To Transplant Related Mortality Research Articles

Treatment Dilemmas in Asymptomatic Children with Primary Haemophagocytic Lymphohistiocytosis

IntroductionPrimary haemophagocytic lymphohistiocytosis (HLH) is caused by mutations in genes which affect the exocytosis of apoptotic granules in T/NK cells, hampering their killing function. Once symptomatic, it requires induction treatment based on steroids and chemotherapy or immunotherapy followed by allogeneic stem cell transplantation (SCT). Difficulties in achieving a good remission prior to SCT and high treatment related toxicities have resulted in overall survival (OS) of only 50-60% at 5 years. Primary HLH has an autosomal recessive pattern of inheritance and studies have shown that only 1/3 of the relatives affected by the same genetic mutation as index cases (ICs) have comparable clinical presentations. It is therefore a challenging decision to offer SCT to a patient with a recognized genetic defect that predisposes to HLH but with no clinical symptoms. Our study investigated outcomes of pairs of ICs and asymptomatic family members with a known genetic defect predisposing to primary HLH. The study also analysed therapeutic attitudes towards the asymptomatic cases (ACs) at various international paediatric BMT centres.MethodsPatients <18 years were eligible for this study if they had a mutation in one of the known causative genes for primary HLH, if they were asymptomatic at the time of diagnosis, and if their diagnosis was made after an IC in the family. After appropriate IRB review, data was collected through a questionnaire distributed to centres through the Histiocyte Society.Results19 Centres in Europe and North America were contacted and they reported a total of 28 analysable pairs of ICs and asymptomatic cases (ACs). Of these, 11 had perforin deficiency, 6 Griscelli syndrome type II, 5 MUNC 18-2 deficiency, 3 MUNC 13-4 deficiency, 2 syntaxin deficiency, and 1 Chediak Higashi syndrome.All ICs had overt disease at the time of presentation at a median age of 1.5 years (range 0-11.5). 14/28 (50.0%) had CNS involvement and 6 (21.4%) were refractory to front line treatment. 18/28 (64.3%) underwent SCT. 13 (72.2%) are alive in complete remission (CR). 4 died due to transplant related mortality (TRM) and 1 from disease progression post SCT. 9 (32.1%) did not undergo SCT and received chemo-immuno therapy. Of these, 2 are alive in CR (both with MUNC 18-2 deficiency), 1 was lost to follow up and 6 have died due to disease progression (n=5) or treatment related toxicity (n=1). One child had an undocumented treatment and died from unknown causes. 15/28 (53.6%) of ICs are alive at a median follow up of 3 years from diagnosis (range 0.1-11).Median age of ACs at diagnosis was 0.7 years (range 0-15). Of these, 9/28 (32.1%) activated HLH whilst on observation/waiting for SCT and 2 (22.2%) required multiple lines of treatment to achieve remission. 8 patients underwent SCT; 5 are alive in CR and 3 died (2 from disease progression and 1 from TRM). The remaining patient was on treatment with HLH04 protocol when he was lost to follow up. Of the remaining 19 ACs, 6 have received no specific treatment and are being monitored. They are all alive in CR. 13 underwent SCT as a pre-emptive measure and 12 are alive in CR at a median follow up of 37 months, 1 died of SCT unrelated causes 12 months post SCT whilst in CR.Of 27 evaluable ACs, 23 (82.1%) are alive at a median follow up of 3 year from diagnosis (0.6 to 11). 17/21 patients who underwent SCT are alive (81.0%). 12/13 (92.3%) transplanted before the development of HLH are alive compared to 5/8 (62.5%) transplanted after HLH development (p=0.25)OS for ACs was significantly higher than for ICs irrespective of treatment (82.1% vs 53.6%, p=0.02). There was no survival difference according to the underlying genetic defect. Based on their clinical experience, 80% of the reporting centres would favour elective SCT in future ACs, 10% would adopt a careful ‘wait and watch’ policy and 10% would be guided by the severity of presentation in the index case.ConclusionIn our study ACs had a significant survival advantage especially if transplanted before the development of HLH, where survival was nearly 100%. Most transplant centres are adopting the approach of pre-emptive SCT. This information will be very valuable for physicians and families faced with this difficult decision. DisclosuresLucchini:Alexion: Membership on an entity's Board of Directors or advisory committees.

Successful Treatment of Mature T-Cell Lymphoma with Allogeneic Stem Cell Transplantation: The Largest Multicenter Retrospective Analysis

Successful Treatment of Mature T-Cell Lymphoma with Allogeneic Stem Cell Transplantation: The Largest Multicenter Retrospective Analysis

Pentaglobin® Efficacy in Reducing the Incidence of Sepsis and Transplant-Related Mortality in Pediatric Patients Undergoing Hematopoietic Stem Cell Transplantation: A Retrospective Study.

