Adult B-cell precursor acute lymphoblastic leukemia (BCP-ALL) with t(4;11)(q21;q23);KMT2A/AFF1 is a poor-prognosis entity. This registry-based study was aimed to analyze outcome of patients with t(4;11) BCP-ALL treated with allogeneic hematopoietic stem cell transplantation (alloHSCT) in first complete remission (CR1) between 2000 and 2017, focusing on the impact of measurable residual disease (MRD) at the time of transplant. Among 151 patients (median age, 38) allotransplanted from either HLA-matched siblings or unrelated donors, leukemia-free survival (LFS) and overall survival (OS) at 2 years were 51% and 60%, whereas relapse incidence (RI) and non-relapse mortality (NRM) were 30% and 20%, respectively. These results were comparable to a cohort of contemporary patients with diploid normal karyotype (NK) BCP-ALL with equivalent inclusion criteria (n = 567). Among patients with evaluable MRD pre-alloHSCT, a negative status was the strongest beneficial factor influencing LFS (hazard ratio [HR] = 0.2, p < 0.001), OS (HR = 0.14, p < 0.001), RI (HR = 0.23, p = 0.001), and NRM (HR = 0.16, p = 0.002), with a similar outcome to MRD-negative NK BCP-ALL patients. In contrast, among patients with detectable pretransplant MRD, outcome in t(4;11) BCP-ALL was inferior to NK BCP-ALL (LFS: 27% vs. 50%, p = 0.02). These results support indication of alloHSCT in CR1 for t(4;11) BCP-ALL patients, provided a negative MRD status is achieved. Conversely, pre-alloHSCT additional therapy is warranted in MRD-positive patients.

Donor cell leukaemia (DCL) is a rare complication of allogeneic haematopoietic cell transplantation (HCT). We have investigated the prevalence and outcome of donor cell haematology malignancies within centres registered with the European Society of Blood and Marrow transplantation (EBMT). We have sought to identify risk factors to shed light on the pathogenesis of DCL as a model for leukaemogenesis. DCL cases were identified by questionnaire and a follow-up questionnaire requested detailed data. Control subjects from the EBMT registry who had not developed DCL were used for a matched pair analysis to identify risk factors. We identified 38 patients with DCL; the estimated prevalence was 80.5/100,000 transplants. Patients were predominantly treated for haematological malignancy. A clone was retrospectively identified in 7/25 (28%) donors for whom data was available. Overall survival was poor with 29/38 patients dead a median of 11 (range 0-91) months after DCL diagnosis. Matched case-pair analysis identified three factors on multivariate analysis as significantly associated with an increased risk for DCL: use of growth factors within the first 100 days after transplantation, in vivo T-cell depletion and multiple allografts. The risk factors identified, support reduced immune surveillance and replicative stress as pathogenic in the development of DCL.

In the context of discussions on the reproducibility of clinical studies, we reanalyzed a prospective randomized study on the role of splenic irradiation as adjunct to the conditioning for hematopoietic stem cell transplantation (HSCT) for chronic myeloid leukemia (CML). Between 1986 and 1989, a total of 229 patients with CML were randomized; of these, 225 (98 %; 112 with, 113 without splenic irradiation) could be identified in the database and their survival updated. Results confirmed the early findings with no significant differences in all measured endpoints (overall survival at 25 years: 42.7 %, 32.0–52.4 % vs 52.9 %, 43.2–62.6 %; p = 0.355, log rank test). Additional splenic irradiation failed to reduce relapse incidence. It did not increase non-relapse mortality nor the risk of late secondary malignancies. Comforting are the long-term results from this predefined consecutive cohort of patients: more than 60 % were alive at plus 25 years when they were transplanted with a low European Society for Blood and Marrow Transplantation (EBMT) risk sore. This needs to be considered today when treatment options are discussed for patients who failed initial tyrosine kinase inhibitor therapy and have an available low risk HLA-identical donor.

We have recently reported on the outcome of autologous transplantation in the rare myelomas (IgD, IgE, IgM, and nonsecretory [NS]) but there is no real information on the outcome of these conditions after allogeneic transplantation. We used the European Group for Blood and Marrow Transplantation myeloma database to compare the outcomes after allogeneic transplantation of 1354 common myelomas (IgG, IgA, and light chain myeloma) with the outcome in 26 IgD myelomas and 52 NS myelomas. There was little difference between common and the IgD and NS myeloma patients with respect to prognostic factors although the IgD group had a higher beta 2 microglobulin at diagnosis, shorter time to transplantation, and more T cell depletion. IgD and NS patients had a significantly greater achievement of complete remission at conditioning but this did not translate into equivalent progression-free survival and overall survival for the IgD patients although the NS outcome was very similar to that of common myeloma. The PFS and OS of IgD, common, and NS myelomas appear similar after allogeneic transplantation, despite a tendency for higher early relapse rate in IgD myeloma. Allogeneic transplantation may, therefore, be an option to investigate in prospective observational studies.

