the most frequently occurring herpesvirus reactivation following alloSCT. Antiviral medication is often used in pre-emptive treatment strategies initiated when increases in CMV viral loads are detected as a result of active reactivation of the virus. Despite pre-emptive antiviral treatment, the incidence of CMV disease in CMV-seropositive alloSCT patients is still 10% at 1 year following alloSCT. This illustrates the necessity for adequate CMV-specific T cell immunity for long-term control of CMV and prevention of CMV disease. In this review, we analyzed the available studies on the influence of donor CMV status on CMV-specific T cell reconstitution and CMV disease. Furthermore, we reviewed the available studies on the safety and efficacy of adoptive transfer of donor CMV-specific T cells for the prevention and treatment of CMV disease following alloSCT, including studies on adoptive transfer of third-party CMV-specific T cells as a possible alternative when donor T cells are not available.

Randomized controlled trial on the effects of a supervised high intensity exercise program in patients with a hematologic malignancy treated with autologous stem cell transplantation: Results from the EXIST study.

BACKGROUND: This single blind, multicenter randomized controlled trial aimed to evaluate the effectiveness of a supervised high intensity exercise program on physical fitness and fatigue in patients with multiple myeloma or lymphoma recently treated with autologous stem cell transplantation. METHODS: 109 patients were randomly assigned to the 18-week exercise intervention or the usual care control group. The primary outcomes included physical fitness (VO2peak and Wpeak determined using a cardiopulmonary exercise test; grip strength and the 30s chair stand test) and fatigue (Multidimensional Fatigue Inventory) and were assessed prior to randomization and after completion of the intervention or at similar time points for the control group. Multivariable multilevel linear regression analyses were performed to assess intervention effects. RESULTS: Patients in the intervention group attended 86% of the prescribed exercise sessions. Of the patients in the control group, 47% reported ≥10 physiotherapy sessions, which most likely included supervised exercise, suggesting a high rate of contamination. Median improvements in physical fitness ranged between 16 and 25% in the intervention group and between 12 and 19% in the control group. Fatigue decreased in both groups. There were no significant differences between the intervention and control group. CONCLUSION: We found no significant beneficial effects of the supervised high intensity exercise program on physical fitness and fatigue when compared to usual care. We hypothesized that the lack of significant intervention effects may relate to suboptimal timing of intervention delivery, contamination in the control group and/or suboptimal compliance to the prescribed exercise intervention. TRIAL REGISTRATION: Netherlands Trial Register-NTR2341.

Integrated Whole Genome and Transcriptome Analysis Identified a Therapeutic Minor Histocompatibility Antigen in a Splice Variant of ITGB2.

PURPOSE: In HLA-matched allogeneic hematopoietic stem cell transplantation (alloSCT), donor T cells recognizing minor histocompatibility antigens (MiHAs) can mediate desired antitumor immunity as well as undesired side effects. MiHAs with hematopoiesis-restricted expression are relevant targets to augment antitumor immunity after alloSCT without side effects. To identify therapeutic MiHAs, we analyzed the in vivo immune response in a patient with strong antitumor immunity after alloSCT. EXPERIMENTAL DESIGN: T-cell clones recognizing patient, but not donor, hematopoietic cells were selected for MiHA discovery by whole genome association scanning. RNA-sequence data from the GEUVADIS project were analyzed to investigate alternative transcripts, and expression patterns were determined by microarray analysis and qPCR. T-cell reactivity was measured by cytokine release and cytotoxicity. RESULTS: T-cell clones were isolated for two HLA-B*15:01-restricted MiHA. LB-GLE1-1V is encoded by a nonsynonymous SNP in exon 6 of GLE1 For the other MiHAs, an associating SNP in intron 3 of ITGB2 was found, but no SNP disparity was present in the normal gene transcript between patient and donor. RNA-sequence analysis identified an alternative ITGB2 transcript containing part of intron 3. qPCR demonstrated that this transcript is restricted to hematopoietic cells and SNP-positive individuals. In silico translation revealed LB-ITGB2-1 as HLA-B*15:01-binding peptide, which was validated as hematopoietic MiHA by T-cell experiments. CONCLUSIONS: Whole genome and transcriptome analysis identified LB-ITGB2-1 as MiHAs encoded by an alternative transcript. Our data support the therapeutic relevance of LB-ITGB2-1 and illustrate the value of RNA-sequence analysis for discovery of immune targets encoded by alternative transcripts. Clin Cancer Res; 22(16); 4185-96. ©2016 AACR.

Multi-state analysis illustrates treatment success after stem cell transplantation for acute myeloid leukemia followed by donor lymphocyte infusion.