The 12-month mortality rate in patients undergoing hematopoietic stem cell transplantation (HSCT) remains high, especially with respect to transplant-related mortality (TRM), which includes mortality due to infection complications through the aplasia phase. The aim of this study was to determine whether the administration of Pentaglobin® could decrease TRM by lowering sepsis onset or weakening sepsis through the aplasia phase. One hundred and ninety-nine pediatric patients who had undergone HSCT were enrolled in our retrospective study. The patients were divided into two groups: the Pentaglobin group, which had received Pentaglobin® in addition to the standard antibiotic treatment protocol established for the aplasia phase, and the Control group, which received only the standard treatment. As compared to the control group outcome, Pentaglobin® led to a significant decrease in the days of temperature increase (p < 0.001) and a reduced infection-related mortality rate (p = 0.04). In addition, the number of antibiotics used to control infections, and the number of antibiotic therapy changes needed following first-line drug failure, were significantly lowered in the Pentaglobin group as compared to the control group (p < 0.0001). With respect to the onset of new infections following the primary infection detected, the Pentaglobin group showed a significant reduction for bacterial events, as compared to the control group (p < 0.03). Pentaglobin® use in patients undergoing HSCT seems to produce a significant decrease in infection-associated TRM rate.

Next Generation Sequence Minimal Residual Disease (NGS-MRD) Predicts Event Free Survival (EFS) Irrespective of Hematopoietic Cell Transplantation (HCT) Conditioning Regimen, Graft Αβ T and B-Cell Depletion or Patient Weight Category in Children with Acute Lymphoblastic Leukemia (ALL)

MRD detected by flow cytometry (FC) or PCR has been associated with key outcomes after HCT for ALL. In a prospective multicenter trial (NCT02646839; Pediatric Blood and Marrow Transplant Consortium [PBMTC] ONC1401), we performed a planned analysis of NGS-MRD to predict outcomes pre- and post-HCT for ALL patients (n=57, median follow-up 523 [range 58-1198] days post-HCT). We evaluated baseline blast samples from 74 patients for dominant BCR/TCR rearrangements and to follow MRD by NGS. Dominant clones were identified in 100% of B-ALL patients, 96.8% (61/63) in BCR and 3.2% in TCR gamma. For T-ALL patients, clones were identified in 62.7% (7/11), with the remaining 37.3% being polyclonal. Patients proceeded to HCT only if they were in morphological remission. Pre-HCT NGS-MRD from bone marrow (BM) was highly predictive of EFS (n=29 P=0.027, Figure 1) and NGS-MRD from peripheral blood (PB) trended similarly (n=27, P=0.17, Figure 2). In BM NGS-MRD negative patients, relapse was exceptionally low with all events due to transplant related mortality (TRM). There did not appear to be a benefit of acute (Figure 3) or chronic graft-vs-host-disease (GVHD) in NGS-MRD- patients. Pre-HCT, 10% of the BM samples were MRD+ by FC, but 35% were MRD+ by NGS. Direct comparison of NGS-MRD in BM and PB with FC MRD pre- and post-HCT showed improvements in positive and negative predictive power. Αβ-T and B-cell depleted haploidentical grafts had similar outcomes to other stem cell sources (Figure 4) with decreased incidence of GVHD [aGVHD > grade 2: n=1 (3.3%) and extensive cGVHD: n=1(3.3%)]. TBI (total body irradiation) based myeloablative conditioning (TBI/TT [Thiotepa]/CY [Cyclophosphamide], TBI/CY, or TBI/VP16; ± anti-thymocyte globulin [ATG]) and non-TBI reduced toxicity (Flu [Fludarabine]/Mel [Melphalan]/TT; ± ATG) had similar EFS (P= 0.31). TRM was very low 8.7% (n=5) in this population (n=57)) and rescue of relapse was high for the duration of follow up to date, resulting in similar OS for MRD- vs. MRD+ patients (P= 0.15), likely due to rescue with cell/immunotherapy. We examined the interaction of obesity, using body mass index (BMI) based on height/weight, pre-HCT, in the context of NGS-MRD on EFS. The BMI was converted to a percentile through population norms for age, gender, and defined thresholds published by the Centers for Disease Control and prevention (CDC). Lean patients (< 85th percentile [%]) overall had better survival than the overweight (OW)/obese (85-94%/≥95%) (Figure 5: P=0.016). Among the lean patients, NGS-MRD was prognostic, with NGS-MRD+ patients having worse EFS. This was also observed with the OW/obese group, where being NGS MRD+ led to dismal survival. Overweight/Obese patients who were pre-HCT MRD- had survival similar lean/MRD+ patients. Thus, both factors, weight category and NGS-MRD influenced EFS (Figure 6: P=0.02).