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.

Despite the revolutionary change in the prognosis of chronic myeloid leukemia (CML) patients with the introduction of imatinib, patients with resistant disease still pose a considerable problem. In this multicenter, randomized phase III trial, we investigate whether the combination of high-dose imatinib and intermediate-dose cytarabine compared to high-dose imatinib alone, improves the rate of major molecular response (MMR) in newly diagnosed CML patients. This study was closed prematurely because of declining inclusion due to the introduction of second generation tyrosine kinase inhibitors and only one third of the initially required patients were accrued. One hundred nine patients aged 18–65 years were randomly assigned to either imatinib 800 mg (n = 55) or to imatinib 800 mg in combination with two successive cycles of cytarabine 200 mg/m2 for 7 days (n = 54). After a median follow-up of 41 months, 67 % of patients were still on protocol treatment. The MMR rate at 12 months was 56 % in the imatinib arm and 48 % in the combination arm (p = 0.39). Progression-free survival was 96 % after 1 year and 89 % after 4 years. Four-year overall survival was 97 %. Adverse events grades 3 and 4 were more common in the combination arm. The addition of intermediate-dose of cytarabine to imatinib did not improve the MMR rate at 12 months. However, the underpowering of the study precludes any definitive conclusions. This trial is registered at www.trialregister.nl (NTR674).

Abstract 3014FN2 This icon denotes a clinically relevant abstract

Abstract Abstract 2758 Background Imatinib (IM) is considered the first line therapy for newly diagnosed chronic myeloid leukemia (CML). Despite the increased overall survival and event free survival attained with IM, patients with unsatisfactory responses due to IM resistance still pose a considerable challenge. Addition of cytarabine to IM has shown synergistic anti-proliferative effects in in-vitro studies as well as in clinical trials. We conducted a prospective, multicenter, phase III trial (HOVON 78) comparing high dose IM or high dose IM combined with 2 successive cycles of standard-dose cytarabine in newly diagnosed CML patients. At the time our study was set out, high dose IM (600 or 800 mg) showed significantly higher molecular response rates than 400 mg in a HOVON dose escalation study (HOVON 51) of the combination of IM and cytarabine. Patients and methods This study started in June 2006, but was closed prematurely in April 2010 because of declining inclusion most probably due to excellent evolving results of IM monotherapy and the introduction of second generation tyrosine kinase inhibitors. Newly diagnosed CML patients between the age of 18 and 65 years in first chronic phase ≤ 2 months were randomized between IM monotherapy 800 mg daily (arm A) or IM 800 mg combined with 2 successive cycles of daily cytarabine 200 mg/m2 in 1–2 hours infusion for 7 days (arm B), followed by IM monotherapy. The first cycle of cytarabine was given as soon as possible, preferably within 14–28 days from the start of IM, whereas the second cycle was started after hematopoietic recovery (i.e. platelets > 100×109/l and WBC > 2.0×109/l). Response to treatment was assessed by hematological, cytogenetic and molecular analyses at regular intervals and was scored according to the ELN criteria. Reasons for going off protocol treatment were progression, excessive toxicity or intolerance of treatment, intercurrent death, no compliance of the patient or major protocol violation. The primary endpoint was the achievement of a major molecular response (MMR) at 12 months, and was compared between the 2 treatment arms using logistic regression. Secondary endpoints were progression free survival, overall survival and toxicity. The analyses were done according to the intention to treat principle, and were based on data available as of August 8, 2011. In order to detect with 80% power an improvement in 12-months' MMR from 60% to 75% (2-sided significance level alpha=0.05), 330 patients were required. Results One hundred and ten eligible patients from 19 Dutch and 2 Belgian centers were enrolled, 55 in each arm. One patient in arm B withdrew consent. The median age of the patients was 45 years (range, 17–65). Sokal risk scores were equally divided between the two groups, but arm A contained more patients with high Euro risk score (24 vs 7%, p = 0.03). Median follow up is 31 months (range, 0–57). So far, 34 patients went off protocol treatment; 16 in arm A and 18 in arm B. Reasons for going off protocol were progression to accelerated phase, blast crisis or progression from major molecular response (3 and 1 patients in arm A and arm B, respectively), excessive toxicity (7 vs 11), and other (6 vs 6). Nine patients in arm B only received one cycle of cytarabine. Cytarabine dose was reduced in one patient only in the first cycle. Although the molecular response data of 4 patients are not yet available, the proportion of patients who achieved a MMR at 12 months was similar between the two treatment arms; 51% in arm A and 47% in arm B (OR = 0.82, 95% CI 0.38–1.76, p = 0.60; adjusted for Sokal score), PFS at 48 months was 91% in both treatment arms (p = 0.80). OS at 48 months was 100% in arm A and 92% in arm B. Three patients died. One patient in arm A died of conduction abnormality, 49 months after start of therapy. This patient had switched to dasatinib treatment because of IM resistance. Two patients in arm B died, both having progressed to blast crisis. One died at 39 months due to aspergillus infection after allogenic stem cell transplantation, and one patient on dasatinib treatment died at 9 months due to an intracerebral bleeding. Forty SAEs occurred in 29 patients, 7 (in 6 patients) in arm A and 33 (23 patients) in arm B (p<0.001). The most common toxicities were pain, constitutional symptoms and gastro-intestinal complaints. Conclusion IM in combination with cytarabine is not superior compared to IM alone in achieving MMR at 12 months. Patients receiving combination therapy had significantly more toxicity. Disclosures: Janssen: Novartis: Consultancy. Ossenkoppele:Novartis: Consultancy.

