What is the outcome in patients with acute leukaemia who survive severe acute graft-versus-host disease?

BACKGROUND: Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic haematopoietic stem cell transplantation (HSCT). With new promising therapies, survival may improve for severe aGVHD. OBJECTIVES: We wanted to analyze the long-term outcome in patients who survive severe aGVHD. METHODS: This study was a landmark analysis of 23 567 patients with acute Leukaemia who survived for more than 6 months after HSCT, 2002-2014. Patients alive after severe aGVHD (n = 1738) were compared to controls. RESULTS: Patients with severe aGVHD had higher non-relapse mortality (NRM) and higher rate of extensive chronic GVHD (cGVHD) than the controls (P < 10-5 ). The probability of relapse was significantly lower in the severe aGVHD group, but Leukaemia-free survival (LFS) and overall survival were significantly lower than for the controls (P < 10-5 ). Five-year LFS in patients with severe aGVHD was 49%, as opposed to 61% in controls with no or mild GVHD and 59% in patients with moderate GVHD. CONCLUSIONS: HSCT patients who survive severe aGVHD have higher risk of developing extensive cGVHD, a higher NRM, a lower relapse probability, and lower LFS than other HSCT patients. This study is a platform for outcome analysis in patients treated with novel therapies for acute GVHD.

A prospective randomized toxicity study to compare reduced-intensity and myeloablative conditioning in patients with myeloid leukaemia undergoing allogeneic haematopoietic stem cell transplantation.

BACKGROUND: To our knowledge, no randomized toxicity studies have been conducted to compare myeloablative conditioning (MAC) and reduced-intensity conditioning (RIC) in allogeneic haematopoietic stem cell transplantation (HSCT). METHODS: Adult patients ≤60 years of age with myeloid leukaemia were randomly assigned (1 : 1) to treatment with RIC (n = 18) or MAC (n = 19) in this Phase II single-centre toxicity study. RESULTS: There was a maximum median mucositis grade of 1 in the RIC group compared with 4 in the MAC group (P < 0.001). Haemorrhagic cystitis occurred in eight of the patients in the MAC group and none in the RIC group (P < 0.01). Results of renal and hepatic tests did not differ significantly between the two groups. RIC-treated patients had faster platelet engraftment (P < 0.01) and required fewer erythrocyte and platelet transfusions (P < 0.001) and less total parenteral nutrition (TPN) than those treated with MAC (P < 0.01). Cytomegalovirus (CMV) infection was more common in the MAC group (14/19) than in the RIC group (6/18) (P = 0.02). Donor chimerism was similar in the two groups with regard to CD19 and CD33, but was delayed for CD3 in the RIC group. Five-year transplant-related mortality (TRM) was approximately 11% in both groups, and rates of relapse and survival were not significantly different. Patients in the MAC group with intermediate cytogenetic acute myeloid leukaemia had a 3-year survival of 73%, compared with 90% among those in the RIC group. CONCLUSION: Reduced-intensity conditioning had several advantages compared with MAC, including less mucositis, less haemorrhagic cystitis, faster platelet engraftment, the need for fewer transfusions and less TPN, and fewer CMV infections. Both regimens were tolerated and TRM was low.

Analysis of tissues following mesenchymal stromal cell therapy in humans indicates limited long-term engraftment and no ectopic tissue formation.

Mesenchymal stromal cells (MSCs) are explored as a novel treatment for a variety of medical conditions. Their fate after infusion is unclear, and long-term safety regarding malignant transformation and ectopic tissue formation has not been addressed in patients. We examined autopsy material from 18 patients who had received human leukocyte antigen (HLA)-mismatched MSCs, and 108 tissue samples from 15 patients were examined by PCR. No signs of ectopic tissue formation or malignant tumors of MSC-donor origin were found on macroscopic or histological examination. MSC donor DNA was detected in one or several tissues including lungs, lymph nodes, and intestine in eight patients at levels from 1/100 to <1/1,000. Detection of MSC donor DNA was negatively correlated with time from infusion to sample collection, as DNA was detected from nine of 13 MSC infusions given within 50 days before sampling but from only two of eight infusions given earlier. There was no correlation between MSC engraftment and treatment response. We conclude that MSCs appear to mediate their function through a "hit and run" mechanism. The lack of sustained engraftment limits the long-term risks of MSC therapy.

Increased risk of gastrointestinal acute GVHD following the addition of melphalan to busulfan/cyclophosphamide conditioning.