Next Generation Sequence Minimal Residual Disease (NGS-MRD) Predicts Outstanding Event Free Survival (EFS) Regardless of Hematopoietic Cell Transplantation (HCT) Preparative Approach or Graft Alpha/Beta Depletion in Children with Acute Lymphoblastic Leukemia (ALL)

MRD detected by flow cytometry (FC) or PCR has been associated with key outcomes after HCT for ALL. In a prospective multicenter trial (NCT02646839; Pediatric Blood and Marrow Transplant Consortium [PBMTC] ONC1401), we performed a planned sub-study of NGS-MRD to predict outcomes pre- and post-HCT for ALL patients (n=57, median follow-up 523 [range 58-1198] days post-HCT). In addition, we performed analyses of relevant clinical factors to assess their relationship to EFS. The larger trial studying the role of KIR favorable haploidentical vs. other transplantation approaches for children diagnosed with ALL, acute myeloid leukemia and myelodysplastic syndrome will be reported separately. We evaluated baseline blast samples from 74 patients for dominant BCR/TCR rearrangements and to follow MRD by NGS. Dominant rearrangements were identified in 100% of B-ALL patients, 96.8% (61/63) in BCR and 3.2% in TCR gamma. For T-ALL patients, rearrangements were identified in 62.7% (7/11), with the remaining 37.3% being polyclonal. Patients proceeded to HCT only if they were in morphological remission. Pre-HCT NGS-MRD from bone marrow (BM) was highly predictive of EFS (n=29 P=0.027, Figure 1) and although NGS-MRD from peripheral blood (PB) did not reach statistical significance due to decreased sample size (n=27, P=0.17, Figure 2), it trended similarly. In BM NGS-MRD negative patients, relapse was exceptionally low with all events due to transplant related mortality (TRM). There did not appear to be a benefit of acute graft-vs-host-disease (aGVHD) in NGS-MRD- patients (Figure 3) or chronic (c)GVHD, but sample size was a limitation. Pre-HCT, 10% of the BM samples were MRD+ by FC, but 35% were MRD+ by NGS. Direct comparison of NGS-MRD in BM and PB with FC MRD pre- and post-HCT showed improvements positive and negative predictive power (data not shown). Alpha/beta depleted haploidentical grafts had similar outcomes to other stem cell sources (Figure 4) with decreased incidence of GVHD [aGVHD &gt; grade 2: n=1 (3.3%) and extensive cGVHD: n=1(3.3%)]. TBI (total body irradiation) based myeloablative conditioning (TBI/TT [Thiotepa]/CY [Cyclophosphamide], TBI/CY, or TBI/VP16; ± anti-thymocyte globulin [ATG]) and non-TBI reduced toxicity (Flu [Fludarabine]/Mel [Melphalan]/TT; ± ATG) had identical EFS (P= 0.31). TRM was very low 8.7%(n=5) in this population (n=57)) and rescue of relapse was high for the duration of follow up to date, resulting in similar OS for MRD- vs. MRD+ patients (P= 0.15), likely due to rescue with cell/immunotherapy. We next examined the interaction of obesity, using body mass index (BMI) based on height/weight pre-HCT, in the context of NGS-MRD on EFS. The BMI score was converted to a percentile through population norms for age and gender and defined thresholds published by the Centers for Disease Control and prevention (CDC). Lean patients (&lt; 85th percentile [%]) overall had better survival than the overweight (OW)/obese (85-94%/≥95%) (Figure 5: P=0.016). But among the lean patients, NGS-MRD still had an effect, with NGS-MRD+ patients had poorer EFS. Same was observed with the OW/obese group, where being NGS MRD+ adds further reduction in survival. Overweight/Obese patients who were pre-HCT MRD- had survival closer to the lean/MRD+ patients. We observed decreased EFS by weight category and NGS-MRD (Figure 6: P= 0.02). In conclusion, NGS-MRD was highly predictive for EFS regardless of HCT preparative approach or graft Alpha/Beta Depletion. NGS improved predictive power for MRD positivity compared to FC. NGS was able identify rearrangements suitable for MRD tracking in all B-ALL and in most of T-ALL samples. In BM NGS-MRD negative patients, relapse was exceptionally low. There did not appear to be a benefit of aGVHD or cGVHD in NGS-MRD- patients. Alpha/beta depleted haploidentical grafts had similar outcomes to other stem cell sources with decreased incidence of severe GVHD. We observed decreased EFS by weight category and NGS-MRD. Lean patients had better survival, after HCT, than OW/Obese patients. But among the lean patients, NGS-MRD+ patients had poorer EFS. Disclosures Abdel-Azim: Adaptive: Research Funding. Dvorak:Jazz Pharmaceuticals: Consultancy; Alexion Inc: Consultancy. Bunin:PRA Health Sciences: Other: Immediate family member employed. Walters:Editas Medicine: Consultancy; TruCode: Consultancy; AllCells, Inc: Consultancy. Cairo:Jazz Pharmaceuticals: Other: Advisory Board, Research Funding, Speakers Bureau; Miltenyi: Other: MTA; Osuka: Research Funding. Kitko:Novartis: Consultancy, Honoraria; Mallinckrodt: Honoraria. Jacob:Adaptive Biotechnologies: Employment, Other: shareholder. Wing:Miltenyi Biotec: Employment. Pulsipher:Medac: Honoraria; Miltenyi: Research Funding; Bellicum: Consultancy; Amgen: Other: Lecture; CSL Behring: Membership on an entity's Board of Directors or advisory committees; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Jazz: Other: Education for employees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Survival Outcomes Following Allogeneic Stem Cell Transplantation for Inherited Bone Marrow Failure and Myeloid Germline Predisposition Syndromes