Abstract Abstract 688 Prognosis of Mantle cell lymphoma (MCL) has recently improved by the use of combination of monoclonal anti-CD20 immunotherapy, high-dose cytarabine containing regimen and autologous stem cell transplantation (ASCT). During the last decade the use of TBI, as part of the conditioning regimen of ASCT, has drastically decreased. This attitude is questionable since first, MCL cell lines exhibit a high sensitivity to radiotherapy in vitro and second, a retrospective study including 18 patients suggested that TBI may improve the EFS after ASCT in MCL (Milpied et al, BMT 1998). Aim. We performed a large retrospective study from the EBMT registry to assess the role of TBI in the conditioning regimen of ASCT in MCL. Patients and methods. All patients who underwent an ASCT between 2000 and 2007 in complete or first partial remission (CR/PR1) registered within the EBMT data-base with complete MedB forms available were eligible for this study. Results. Altogether 418 patients met the eligibility criteria. Median age was 51 years (range 29 to 65 years). At diagnosis 93% of the patients presented with a stage III/IV disease. Most of the patients (85%) had received one line of chemotherapy prior to ASCT. According to reported treatments, 122 patients (31%) had received Rituximab (R) and high-dose cytarabine (HD-Cyt) before transplantation and 111 patients (29%) had not received any of these drugs. At transplant, 283 patients (68%) were in CR and 135 (32%) in PR1. Conditioning regimen for ASCT contained TBI in 152 patients (36.5%) and consisted on a BEAM-based chemotherapy in 92% of the 266 patients transplanted with a non-TBI regimen. Stem cell source was peripheral blood for 99.3% of patients. With a median follow-up of 29 months, median overall and disease free survival (OS and DFS) of all patients were 99 and 57 months, respectively. Disease status at transplant appeared as a significant predictive factor for DFS and relapse incidence (RI) but at the time of analysis had no impact on OS. In comparison to patients transplanted in CR, those transplanted in PR1 had an impaired DFS (median DFS 52 months versus 40 months, respectively) (RR= 1,53, 95% CI 1.10–2.14, p=0.01) with an increased incidence of relapse (RR= 1.49, 95% CI 1.04–2.13, p= 0.03). Since we found a significant interaction between the use of TBI and disease status on the incidence of relapse, all further analysis were stratified on disease status at transplant. The use of R and HD-Cyt before ASCT or TBI in the conditioning of ASCT did not have any impact on OS, DFS and RI of patients transplanted in CR. In contrast, for patients transplanted in PR1, pre-transplant treatment with R and HD-Cyt was associated with a prolonged DFS in comparison to those who did not receive these treatments (median DFS 52 months versus 27 months, respectively, p=0.0891). Moreover, in patients in PR1 at transplant, the use of TBI was associated with a significant reduction of the incidence of relapse in both univariate and multivariate analysis (p=0.034 and RR= 0.409, 95% CI 0.213–0.786, p=0.007, respectively). There was a trend to a better DFS in patients transplanted in PR1 with TBI (median DFS 60 months with TBI versus 33 months without TBI, p=0.123). At the time of analysis, overall survival and non relapse mortality (NRM) were similar between patients who received TBI and those who did not. Three secondary malignancies were reported in this series of patients with two occurring in the TBI group Conclusion. In this retrospective series of autografted MCL, the risk of relapse after ASCT is mainly dependant on the disease status at transplant. TBI or other radiotherapy-based conditioning can be probably avoided in patients transplanted in CR but should still be considered in patients who can not achieve a better response than PR at transplant. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 363 Matched unrelated donor stem cell transplantation (MUD-SCT) has recently become a therapeutic option for patients with B cell diffuse large cell lymphoma (DLBCL) who fail other conventional therapies and do not have a matched sibling donor available. We present retrospective data of 473 DLBCL patients, 285 males and 188 females, aged 18 to 69 years (median 46 years), treated with matched sibling (n=301) or matched unrelated (n=172) SCT between January 2000 and December 2007 and reported to the EBMT registry. Median time from diagnosis to allograft was 25 months (range 2 – 203). Fifty-seven percent of the patients had failed previous autologous SCT, and 12% were transplanted in chemorefractory disease. After a median follow up of 41 months, the estimated 3-year non-relapse mortality (NRM), relapse rate (RR), progression free survival (PFS) and overall survival (OS) for the whole series were 37%, 32%, 31% and 40%, respectively. There were no statistically significant differences in patient age, disease status at transplantation, stem cell source and intensity of conditioning regimen between the Sib and the MUD cohorts (summarized in Table 1).However, a higher number of patients undergoing MUD have already failed an autograft (66% vs 52%, p=0.004), and T cell depleted grafts were more frequently used in the MUD cohort. Acute GvHD occurred in 48% of patients treated with a sib allograft vs 54% in those receiving a MUD (p=n.s). Interestingly, there were no statistically significant differences in NRM and RR between the Sib and the MUD groups (3 yr NRM=38% vs 37%, RR approached 38% vs 34%), resulting in a similar 3-year PFS and OS (32% vs 29% and 42% vs 35%, respectively). Multivariate analysis identified refractory disease (p = 0.001, RR 3.2; CI=1.3-3.5), poor performance status (p = 0.017, RR 1.9; CI=1.1-3.4) and age at transplantation > 50 years (p = 0.015, RR1.5; CI=1.1-2.1) as independent adverse prognostic factors for NRM and time from diagnosis to SCT < 36 months (p = 0.02, RR 1.5; CI=1.1-2.1), a previously failed autologous SCT (p = 0.026, RR .4; CI=1.1-1.9), refractory disease (p = 0.003, RR 2; CI=1.3-3.1), poor performance status (p = 0.0001, RR 3.5; CI=2.1-5.6) and T cell depletion (p = 0.001, RR 2; CI=1.3-2.9) as adverse prognostic factors for RR. A previous autologous SCT, poor performance status and refractory disease at transplantation were found to be significantly associated with a shorter PFS (p=0.04, RR 1.3; CI=1-1.6; p=0.0001, RR 2.4; CI=1.6-3.4; p=0.000,RR 2.1; CI=1.5-2.9, respectively) and refractory disease (p=0.0001, RR 2.2; CI=1.6-3.1) and poor performance status at the time of SCT (p=0.0001, RR 2.5; CI=1.7-3.6) with a shorter OS. Patients allografted from MUD tended to have a slightly increased risk of overall mortality in multivariate analysis, but this was not statistically significant (p=0.06, RR 1.2; CI=0.95-1.6). In conclusion, MUD SCT provides a curative option, not significantly inferior to that obtained with a matched sibling transplant, for selected patients with DLBCL who have failed conventional therapies, including autograft. Similarly, the type of conditioning regimen was not found to have a significant impact on patient outcome. Table 1. Clinical characteristics Sib vs MUD Sib (n = 301) MUD (n= 172) p Age (median, years) 46 45 N.S. Previous ASCT 48% 33% 0.004 Refractory disease 12% 12% N.S. Poor P.S. 13% 7% 0.06 RIC/CC 57%/43% 56%/42% N.S. SC source BM/PB 20%/80% 22%/78% N.S. ATG/ALG 15% 46% <0.001 in vivoüT-cellüdepletion 12% 20% 0.03 ex vivoüT-cellüdepletion 5% 12% 0.03 ASCT. Autologous stem cell transplantation; PS. Performance status; RIC. Reduced intensity conditioning; CC. Conventional conditioning; SC. Stem cell; BM. Bone marrow; PB. Peripheral blood; ATG/ALG. Anti-thymocyte globulin/ALG. Anti-lymphocyte globulin. Disclosures: No relevant conflicts of interest to declare.