In the field of hematopoietic stem cell transplantation, the common approach is to focus outcome analyses on time to relapse and death, without assessing the impact of post-transplant interventions. We investigated whether a multi-state model would give insight into the events after transplantation in a cohort of patients who were transplanted using a strategy including scheduled donor lymphocyte infusions. Seventy-eight consecutive patients who underwent myeloablative T-cell depleted allogeneic stem cell transplantation for acute myeloid leukemia or myelodysplastic syndrome were studied. We constructed a multi-state model to analyze the impact of donor lymphocyte infusion and graft-versus-host disease on the probabilities of relapse and non-relapse mortality over time. Based on this model we introduced a new measure for outcome after transplantation which we called 'treatment success': being alive without relapse and immunosuppression for graft-versus-host disease. All relevant clinical events were implemented into the multi-state model and were denoted treatment success or failure (either transient or permanent). Both relapse and non-relapse mortality were causes of failure of comparable magnitude. Whereas relapse was the dominant cause of failure from the transplantation state, its rate was reduced after graft-versus-host disease, and especially after donor lymphocyte infusion. The long-term probability of treatment success was approximately 40%. This probability was increased after donor lymphocyte infusion. Our multi-state model helps to interpret the impact of post-transplantation interventions and clinical events on failure and treatment success, thus extracting more information from observational data.

Fifteen years of external quality assessment in leukemia/lymphoma immunophenotyping in The Netherlands and Belgium: A way forward.

In 1985, external quality assurance was initiated in the Netherlands to reduce the between-laboratory variability of leukemia/lymphoma immunophenotyping and to improve diagnostic conclusions. This program consisted of regular distributions of test samples followed by biannual plenary participant meetings in which results were presented and discussed. A scoring system was developed in which the quality of results was rated by systematically reviewing the pre-analytical, analytical, and post-analytical assay stages using three scores, i.e., correct (A), minor fault (B), and major fault (C). Here, we report on 90 consecutive samples distributed to 40-61 participating laboratories between 1998 and 2012. Most samples contained >20% aberrant cells, mainly selected from mature lymphoid malignancies (B or T cell) and acute leukemias (myeloid or lymphoblastic). In 2002, minimally required monoclonal antibody (mAb) panels were introduced, whilst methodological guidelines for all three assay stages were implemented. Retrospectively, we divided the study into subsequent periods of 4 ("initial"), 4 ("learning"), and 7 years ("consolidation") to detect "learning effects." Uni- and multivariate models showed that analytical performance declined since 2002, but that post-analytical performance improved during the entire period. These results emphasized the need to improve technical aspects of the assay, and reflected improved interpretational skills of the participants. A strong effect of participant affiliation in all three assay stages was observed: laboratories in academic and large peripheral hospitals performed significantly better than those in small hospitals. © 2015 International Clinical Cytometry Society.

Endosonography for the diagnosis of malignant lymphoma presenting with mediastinal lymphadenopathy.

BACKGROUND: Endosonography combined with fine needle aspiration (FNA) is a minimally invasive technique for intrathoracic mediastinal nodal sampling. The value of endosonography with FNA for the diagnosis of malignant mediastinal lymphoma is under debate. In this study, the sensitivity and negative predictive value of endosonography for the assessment of primary versus recurrent malignant lymphoma were assessed. METHODS: Forty-nine patients with suspected primary (n=32) or recurrent (n=17) lymphoma were retrospectively analyzed. They presented with mediastinal nodal enlargement and underwent endosonography for diagnostic purposes between 2001 and 2011. The final diagnosis was based on surgical biopsy, conclusive cell block analysis, or longstanding clinical and radiologic follow-up. RESULTS: In 33 patients, a final diagnosis of lymphoma was established; in 16 patients (33%) alternative diagnoses (eg, small cell lung cancer, sarcoidosis) were found. Sensitivity and negative predictive value of endosonography in diagnosing primary versus recurrent mediastinal lymphoma were 55% and 57% versus 88% and 90%, respectively. No complications occurred during these procedures. CONCLUSIONS: On the basis of these data, we conclude that endosonography is a minimally invasive, safe, and sensitive method for the assessment of recurrent mediastinal malignant lymphoma or alternative diagnoses but has limitations in assessing a primary lymphoma diagnosis.

Rapid induction of single donor chimerism after double umbilical cord blood transplantation preceded by reduced intensity conditioning: results of the HOVON 106 phase II study.