Introduction: Allogeneic stem cell transplant (HCT) is the only potential curative option for patients with inherited marrow failure (iBMF) and myeloid germline predisposition syndromes (GPD). HCT outcomes are influenced by inherent disease specific-nuances such as alkylating agent and radio-sensitivity, immune deregulation, and higher risks for graft failure and GVHD; factors contributing to transplant related mortality (TRM) and morbidity. We carried out this retrospective study to assess survival outcomes and long term complications (LTC) in patients with IBMF and GPD that underwent HCT. Patients and methods: We queried our institutional database and identified patients with iBMF and GPD as defined by the 2016 WHO classification. These included Fanconi anemia (FA), short telomere syndromes (STS), Diamond-Blackfan anemia (DBA), GATA2 and RUNX1 haploinsufficiency, congenital amegakaryocytic thrombocytopenia (CAMT), deficiency of adenosine deaminase 2 (DADA2), among others. Patients with acquired causes of BMF were excluded. Statistical analyses were performed using SAS (JMP v14.1). Results: Twenty eight patients, median age 10 years (1 month-63 years), 46% males, were included in the study (table 1). Fanconi anemia Seven (25%) patients with FA underwent HCT, 5 (71%) without myeloid transformation and 2 after transformation to MDS/AML. Five (71%) patients received a RIC, 4 (57%) prior to transformation. At a median follow up (FU) of 126 m, the median OS was 194 m (95% CI 34m; NR) and 10 year survival was 64%. Grade 1 aGVHD was seen in four (57%) and 3 (42%) developed mild cGVHD, while 1 developed a donor derived AML (sibling not tested for FA). LTC included second primary malignancy (SPM) - squamous cell cancer (SCC) of skin and muscle invasive bladder cancer (MIBC) in 1(14%) and SCC of head/neck and anogenital region in 3 patients (43%), psychosocial complications (PS) in 6(85%), premature ovarian failure (POF) in 3(43%), and avascular necrosis (AVN) in 4(57%) patients. Short Telomere Syndromes (STS) Seven patients with STS underwent HCT, 2 (28%) after transformation to MDS. Five (71%) received RIC, including both the transformed patients. At a median FU of 67m, median OS was NR (95% CI 2m; NR) and 5 year survival was 47%. One (14%) patient developed grade 2 aGVHD and mild cGVHD of skin. Three (43%) developed SPM - skin cancers in 2 and MIBC in 1. PS was noted in 1(15%), and AVN in 3(43%). Three (43%) patients had concomitant mild IPF/restrictive lung disease. GATA2 haploinsufficiency : Seven patients with GATA2 haploinsufficiency underwent HCT; 2(28.5%) after transformation to MDS and 3(43%) to AML, of which 2(40%) received MAC. At a median FU of 57m, median OS was NR (95% CI 7m; NR) and 5 year survival was 71%. Three (50%) developed grade 2 aGVHD of skin and GI tract and 2(33%) developed mild cGVHD. LTC include PTLD, AVN and POF in 1 patient each. Ribosomopathies : One patient (13y) with DBA underwent RIC HCT and developed grade 2 aGVHD, secondary iron overload, and died at 10 months due to severe fungal infection. Others : Identical twins with CAMT underwent HCT (at 4y and 5y) from the same unrelated donor and at last FU (74m and 87m, respectively) remain 100% donor without GVHD. Two children with primary immunodeficiency and marrow failure underwent HCT (at 2y and 7y), one after transformation to MDS. The non-transformed patient is currently alive (120m), while the patient with transformation died 1month after HCT from disseminated cytomegalovirus infection. One patient with germline RUNX1 deletion developed CMML and underwent a RIC HCT and is alive at a FU of 4 months, with no GVHD. One patient with DADA2 (n=1) underwent RIC HCT without LTC. Due to the smaller cohort size, we compared OS in transformed and non-transformed patients for the IBMF and GATA2 patients only (n=24, 9 with transformation) (figure1). At a median FU of 74m, the median OS of transformed vs non-transformed patients was 108m(95% CI 1;108m) and 163m(95% CI 67m; NR), respectively (p=0.033). Conclusions: Our study demonstrates that HCT remains an important intervention for IBMF and GPD, with the maximum impact being gained prior to transformation. While only mild chronic GVHD was noted (37%), inherent syndromic issues resulted in a high rate of SPM (FA/STS) and organ failure (STS- IPF). Notably, one FA patient who received an MRD HCT developed donor derived AML, underlining the importance of genetic screening in asymptomatic related individuals. Disclosures Kenderian: Lentigen: Research Funding; Kite/Gilead: Research Funding; Morphosys: Research Funding; Humanigen: Other: Scientific advisory board , Patents &amp; Royalties, Research Funding; Novartis: Patents &amp; Royalties, Research Funding; Tolero: Research Funding. Patnaik:Stem Line Pharmaceuticals.: Membership on an entity's Board of Directors or advisory committees.