PURPOSE:Allogeneic stem-cell transplantation (alloSCT) is a curative therapeutic option for patients with low-grade lymphoid malignancies. Information regarding alloSCT in Waldenström macroglobulinemia (WM) is limited. This study presents the long-term outcome of a large series of patients with WM treated with alloSCT.PATIENTS AND METHODS:A total of 86 patients received allograft by using either myeloablative (MAC; n = 37) or reduced-intensity conditioning (RIC; n = 49) regimens and were retrospectively studied. The median age was 49 years (range, 23 to 64 years); 47 patients had received three or more previous lines of therapy, and eight patients had experienced failure on a prior autologous stem-cell transplantation. A total of 59 patients (68.6%) had chemotherapy-sensitive disease at the time of alloSCT. Median follow-up of the surviving patients was 50 months (7 to 142 months).RESULTS:Nonrelapse mortality (NRM) at 3 years was 33% for MAC and 23% for RIC. The overall response rate was 75.6%. The relapse rates (RRs) at 3 years were 11% for MAC and 25% for RIC. Fourteen patients received donor lymphocyte infusions (DLIs) for disease relapse. PFS and OS at 5 years were 56% and 62% for MAC and 49% and 64% for RIC, respectively. The occurrence of chronic graft-versus-host disease (cGVHD) was associated with a higher NRM and a lower RR, leading to an improvement in PFS.CONCLUSION:alloSCT can induce durable remissions in a selected population of young and heavily pretreated patients with WM. The low RR, the achievement of additional disease responses after DLIs, and the lower RR in patients developing cGVHD suggest the existence of a clinically relevant graft-versus-WM effect.