Risk factors associated with the development of aGVHD in the gastrointestinal tract have not been studied in depth. We retrospectively assessed 25 pediatric patients with MDS and JMML and compared the treatment outcome of two different conditioning regimens. Seventeen children (68%) underwent conditioning with busulfan (Bu), cyclophosphamide (Cy), and melphalan (Mel) and eight children (32%) with Bu and Cy. Gastrointestinal aGVHD stages II-IV (day 0-100) were observed in 47% (eight of 17) of the patients in the BuCyMel group and in none (0 of 8) in the BuCy group (p < 0.05). In patients who developed gastrointestinal aGVHD stages III-IV, a 24-h variation in the Bu concentration with a nighttime peak was noted. HC and liver aGVHD stages II-IV were observed in 47% (eight of 17) and 35% (six of 17) after BuCyMel conditioning and in 0% (0 of 17) and 12.5% (one of eight) after BuCy conditioning. The overall survival rate was 53% (nine of 17) in the BuCyMel group and 62.5% (five of eight) in the BuCy group. In conclusion, the addition of melphalan to the BuCy conditioning regimen resulted in severe gastrointestinal complications and did not improve overall survival.

Bone marrow or peripheral blood stem cell transplantation from unrelated donors in adult patients with acute myeloid leukaemia, an Acute Leukaemia Working Party analysis in 2262 patients.

BACKGROUND: No survival benefit of using blood stem cells instead of bone marrow (BM) has been shown in matched unrelated donor (MUD) transplantation. DESIGN AND METHODS: In a retrospective registry analysis, we compared the use of blood stem cells (n = 1502) and BM (n = 760) from unrelated donors in patients aged 18-60 years with acute myeloid leukaemia (AML) undergoing myeloablative conditioning between 1997 and 2008. The blood stem cell recipients were older (P < 0.01), had more advanced disease (P < 0.0001) and received less total body irradiation (P < 0.0001) and more antithymocyte globulin (P = 0.01). RESULTS: Recovery of neutrophils and platelets was faster with blood stem cells (P < 0.0001). The incidence of acute graft-versus-host disease (GVHD) was similar, but there was more chronic GVHD in the blood stem cell group [hazard ratio (HR) = 1.29, P = 0.02]. There were no significant differences in nonrelapse mortality (NRM), relapse incidence and leukaemia-free survival (LFS) between the two groups amongst patients with AML in remission. In patients with advanced leukaemia, NRM was lower (HR = 0.61, P = 0.02) and LFS was prolonged (HR = 0.67, P = 0.002) when blood stem cells were used. At 3 years, LFS for all patients, regardless of remission status, was 41% for both treatment groups. The outcome was not affected after multivariable analysis adjusted for confounders. CONCLUSION: Blood stem cells compared with BM in MUD transplantation for patients with AML in remission resulted in the same rates of LFS. In patients with advanced leukaemia, the blood stem cell group had reduced NRM and improved LFS.

Stromal cells from term fetal membrane are highly suppressive in allogeneic settings in vitro.

Bone marrow-derived mesenchymal stromal cells (BM-MSCs) have immunosuppressive properties and have been used to treat steroid-refractory acute graft-versus-host disease (GVHD) in stem cell transplant patients. Cells with similar capacities can also be found in term placental tissue. We have isolated stromal cells from term fetal membrane (FMSCs), umbilical cords (UCSCs) and placental villi (PVSCs) as well as from bone marrow and compared their immunoregulatory capacity in allogeneic settings. We found that FMSCs and UCSCs suppressed proliferation significantly in mixed lymphocyte reactions (MLRs), whereas PVSCs showed inconsistent suppressive effects. When added to MLR cultures, FMSCs suppressed the production of interferon (IFN)-γ and interleukin (IL)-17, whereas UCSCs and PVSCs promoted the production of IL-17 instead. Secretion of IL-10 was increased after addition of FMSCs and UCSCs. In this setting, BM-MSCs had no significant effect on secretion of IFN-γ, IL-17 or IL-10 in MLR cultures. When analysing the expression of adhesion markers, we noted that FMSCs expressed the highest levels of CD29 (ß1), CD49d (α4) and CD54 (ICAM-1) compared to the other types of stromal cells. Thus, our data indicate that stromal cells isolated from term fetal membrane have great immunosuppressive capacity in terms of proliferation and production of proinflammatory cytokines from alloreactive T cells, and also promote anti-inflammatory IL-10. They express high levels of integrins that may be of importance in homing to inflamed tissues. Fetal membrane may provide a valuable source of cells with immunosuppressive properties and could possibly be used for treatment of acute GVHD and other inflammatory disorders.

Disturbances in dental development and craniofacial growth in children treated with hematopoietic stem cell transplantation.