Haploidentical HCT using an αβ T-cell-depleted graft with targeted αβ(+) cells by add-back after a reduced intensity preparative regimen containing low-dose TBI.

Between 2012 and 2015, 42 pediatric patients underwent haploidentical hematopoietic cell transplantation using an αβ(+) T-cell-depleted graft with targeted αβ cells at 1-5 × 10(5)/kg by add-back; 31 had hematologic malignancy (HM), 8 had non-malignant disease (NM) and 3 had solid tumors. All patients received uniform reduced-intensity conditioning with fludarabine, cyclophosphamide, rabbit anti-thymocyte globulin and low-dose TBI. All 42 patients achieved neutrophil engraftment at a median of 10 days. The cumulative incidences (CIs) of ⩾grade II and ⩾grade III acute GvHD were 31±7.1% (SE) and 12±5.0%, respectively, and 1-year CI of chronic GvHD was 15±5.8%. One patient died of CMV pneumonia, leading to transplant-related mortality (TRM) of 2.6±2.5%. Sixteen patients relapsed and 11 died of disease. At a median follow-up of 19 months (range, 5-43 months), the estimated 2-year event-free survival for NM and HM were 88±11.7 and 50±10.1%, respectively. Our study demonstrated that haploidentical hematopoietic cell transplantation after ex vivo depletion of αβ(+) T cells with targeted dose noticeably reduced the graft failure rate and TRM in pediatric patients and could be applied to patients lacking a suitable related or unrelated donor.

Predictive Value of Minimal Residual Disease: Analysis By Flow-Cytometry in Children with Relapsed Acute Lymphoblastic Leukemia

Introduction: Despite the advances observed in the outcome of pediatric acute lymphoblastic leukemia (ALL) treatment during the last 20 years, relapse remains the most common cause of treatment failure in childhood ALL. Several factors have been associated to the prognosis of these patients; however, minimal residual disease (MRD) emerges as a relevant predictor of outcome.Objectives: The aims of this study were to assess MRD by flow-cytometry in relapsed ALL and to evaluate its prognostic impact as a predictor factor of outcome at the end of the induction therapy and prior to hematopoietic stem cell transplantation (HSCT).Patients and Methods: From Aug'10 to Jun'15, 123 ALL patients were treated at our center. MRD determination at least at two time-points during relapse treatment was a requirement for considering a patient eligible for the present study. Sixty-six cases were excluded due to the following causes: 10 patients died during induction, 2 died early in complete remission (CR), 29 did not respond to chemotherapy, in 13 patients MRD determination was not performed: 4 did not have clinical data available, 4 patients were Down Syndrome and 4 children received treatment for relapse in other centers. Thus, fifty-seven patients achieved CR and were evaluated for MRD at two time points. Of them, 56 patients belonged to S4 and S3 and 1 patient to S1 group as defined by the Berlin-Frankfurt-Münster stratification for relapsed ALL. MRD was analyzed by multiparametric flow-cytometry following ALL-IC 2009 guidelines. Negative MRD was defined as disclosing less than 0.1% of blasts. For this analysis, patients were stratified based on MRD levels at two different time points: after end of induction, before HSCT or at any other time point during the follow-up for patients who did not undergo HSCT. Three groups were defined: Group-1: negative at both time points (n= 23), Group-2: positive at 1 time point (n= 13) and Group-3: positive at both time points (n= 21). Patients who relapsed before receiving HSCT were considered Group-3. Twenty-five patients underwent HSCT: 13 of them from Group-1, 9 from Group-2 (2 had positive MRD previous to receive HSCT) and 3 patients from Group-3. HSCT was performed with matched familiar donor in 16 cases and matched unrelated donor in 9 cases.Results: The distribution of events according to receiving or not HSCT was: 5 died due to transplant related mortality (TRM), 9 relapsed after receiving HSCT and 16 during treatment with chemotherapy. With a median follow-up of 16 (range: 6-67) months, overall 3-year EFS probability (EFSp) (SE) was 32 (8)%. The 3-year EFSp was 75 (11)% for Group-1, 24 (14)% for Group-2 and 0% for Group-3 (p-value <0.00001). Comparing patients who did not receive HSCT vs. patients who did, EFSp (SE) was 32 (12)% and 29 (11)% respectively (p-value: non-significant). The EFSp (SE) according to MRD groups in patients who underwent HSCT was: Group-1: 53 (19)%, Group-2: 14 (13)% and 0% for Group-3 (p-value: 0.06).Conclusions: MRD quantification by flow-cytometry demonstrated to be a significant prognostic factor for relapsed ALL. Both, TRM and death in CR rates, were high and should be decreased by improving supportive measures. MRD determination by flow-cytometry in patients who underwent HSCT showed a trend to achieve a better EFSp, thus representing a relevant tool for stratifying relapsed ALL patients in order to achieve a better selection of patients to receive HSCT. DisclosuresNo relevant conflicts of interest to declare.