Abstract Abstract 1196 Poster Board I-218 Introduction: Allogeneic hematopoietic stem cell transplantation (alloSCT) from volunteer unrelated donors (URD) may be associated with a higher non-relapse mortality (NRM) and worse outcome as compared to alloSCT using HLA-identical sibling donors. However, many parameters next to donor type define NRM. The impact on outcome of allele-matching for HLA-A, -B, -C and -DRB1 between donor and recipient has clearly been demonstrated. The prognostic impact of the EBMT risk score, that takes into account age, stage of disease, time from diagnosis to transplantation, donor type and donor-recipient gender combination, has recently been validated in a variety of hematological malignancies including acute leukemia and myelodysplastic syndrome (MDS). We evaluated the relative prognostic value of high-resolution HLA matching and the EBMT risk score for patients with poor-risk acute leukemia and MDS who received an URD transplant. Patients and methods: Between 1987 and 2006, 327 patients (≥16y) with poor-risk acute leukemia and MDS underwent URD alloSCT in the Netherlands. Patients were in 1st complete remission (CR1, n=129), 2nd CR (CR2, n=91), beyond CR2 or not in remission (n=107). The leukemia-risk was considered to be poor if patients had adverse cytogenetics or were not in CR1. The majority of the grafts was T-cell depleted (94%). High-resolution typing of HLA-A, -B, -C, and -DRB1 alleles was available for analysis in 270 donor-recipient pairs and had in part been performed retrospectively. Results: We evaluated the impact of high-resolution matching for HLA-A, -B, -C and -DRB1 on progression free survival (PFS) and overall survival (OS). Patients who were fully matched (8/8) with their donors (n=170) hadsignificantly superior PFS (40+/-4% vs 26+/-5%, hazard ratio (HR)=0.68; 95%CI 0.50–0.92, p=0.01) and OS (39+/-4% vs 29+/-5%, HR=0.70; 95%CI 0.51-0.96, p=0.03), compared to patients with mismatched (≤7/8) donors (n=100). Superior OS in the 8/8 group appeared to be due to a lower NRM (24+/-4% vs 39+/-5%, HR=0.54; 95%CI 0.35-0.85, p=0.008), while the relapse mortality rate was identical in both groups (37+/-4% vs 32+/-5%). Patients with EBMT risk scores of 1-2 (n=71), 3 (n=77), 4 (n=76) and 5-7 (n=103) had a predicted 5 year OS of 52%, 41% (HR=1.57; 95%CI 0.98-2.52), 29% (HR=2.07; 95%CI 1.32-3.26) and 19% (HR=2.69; 95%CI 1.76-4.11), respectively (p<0.001). Relapse mortality rate and NRM increased with increasing EBMT risk score. As shown in the table, the impact of allele-matching on OS was most evident in the EBMT low-risk group. EBMT low-risk (1-2) patients with 8/8 donors showed excellent 5 year OS compared to EBMT low-risk patients with ≤7/8 donors (73+/-8% vs 35+/-12%). The favorable impact of a fully matched donor was absent in patients with higher EBMT risk scores. Conclusions: Both the EBMT risk score and the degree of allele-matching independently predicted outcome after URD alloSCT. The predictive value of allele-matching was especially evident in EBMT low-risk patients, while patients with the highest EBMT risk scores (>4) had a dismal outcome, despite allele-matching. These results emphasize the importance of incorporating age, disease stage, donor-recipient gender combination and time interval from diagnosis to transplantation (EBMT risk score parameters) as well as high-resolution HLA-typing in the risk assessment prior to URD alloSCT. As excellent OS was noted in well matched EBMT low-risk patients, our data underscore the importance of an immediate search for an unrelated donor in poor-risk leukemia patients in CR1 below the age of 40, who should then receive their alloSCT as early consolidation therapy following induction chemotherapy. Disclosures: No relevant conflicts of interest to declare.

SummaryMatched unrelated donor stem cell transplantation (MUD‐SCT) provides the only curative option for patients with follicular lymphoma (FL) who fail conventional therapies and do not have a sibling donor. The purpose of this study was to analyse the outcome of patients with FL treated with MUD‐SCT included in the European Group for Blood and Marrow Transplantation registry. 131 patients treated with reduced‐intensity conditioning (RIC, n = 87) or conventional myeloablative (CONV, n = 44) MUD‐SCT between 2000 and 2005 were included. Median time from diagnosis to MUD‐SCT was 47 months and the median number of previous therapeutic regimens was 4 (previous autograft: 47%). RIC recipients were significantly older, with a longer interval from diagnosis to MUD‐SCT and had failed a previous autograft more frequently than CONV recipients. Non‐relapse mortality (NRM) was 24% and 30% at 100‐d and 1‐year, respectively. After a median follow‐up of 36 months, 17% of the patients developed disease progression, the 3‐year progression‐free survival (PFS) being 47%. Three‐year overall survival (OS) for the whole series was 51%. On multivariate analysis, RIC regimens were associated with at lower NRM and a significantly longer PFS and OS. This retrospective study demonstrated that MUD‐SCT results, even in heavily pre‐treated populations, in a meaningful PFS and OS.