OBJECTIVES: To investigate the correlation between age, degree of disturbances in dental development, and vertical growth of the face in children treated with hematopoietic stem cell transplantation (HSCT). PATIENTS: 39 long-term survivors of HSCT performed in childhood and transplanted before the age of 12, at a mean age of 6.8±3.3 years. METHODS: Panoramic and cephalometric radiographs were taken at a mean age of 16.2 years. For each patient two age- and sex-matched healthy controls were included. The area of three mandibular teeth was measured and a cephalometric analysis was performed. RESULTS: The mean area of the mandibular central incisor, first and second molar was significantly smaller in the HSCT group, and the vertical growth of the face was significantly reduced, especially in the lower third, compared to healthy controls. A statistically significant correlation between age at HSCT, degree of disturbances in dental development, and vertical growth of the face was found. Children subjected to pre-HSCT chemotherapy protocols had significantly more growth reduction in vertical craniofacial variables compared to children without pre-HSCT chemotherapy. Conditioning regimens including busulfan or total body irradiation had similar deleterious effects on tooth area reduction and craniofacial parameters. CONCLUSIONS: The younger the child is at HSCT, the greater the impairment in dental and vertical facial development. This supports the suggestion that the reduction in lower facial height found in SCT children mainly is a result of impaired dental development and that young age is a risk factor for more severe disturbances.

Hematopoietic stem cell transplantation in severe congenital neutropenia.

BACKGROUND: Severe congenital neutropenia (SCN) is an immunodeficiency characterized by disturbed myelopoiesis and an absolute neutrophil count (ANC) <0.5 × 10(9)/L. SCN is also a premalignant condition; a significant proportion of patients develop myelodysplastic syndrome or leukemia (MDS/L). Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for SCN. PROCEDURE: Since 2004, eight HSCT have been performed in seven patients at our center. The indications were transformation to MDS/L (n = 2), granulocyte colony-stimulating factor receptor (CSF3R) mutation(s) (n = 2), granulocyte colony-stimulating factor (G-CSF) resistance (n = 2), and at the patient's own request (n = 1). RESULTS: The mean age at transplantation was 13 years (2.8-28 years) (mean follow-up 32 months, range 21-60). Three patients harbored ELANE mutations, three HAX1 mutations, and in one patient no causative mutation was identified. Two of the ELANE mutations were novel mutations. Three patients initially received myeloablative conditioning and four had reduced intensity conditioning (RIC). Three grafts were from HLA-identical siblings, three from matched unrelated donors and two were cord blood units. Engraftment occurred in all patients. Two of seven (29%) patients died; both had MDS/L and both were among the three that underwent myeloablative conditioning. One patient has chronic GVHD 2 years post-transplant. CONCLUSIONS: The role of HSCT should be explored further in patients with SCN. In particular, the influence of the conditioning regime needs to be evaluated in a larger cohort of patients.

Long-term salivary function after conditioning with busulfan, fractionated or single-dose TBI.

OBJECTIVES: Does conditioning with fractionated total body irradiation (fTBI) or busulfan (Bu) causes less salivary dysfunction compared with single dose (sTBI) after hematopoietic stem cell transplantation (HSCT). PATIENTS AND METHODS: A total of 74 adolescents below 13 years of age received allogeneic HSCT and conditioning with either: sTBI, fTBI or Bu. The unstimulated (USSR) and stimulated (SSSR) whole salivary secretion rates were measured at 15 years of age. RESULTS: Irrespective of conditioning type, there were no significant differences in USSR or SSSR between groups. Girls had a significantly lower SSSR, 0.7 ± 0.3 ml per min compared with 1.1 ± 0.4 ml per min in boys (P < 0.001). A significant correlation between age at HSCT and SSSR at 15 years of age (P = 0.02) in children conditioned with sTBI was found as well as an inverse correlation between the plasma area under curve (AUC) of Bu and SSSR. In the multivariate model, only female sex was significantly correlated with low SSSR at 15 years of age (OR 3.93, 95% CI 1.21-12.79; P = 0.021). CONCLUSION: No differences in long-term whole salivary function after HSCT in adolescents receiving conditioning with sTBI, fTBI or Bu were found. Total systemic exposure to Bu was negatively correlated with stimulated salivary secretion.

Optimizing in vitro conditions for immunomodulation and expansion of mesenchymal stromal cells.