IgM anti-recipient ABO antibodies predict acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation

Passenger lymphocyte syndrome (PLS) presents as transient immune hemolysis due to anti-recipient ABO antibodies produced by donor B-lymphocytes accompanying minor or bidirectional ABO incompatible allogeneic hematopoietic stem cell transplantation (HSCT). We monitored both IgM and IgG type anti-recipient ABO antibodies in 18 consecutive HSCT recipients with hematological malignancies. Five of these patients (28%) developed transient immune hemolysis due to PLS after a median of 19 days post-HSCT. This response was associated with the detection of IgM and IgG anti-recipient ABO antibodies after a median of 16 and 22 days post-HSCT, respectively. All five patients subsequently developed acute graft-versus-host disease (GVHD) grades II-IV, and three died due to transplant-related mortality (TRM) within 1 year after HSCT, while in contrast, of the 13 patients without PLS, three (23%) developed grades II-IV acute GVHD (p < 0.01) and the 1-year TRM was 8% (p = 0.03). Thus, patients with PLS had a significantly lower 1-year overall survival than those without PLS (20 vs. 75%, p = 0.03). These findings suggest that the IgM anti-recipient ABO antibody may be an early predictor of acute GVHD and poor survival after minor or bidirectional ABO incompatible HSCT.

Let us think about lymphocyte counts!

In this issue of our journal, our colleagues Juliane Morando, Sergio Costa Fortier, Ricardo Pasquini, Jose Zanis Neto and Carmem Maria Sales Bonfim from the Bone Marrow Transplantation Unit of the Hospital de Clinicas, Universidade Federal do Parana describe an interesting retrospective study of 137 under 21-year-old acute leukemia patients accumulated over 23 years(1995 to 2008)(1). Previous studies have already shown that lymphocyte recovery is correlated to transplant-related mortality (TRM), relapse rate and overall survival(2-4). The authors analyzed the outcome of their patients considering the lymphocyte counts on Days +30 and +100.

Stem Cell Transplantation in Elderly Patients with Acute Lymphoblastic Leukemia (ALL) in First Complete Remission (CR1).

In the German Multicenter ALL studies (GMALL) patients aged >55 years with high risk (B-lineage ALL with WBC at diagnosis >30000, late CR, t (4; 11), complex aberrant karyotype or prae-T or mature T-ALL) or very high risk (Ph+/BCR-ABL+) ALL are increasingly candidates for allogeneic stem cell transplantation (allogeneic SCT with a HLA identical sibling donor, MRD or a matched unrelated donor, MUD) or autologous SCT. Here, we report on 31 elderly patients transplanted within the GMALL studies 06/99 and 07/03. Median age of the patients was 61 years (56–65). 22 patients belonged to the very high risk group (VHR), 8 patients to the high risk group (HR) and 1 patient from the standard risk group (SR) was transplanted because of detection of minimal residual disease.17/31 patients were transplanted from a matched unrelated donor, 9/31 patients from a HLA identical sibling donor and 5/31 patients underwent autologous SCT. Conditioning regimens for MRD SCT were myeloablative (MAC) in 6 patients (TBI 12 Gy and chemotherapy n=2, radioimmunotherapy + chemotherapy n=2, chemotherapy only n=2) and 3 patients received reduced intensity conditioning (RIC).Conditioning regimens for MUD SCT changed over time with an increasing number of RIC in the study 07/03. In total, 7/17 patients received MAC (TBI 12 Gy and chemotherapy n=5, chemotherapy only n=2) and 10/17 patients received RIC. Conditioning regimens in autologous SCT were myeloablative (MAC) in 5/5 patients.Results: After allogeneic MRD SCT 4/9 patients (44%) are alive in CCR (d+ 24, d+ 611, d+ 1721, d+ 2321), 3/9 patients died due to leukemia, 2/9 due to transplant related mortality (TRM). After allogeneic MUD SCT 8/17 patients (46%) are alive in CCR (from d+ 165 to d+ 2176). 1 further patient is alive after re- SCT for treatment of relapse. 7/17 patients died due to TRM and 1 patient died due to relapse. After autologous SCT 2/5 patients are alive in CCR (d+ 1703, d+ 1731), 3/5 died due to relapse. Risk factors for TRM: In allo SCT and MAC 8/13 patients died due to TRM in contrast to 1/13 patients with RIC. In auto SCT none of the patients died due to TRM. Risk factors for relapse: In allogeneic MRD SCT 3/9 patients died due to relapse and 2/17 patients relapsed after MUD SCT. Due to the small number of patients, no difference between MAC and RIC could be found. In autologous SCT 3/5 patients died due to relapse.In conclusion: The study shows that allo MRD but also MUD SCT is very effective in a selected population of elderly ALL patients. Since the survival of elderly patients with chemotherapy only is about 25%, more patients should be encouraged to have a MRD or MUD SCT.