Abstract Abstract 3309 Poster Board III-197 Donor Lymphocyte Infusions (DLI) constitute a potent therapeutic option for treating relapse of chronic myelogenous leukemia (CML) after hematopoietic stem cell transplantation (SCT) inducing durable remissions in the majority of patients. A number of factors is known to influence the efficiency of DLI. A preliminary analysis of EBMT data had suggested that DLI efficiency might be inferior after peripheral blood stem cell transplantation (PBSCT) as compared to DLI following bone marrow transplantation (BMT) (Schmid et al. ASH, 2005). To control for a number of other factors that were not known at the time of the previous analysis, we repeated this analysis based on the results of 357 patients treated with DLI following PBSCT (N=108) and BMT (N=249). We limited the analysis to patients who relapsed after standard intensity conditioning SCT from HLA-identical family donors in first chronic phase of disease. The median age of patients was 39 years (range 18-60) with predominance of males (59%). 53% of patients with known data were CMV positive and in 44% of the patients there was a sex-mismatch with the stem cell donor. SCTs have been performed between 1994 and 2007 (median year: 1998) and the conditioning treatment included total body irradiation (TBI) in 68% and T cell depletion in 44% of patients. 92% of patients with known data achieved complete remission after SCT while grade II-IV acute GvHD occurred in 18% of patients and extensive chronic GvHD in 17% of patients. Median time to relapse was 17 months (range 0.6-129) and median time from SCT to first DLI infusion was 23 months (range 0.6-142). Looking at the patients with known data at the time of first DLI infusion, the relapse could be classified as molecular/cytogenetic in 63%, hematologic in 27% and transformed in 10% of patients. The median year of first DLI was 2000 ranging from 1995 to 2007. As the initial DLI infusion, 9% of patients received <1×10e6, 62% 1.1-10×10e6 and 29% received >10×10e6 CD3+ cells/kg. However, the comparative analysis of groups based on the stem cell source revealed that the group of patients transplanted with PBSCs included significantly more males (68 vs. 56%), were older (median age 42 vs. 39) and underwent more frequently T cell depletion at SCT (72 vs. 34%,). PBSCTs have been performed more recently (median year 1999 vs. 1997) and both duration of remission and time from SCT to first DLI were shorter after PBSCT (median duration: 12 vs. 21 months and 14 vs. 26 months respectively). The initial cell dose in patients from PBSCT arm was significantly lower than in BMT group (≤10×10e6 CD3+/kg in 89% vs. 65% of patients). Similarly to the previous study, we also observed a trend towards superior overall survival after DLI in BMT group compared to PBSCT group, especially in the early post-transplant period. The actuarial probability of survival at five years from DLI was 77% in PBSCT group and 79% in BMT group. However the differences were not statistically significant (p=0.77). The source of stem cells did not influence the occurrence of molecular/cytogenetic remissions after DLI (80% vs. 77%) grade II-IV acute GVHD (16% vs. 16%), chronic GVHD (23% vs. 30%) and myelosuppression (10% vs. 16%). In order to search for factors having impact on survival of analyzed patients, we performed both univariate and multivariate survival analyses. The univariate analysis revealed that interval from SCT to DLI longer than 2 years (p=0.001), date of DLI after 2000 (p=0.026) and molecular/cytogenetic stage of relapse at DLI (p<0.001) were associated with favorable survival. Similarly, the multivariate Cox analysis identified interval between SCT and DLI (HR= 0.50, CI: 0.3-0.8; p=0.01 for after 2 years), date of DLI (HR=0.63, CI:0.4-1.0; p=0.07 for after 1999), and stage of relapse (HR=2.8, CI:1.2-6.5; p=0.02 for HemCR and HR=3.6, CI:1.8-7.0; p<0.001 for missing data group), but not for stem cell source (HR=0.95, CI 0.56-1.6 ;p=0.86) as independent factors affecting survival. Based on our retrospective data from EBMT registry covering a period of 14 years of SCT and DLI, it seems that the PBSCT does not affect the efficiency of DLI compared to BMT. Therefore, keeping all limitations of a retrospective analysis in mind, it seems that differences in efficacy of DLI do not influence the decision whether PBSC or BM should be used as stem cell source for allogeneic SCT in CML in first chronic phase. Disclosures No relevant conflicts of interest to declare.