Double umbilical cord blood transplantation is increasingly applied in the treatment of adult patients with high-risk hematological malignancies and has been associated with improved engraftment as compared to that provided by single unit cord blood transplantation. The mechanism of improved engraftment is, however, still incompletely understood as only one unit survives. In this multicenter phase II study we evaluated engraftment, early chimerism, recovery of different cell lineages and transplant outcome in 53 patients who underwent double cord blood transplantation preceded by a reduced intensity conditioning regimen. Primary graft failure occurred in one patient. Engraftment was observed in 92% of patients with a median time to neutrophil recovery of 36 days (range, 15-102). Ultimate single donor chimerism was established in 94% of patients. Unit predominance occurred by day 11 after transplantation and early CD4(+) T-cell chimerism predicted for unit survival. Total nucleated cell viability was also associated with unit survival. With a median follow up of 35 months (range, 10-51), the cumulative incidence of relapse and non-relapse mortality rate at 2 years were 39% and 19%, respectively. Progressionfree survival and overall survival rates at 2 years were 42% (95% confidence interval, 28-56) and 57% (95% confidence interval, 43-70), respectively. Double umbilical cord blood transplantation preceded by a reduced intensity conditioning regimen using cyclophosphamide/fludarabine/4 Gy total body irradiation results in a high engraftment rate with low non-relapse mortality. Moreover, prediction of unit survival by early CD4(+) lymphocyte chimerism might suggest a role for CD4(+) lymphocyte mediated unit-versus-unit alloreactivity. www.trialregister.nl NTR1573.

Clinical and biological impact of TET2 mutations and expression in younger adult AML patients treated within the EORTC/GIMEMA AML-12 clinical trial.

We assessed the prognostic impact of TET2 mutations and mRNA expression in a prospective cohort of 357 adult AML patients < 60 years of age enrolled in the European Organization For Research and Treatment of Cancer (EORTC)/Gruppo Italiano Malattie Ematologiche dell' Adulto (GIMEMA) AML-12 06991 clinical trial. In addition the co-occurrence with other genetic defects and the functional consequences of TET2 mutations were investigated. TET2 mutations occurred in 7.6 % of the patients and were an independent marker of poor prognosis (p = 0.024). TET2 and IDH1/2 mutations strongly associated with aberrations in the DNA methyltransferase DNMT3A. Functional studies confirmed previous work that neither nonsense truncations, nor missense TET2 mutations, induced 5-hydroxymethylcytosine formation. In addition, we now show that mutant TET2 forms did not act in a dominant negative manner when co-expressed with the wild-type protein. Finally, as loss-of-function TET2 mutations predicted poor outcome, we questioned whether low TET2 mRNA expression in cases of AML without TET2 mutations would affect overall survival. Notably, also AML patients with low TET2 mRNA expression levels showed inferior overall survival.

Autologous hematopoietic stem cell transplantation vs intravenous pulse cyclophosphamide in diffuse cutaneous systemic sclerosis: a randomized clinical trial.

IMPORTANCE: High-dose immunosuppressive therapy and autologous hematopoietic stem cell transplantation (HSCT) have shown efficacy in systemic sclerosis in phase 1 and small phase 2 trials. OBJECTIVE: To compare efficacy and safety of HSCT vs 12 successive monthly intravenous pulses of cyclophosphamide. DESIGN, SETTING, AND PARTICIPANTS: The Autologous Stem Cell Transplantation International Scleroderma (ASTIS) trial, a phase 3, multicenter, randomized (1:1), open-label, parallel-group, clinical trial conducted in 10 countries at 29 centers with access to a European Group for Blood and Marrow Transplantation-registered transplant facility. From March 2001 to October 2009, 156 patients with early diffuse cutaneous systemic sclerosis were recruited and followed up until October 31, 2013. INTERVENTIONS: HSCT vs intravenous pulse cyclophosphamide. MAIN OUTCOMES AND MEASURES: The primary end point was event-free survival, defined as time from randomization until the occurrence of death or persistent major organ failure. RESULTS: A total of 156 patients were randomly assigned to receive HSCT (n = 79) or cyclophosphamide (n = 77). During a median follow-up of 5.8 years, 53 events occurred: 22 in the HSCT group (19 deaths and 3 irreversible organ failures) and 31 in the control group (23 deaths and 8 irreversible organ failures). During the first year, there were more events in the HSCT group (13 events [16.5%], including 8 treatment-related deaths) than in the control group (8 events [10.4%], with no treatment-related deaths). At 2 years, 14 events (17.7%) had occurred cumulatively in the HSCT group vs 14 events (18.2%) in the control group; at 4 years, 15 events (19%) had occurred cumulatively in the HSCT group vs 20 events (26%) in the control group. Time-varying hazard ratios (modeled with treatment × time interaction) for event-free survival were 0.35 (95% CI, 0.16-0.74) at 2 years and 0.34 (95% CI, 0.16-0.74) at 4 years. CONCLUSIONS AND RELEVANCE: Among patients with early diffuse cutaneous systemic sclerosis, HSCT was associated with increased treatment-related mortality in the first year after treatment. However, HCST conferred a significant long-term event-free survival benefit. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN54371254.