Chimerism Analyses in Stem Cell Recipients with Non Hodgkin Lymphoma

Increasing numbers of patients with Non Hodgkin Lymphoma receive allogeneic stem cell transplantation (SCT) due to progressive disease or relapse after standard therapy protocols or after autologous stem cell transplantation. However, depending on the entity, variable proportions of lymphoma patients develop relapse after SCT. For the earliest detection of relapse with respect to immunotherapeutic approaches, monitoring of chimerism provides an option, but most studies were performed in patients with acute leukemias. This retrospective single-center analysis evaluated the performance of chimerism as assessed either by restriction length fragment polymorphisms (RFLP) or by quantitiative real-time PCR for nine different genetic polymorphisms (Alizadeh et al., 2001) and for Y-specific sequences (Fehse et al., 2001) in thirteen patients with mantle cell lymphoma after SCT. Allo-SCT was performed from related and unrelated donors (Jan 2000–Dec 2006) at the Interdisciplinary Clinic for Stem Cell Transplantation of the University of Hamburg, Germany. Thirteen patients received fourteen allo-SCTs (in one case due to relapse after allogeneic SCT being followed by a second SCT from a second donor). One patient received a stem cell boost after graft failure following SCT. There were eleven males and two females (median age: 52 years; range: 36–62 years). Four patients had Ann-Arbor Stage IIIA, eight had stage IVA–B (in one case the previous stage was unknown). Before allo-SCT, three cases were in complete remission, six in partial remission, two had progressive disease, and one case showed stable disease (data missing in one case). Four allo-SCTs were from related donors, nine from unrelated donors. Donors and recipients showed HLA-match in eleven transplantations and mismatch in two SCTs. At the time of this report, six patients were alive and in complete remission (6/13; 46%), four died due to transplant related mortality (TRM) (31%), and three due to relapse/progression of the lymphoma (23%). Median overall survival (OS) was 460 days (range 53–1380 days); median disease free survival (DFS) was 210 days (range: 49–1380 days). After SCT, all thirteen stem cell recipients achieved complete donor chimerism (being defined by >99.9% of donor cells). In eleven cases chimerism was stable, in seven cases in association to stable long-time remissions with a median of 145 days (range 36–1380 days). Five patients developed relapse with a median interval of 132 days after SCT (range 49–924 days), and one further patient achieved partial remission only. Four relapse cases maintained complete donor chimerism; only one of the five relapse patients had a significant decrease of donor chimerism on day +38 from 100% to 70%, while relapse was diagnosed on day +49. The patient with partial remission had complete loss of donor chimerism on day +171. This study points to the conclusion that measurement of chimerism as single diagnostic method in patients with NHL who undergo allogeneic SCT might not be as effective for early detection of relapse when compared to other hematological malignancies such as acute leukemias. Although the limited sample size of this study has to be considered, it should be investigated whether the combination of chimerism analyses with minimal residual disease detection as the specific reciprocal rearrangements e.g. BCL1-IgH in MCL might improve the early detection of relapse after SCT.

Treatment of Steroid-Resistant Graft-Versus-Host Disease with Monoclonal Antibodies in Children.

Acute graft-versus-host disease (aGVHD) carries a major risk of morbidity and mortality in patients undergoing hematopoietic stem cell transplantation (HSCT). The prognosis is poor if aGVHD does not respond to corticosteroid treatment. Recently, monoclonal antibodies such as daclizumab, a humanized monoclonal IgG1, and infliximab, a chimeric monoclonal antibody that binds the precursor of tumor-necrosis factor-alfa, have shown promising results in the treatment of corticosteroid-resistant aGVHD. The reported response rate to monoclonal antibody therapy in adults with aGVHD reaches as high as 67%. Data describing the efficacy of monoclonal antibodies in children with corticosteroid-resistant aGVHD are limited. We conducted a retrospective analysis to evaluate the efficacy of daclizumab and/or infliximab in children diagnosed with steroid-resistant aGVHD in the Hospital for Sick Children, Toronto, from July 2002 to December 2005. Corticosteroid-resistant aGVHD was defined as aGVHD which did not respond or worsened after a minimum of 5 days of corticosteroid therapy. Complete response was defined as full recovery without any signs of aGVHD; partial response was defined as improvement of aGVHD symptoms in at least one organ without worsening in other organs. Sixteen children were treated for aGVHD, thirteen of them had aGVHD grade 3 or 4. The organs involved were gut (n=6), skin (n=4), liver (n=2) and multi-organ involvement (n=4). Thirteen children were given daclizumab; one was treated with infliximab and 2 children with their combination. Fourteen children received a full course of monoclonal antibodies for aGVHD. An additional child died after the first dose (from multi-organ failure) and one child developed reactive arthritis attributed to daclizumab. Seven of the 14 children (50%) who completed treatment responded: 5 had complete response and 2 had a partial response. Nine out of the 16 children died during the study period: 8 due to Transplant Related Mortality (TRM) and 1 due to relapse; three children developed fatal fungal infection and one had fatal adenovirus infection during or shortly after monoclonal antibody treatment. Median length of follow up in the remaining 7 patients was 18 months. We conclude that monoclonal antibodies were effective in the treatment of children with corticosteroid-resistant acute GVHD. The risk for infection, mainly fungal, was high.