European Journal of HaematologyVolume 82, Issue 4 p. 326-326 Isolated acral dermatitis due to graft-versus-host disease Walter van der Velden, Walter van der Velden Department of HaematologySearch for more papers by this authorJoost Lesterhuis, Joost Lesterhuis Department of Medical OncologySearch for more papers by this authorWilleke Blokx, Willeke Blokx Department of Pathology, Radboud University Nijmegen Medical Centre, The NetherlandsSearch for more papers by this authorAnton Schattenberg, Anton Schattenberg Department of HaematologySearch for more papers by this author Walter van der Velden, Walter van der Velden Department of HaematologySearch for more papers by this authorJoost Lesterhuis, Joost Lesterhuis Department of Medical OncologySearch for more papers by this authorWilleke Blokx, Willeke Blokx Department of Pathology, Radboud University Nijmegen Medical Centre, The NetherlandsSearch for more papers by this authorAnton Schattenberg, Anton Schattenberg Department of HaematologySearch for more papers by this author First published: 19 February 2009 https://doi.org/10.1111/j.1600-0609.2008.01193.xCitations: 1 Walter van der Velden, Department of Haematology, Radboud University Nijmegen Medical Centre, The Netherlands. Tel: 024-3614762; Fax: +024-3542080; e-mail: [email protected] Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume82, Issue4April 2009Pages 326-326 RelatedInformation

Background: Alloreactive NK cells play a role in tumor eradication after allogeneic HLA mismatched stem cell transplantation (SCT). The effect of NK alloreactivity in HLA identical SCT is still under debate and in particular in transplantation for chronic myeloid leukemia (CIVIL) the data are very limited and with conflicting outcome. The aim of our study was to evaluate the effect of KIR genes and KIR ligands on leukemia free survival (LFS) and relapse rate in a well-defined, homogeneous group of CIVIL patients phase upon HLA identical sibling SCF.Methodology: We retrospectively analyzed the effect of KIRs and KIR ligands (C1 and C2) on LFS and relapse in 70 CML patients in 1st chronic phase, who had received an HLA identical sibling graft. For KIR typing we used a single PCR based KIR typing protocol that also included primers allowing for the identification of the KIR binding site on HLA-Cw (AA 77 and 80).Principal findings: The data show clear differences in transplant outcome between patients having both ligands (C1 and C2) as compared to patients having only one ligand (C1 or C2). In the latter group, the stimulatory KIR2DS5 gene was associated with improved leukemia free survival (p = 0.007; hazard ratio 4.3; 95% confidence interval 1.3-6.7) and lower relapse rates (p = 0.028: HR 4.3,95% CI 1.1-9.1). In contrast, in patients carrying both ligands, KIR2DS5 was associated with reduced LFS (p = 0.0056: HR 0.3; 95% CI 0.1-0.7) and higher relapse rate (p = 0.02; HR 0.35, 95% CI 0.1-0.8).Conclusions: Our data indicate a role for an NK mediated anti-CIVIL response after HLA identical sibling SCT that is influenced by KIR ligands and, more importantly, by stimulatory KIRs present in the donor. (C) 2008 Elsevier Ltd. All rights reserved.

CD8(+) T cells recognizing minor histocompatibility antigens (MiHAs) on leukemic stem and progenitor cells play a pivotal role in effective graft-versus-leukemia reactivity after allogeneic stem cell transplantation (SCT). Previously, we identified a hematopoiesis-restricted MiHA, designated LRH-1, which is presented by HLA-B7 and encoded by the P2X5 purinergic receptor gene. We found that P2X5 is significantly expressed in CD34(+) leukemic subpopulations from chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) patients. Here, we demonstrate that LRH-1-specific CD8(+) T-cell responses are frequently induced in myeloid leukemia patients following donor lymphocyte infusions. Patients with high percentages of circulating LRH-1-specific CD8(+) T cells had no or only mild graft-versus-host disease. Functional analysis showed that LRH-1-specific cytotoxic T lymphocytes (CTLs) isolated from 2 different patients efficiently target LRH-1-positive leukemic CD34(+) progenitor cells from both CML and AML patients, whereas mature CML cells are only marginally lysed due to down-regulation of P2X5. Furthermore, we observed that relative resistance to LRH-1 CTL-mediated cell death due to elevated levels of antiapoptotic XIAP could be overcome by IFN-gamma prestimulation and increased CTL-target ratios. These findings provide a rationale for use of LRH-1 as immunotherapeutic target antigen to treat residual or persisting myeloid malignancies after allogeneic SCT.

Purpose: To evaluate results of high-dose total-body irradiation (TBI) regimens for hematopoietic stem cell transplantation.Methods and Materials: A total of 1,032 patients underwent TBI in one or two fractions before autologous or allogeneic hematologic stem cell transplantation for acute leukemia and non-Hodgkin's lymphoma. The TBI regimens were normalized by using the biological effective dose (BED) concept. The BED values were divided into three dose groups. Study end points were relapse incidence (RI), non-relapse mortality (NRM), relapse-free survival (RFS), and overall survival (OS). Multivariate analysis was performed, stratified by disease.Results: In the highest TBI dose group, RI was significantly lower and NRM was higher vs. the lower dose groups. However, a significant influence on RFS and OS was not found. Relapses in the eye region were found only after shielding to very low doses. Age was of significant influence on OS, RFS, and NRM in favor of younger patients. The NRM of patients older than 40 years significantly increased, and OS decreased. There was no influence of age on RI. Men had better OS and RFS and lower NRM. Type of transplantation significantly influenced RI and NRM for patients with acute leukemia and non-Hodgkin's lymphoma. There was no influence on RFS and OS.Conclusions: Both RI and NRM were significantly influenced by the size of the BED of single-dose or two-fraction TBI regimens; OS and RFS were not. Age was of highly significant influence on NRM, but there was no influence of age on RI. Hyperfractionated TBI with a high BED might be useful, assuming NRM can be reduced. (c) 2008 Elsevier Inc.

Background and Objectives Peripheral blood stem cells (PBSC) following reduced intensity conditioning (RIC) are being increasingly used for allogeneic transplantation in multiple myeloma. The purpose of this study was to compare outcome of patients transplanted with either PBSC or bone marrow (BM) following RIC or myeloablative conditioning (MAC).Design and Methods Data from 1,667 patients who had received an allogeneic identical sibling donor transplant for multiple myeloma from 1994 to 2003 were analyzed. Comparisons were made between results of PBSC and BM transplants after conditioning with RIC or MAC.Results The engraftment rate was faster with PBSC than with BM (median: 14 and 18 days for neutrophils and 15 and 25 days for platelets respectively) irrespectively of whether RIC or MAC was used. The incidence of acute graft-versus-host disease (GVHD) did not differ significantly between the groups while chronic GVHD was more prevalent in PBSC recipients irrespectively of whether they had RIC or MAC. Non-relapse mortality did not differ between PBSC and BM recipients, but was significantly higher in those treated with MAC than in those given RIC irrespectively of the cell source. The relapse/progression rate did not differ between PBSC and BM recipients, but was significantly higher in those given RIC, irrespectively of the cell source. There was no significant difference in overall or progression-free survival between patients given PBSC or BM transplants.Interpretation and Conclusions Although transplantation of PBSC is associated with faster engraftment and more frequent chronic GVHD, overall survival, non-relapse mortality, relapse/progression and progression-free survival are similar to those following BM transplants. However both PBSC and BM transplants are associated with lower non-relapse mortality, lower response rate and higher relapse/progression if RIC is used instead of MAC.

Allogeneic stem cell transplantation (SCT) is a specialized form of immunotherapy for treating patients with hematological malignancies. The curative potential is attributed to the graft-versus-tumor (GVT) response during which donor-derived cytotoxic T lymphocytes (CTL) eliminate malignant cells of the recipient. Minor histocompatibility antigens (MiHA) are the major targets of the GVT response, and expansion of MiHA-specific CTL has been shown to coincide with tumor remission following SCT. Recently, we identified a novel hematopoietic cell-restricted MiHA, designated LRH-1, which is presented by HLA-B7 and encoded by the P2X5 purinergic receptor gene (J. Clin. Invest.2005:115:3506–3516). Interestingly, tetramer analysis showed a direct association between in vivo expansion of LRH-1-specific CD8+ T cells and the disappearance of Bcr-Abl positive tumor cells in the CML patient from whom LRH-1-specific CTL was originally isolated. In addition, we detected in vivo expansion of LRH-1-specific CTL in an AML patient who was in clinical remission without GVHD. Furthermore, we demonstrated that P2X5 mRNA is significantly expressed in leukemic CD34+ progenitor cells from most CML as well as AML patients. These findings indicate a role for LRH-1 in inducing GVT immunity against myeloid leukemic progenitor cells. Here, we investigated the ex vivo responsiveness of myeloid leukemic CD34+ progenitor cells to LRH-1-specific CTL. First, we addressed this question using the CD34+ KG1 cell line which is positive for LRH-1. By using a CFSE-based survival assay we demonstrated that KG1 cells stably transfected with HLA-B7 could be efficiently lysed by LRH-1-specific CTL. Next, we determined responsiveness of purified CD34+ progenitor cells from HLA-B7+ CML patients to LRH-1 CTL-mediated killing. In the CFSE-based survival assay as well as a hematopoietic progenitor cell inhibition assay we showed that LRH-1-specific CTL efficiently recognize and kill CD34+ progenitor cells from LRH-1+ CML patients. In contrast, LRH-1-specific CTL did not inhibit the proliferation of CD34+ progenitor cells from LRH-1- CML patients. These findings illustrate that the P2X5-encoded LRH-1 antigen is an attractive target for adequate eradication of myeloid leukemic progenitor cells after allogeneic SCT.