Efficacy of the interleukin‐2 receptor antagonist basiliximab in steroid‐refractory acute graft‐versus‐host disease

Acute graft-versus-host disease (aGVHD) occurs in up to 80% of patients who undergo allogeneic stem cell transplantation (SCT) and contributes significantly to transplant-related mortality (TRM). We conducted a prospective phase II trial to assess the efficacy and feasibility of treating steroid-refractory aGVHD with basiliximab, a chimaeric monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor. Basiliximab was administered intravenously at a dose of 20 mg on days 1 and 4. Twenty-three patients were enrolled between October 1999 and July 2004. We found a primary overall response rate of 82.5% with four patients (17.5%) showing a complete response and 15 patients (65%) a partial response. Six patients were again treated successfully with an IL-2 receptor antagonist because of recurrence of aGVHD. The rates of infections, chronic GVHD, malignancy recurrence and 1-year TRM following immunosuppression with basiliximab were comparable with those found with other treatment modalities for aGVHD. We conclude that basiliximab is efficient and feasible for steroid-refractory aGVHD and merits further evaluation.

Adult Matched Sibling Blood Cell Transplants (BCT) after Myeloablative Conditioning Incorporating Daily Intravenous (IV) Busulfan (BU) and Low-Dose Antithymocyte Globulin (ATG): Outcomes with Particular Respect to Transplant-Related Mortality (TRM) in 140 Patients.

Intravenous BU allows more predictable exposure and is more convenient to administer once daily than the conventional four times daily regimen. Low-dose pretransplant ATG may reduce morbidity and mortality from graft-versus-host disease (GVHD). We have investigated a myeloablative regimen incorporating these agents in 140 adults aged 18–65 (median 47) receiving a first MRD SCT between 05/99 and 01/04. Conditioning comprised fludarabine (FLU) 50mg/m2on days −6 to −2 and IV BU (Busulfex, ESP Pharma) 3.2 mg/kg daily days −5 to −2 inclusive (FLUBUP) in 116 patients (pts) with additional TBI 200cGy x 2 in 24 (14 ALL, 8AML, 2 biphenotypic). Forty-three pts had standard-risk (SR) acute leukemia in CR1 (35 AML, 8 ALL), and 23 had active acute leukemia (HA) (18 AML±MDS, 3 ALL, 2 biphenotypic). A third group of 74 other (OTH) pts comprised 2 AML CR2, 2 ALL CR2, 2 CML (1 AP, 1CP2), 13 MDS, 11 MM, 24 NHL, 6 HD (2 with CLL), 8 CLL, 5 other. All pts were given cyclosporine A, “short course” methotrexate with folinic acid and Thymoglobulin (Genzyme) (ATG) 4.5 mg/kg in divided doses over 3 consecutive days pretransplant finishing D0. Followup of survivors is 6–61 months, median 26. Incidence of acute GVHD (aGVHD) grade II–IV was 19±4%, grade III–IV 6±2% and chronic GVHD (cGVHD) 66±5% (at 2 years). Projected TRM is 4±2% at 100 days, 10±3% at 1 year and 14±4% at 5 years. For acute leukemia pts projected TRM at one year is 5±5% vs 12±5% with (n = 24) and without (n = 47) TBI respectively (p = ns). Four non-relapse deaths occurred before day 100 one each from myocardial infarct (MI), acute GVHD, candidiasis and VOD. Ten deaths between days 102–569 were related to aGVHD in one and complications in pts with cGVHD in 9 (occurring in 1 pt after 2nd BCT for graft failure) including 1 VZV, 3 other infection, 1 PE, 1 MI. Of 11 follicular NHL pts 3 died of cGVHD and its complications after 1st BCT compared with 5 of 129 others (p = 0.02). Twelve of the transplant-related deaths were in 76 pts ≥ 46 years old compared with 2 in 64 younger pts (TRM = 23±6%, vs 4±3%, p = 0.01). Of 55 relapsed pts 17 are alive, 8 of these are in remission after more treatment and/or onset of GVHD. Projected 5-year disease-free survival and survival respectively is 46±5% and 57±5% for all pts, 62±8% and 76±7% for SR, 51±7% and 59±9% for OTH, and 9±6% and 16±8% for HA. This study indicates that: 1) regimen related mortality is low in MRD BCT recipients given this regimen 2) cGVHD is the main cause of TRM 3) pts with follicular NHL seem to be comparatively susceptible to death related to cGVHD 4) addition of 400cGy TBI does not increase risk of TRM and 5) older age remains a risk factor for TRM.