BACKGROUND AIMS: Mesenchymal stromal cells (MSC) can be expanded in vitro for clinical use and have been evaluated in clinical trials as immunosuppressants and to heal damaged tissues. We investigated the impact of freezing and prolonged storage on cell viability, proliferation and immunosuppression in vitro. METHODS: MSC were expanded from bone marrow (BM) of healthy subjects according to standard protocols in the presence of fetal calf serum (FCS). The immunosuppressive potential of MSC was analyzed in mixed lymphocyte cultures (MLC) and after stimulation with phytohemagglutinin (PHA). RESULTS: Expansion of frozen mononuclear cells (MNC) diminished MSC yield after expansion compared with plating of fresh MNC. MSC derived from frozen MNC were also less immunosuppressive. MSC harvested at various passages after expansion in vivo suppressed lymphocyte proliferation equally. Pooling of MSC from several donors generated higher and more stable suppression in both MLC and after PHA stimulation. After passage 1, plating at lower densities in 20% FCS increased cell expansion of MSC up to 25-fold compared with standard conditions. CONCLUSIONS: MNC should not be frozen prior to MSC expansion. Decreased replating density and increased FCS levels generate higher numbers of MSC. Freezing of ex vivo-expanded MSC for >30 months did not affect cell viability or the ability to suppress lymphocyte proliferation. For effective immunosuppression in vitro MSC should be stored for less than 6 months and pooled from two or three donors.

A randomized study of buffy coat platelets in platelet additive solution stored 1-5 versus 6-7 days prior to prophylactic transfusion of allogeneic haematopoietic progenitor cell transplant recipients.

BACKGROUND AND OBJECTIVE: Storage of platelets > 5 days provides improved availability, logistical management and decreased outdating. Promising results on in vitro parameters and on in vivo post-transfusion recovery and survival of autologous platelets in healthy volunteers have earlier been shown. To provide additional verification, randomized patient transfusion studies are needed. MATERIALS AND METHODS: Sixty allogeneic haematopoietic progenitor cell transplant recipients were randomized to receive buffy-coat (BC) platelets stored in platelet additive solution (PAS) for 1-5 days the first time a prophylactic transfusion was needed after transplantation, followed the second time by platelets stored for 6-7 days or vice versa. The corrected count increment (CCI) for 1 and 24 h were calculated. RESULTS: CCI 1 h and CCI 24 h were higher for platelets stored 1-5 days as compared to 6-7 days, 10.4 +/- 5.1 vs. 7.4 +/- 3.8 (P < 0.001) and 5.4 +/- 4.1 vs. 2.6 +/- 2.6 (P < 0.001), respectively. Time to next platelet transfusion was significantly longer after a transfusion of platelets stored for 1-5 days as compared to platelets stored for 6-7 days: 2.2 +/- 1.1 vs. 1.6 +/- 0.8 days, respectively (P < 0.005). No differences in bleeding events and no transfusion reaction were recorded. CONCLUSION: The advantage of an extension of platelet storage time beyond day 5 should be balanced against the increased need for platelet transfusions that may occur and the conceivable risk of transfusion failure.

Targeted monitoring of patients at high risk of post-transplant lymphoproliferative disease by quantitative Epstein-Barr virus polymerase chain reaction.

BACKGROUND: Epstein-Barr virus (EBV)-associated post-transplantation lymphoproliferative disease (PTLD) is a serious complication after allogeneic stem cell transplantation (SCT). The likelihood of PTLD is increased in the presence of specific risk factors. Monitoring of EBV DNA load and early administration of rituximab in patients with high EBV loads is recommended for high-risk patients. METHODS: Patients at high risk of EBV-associated PTLD were defined as those showing an EBV serological mismatch between donor and recipient, those with lymphoma, those given cord blood grafts, and those with primary EBV disease before SCT. High-risk patients were prospectively monitored by weekly measurement of EBV DNA by quantitative polymerase chain reaction assay, and rituximab was given when the EBV load reached 10,000 copies/mL or symptoms were suggestive of EBV disease. During the study period (July 2005 to the end of June 2007) 131 patients underwent SCT, of whom 53 had high risk factors. A historical control group transplanted between January 2003 to the end of June 2005 was retrospectively used to evaluate the effect of the prospective monitoring strategy. RESULTS: Of the patients, 30% were positive for EBV DNA at least once; 10% of patients with EBV DNAemia developed PTLD. Risk factors of EBV DNAemia were younger age (P=0.04), receiving transplants from mismatched family or unrelated donors (P=0.01), and acute graft-versus-host disease grades II-IV (P=0.001). The overall frequency of PTLD was 3%; 5.7% in the high-risk group and 1.3% in the standard-risk group. Previous splenectomy (P=0.046) was the only significant risk factor associated with PTLD. In the control group, 6 of 150 patients (4%) developed PTLD; 5/53 (9.4%) in the high-risk group and 1/97 (1%) in the standard-risk group. Human leukocyte antigen-mismatched donors (P<0.01) and EBV-positive donors/EBV-negative recipients (P=0.01) had a significant impact on the risk of PTLD. CONCLUSION: A targeted monitoring strategy among patients at a high risk of EBV-associated PTLD might be helpful to decrease the risk of development of PTLD. However, larger prospective studies are needed to verify this hypothesis.

Outcome of haematopoietic stem cell transplantation in patients transplanted with matched unrelated donors vs allele-mismatched donors: a single centre study.

We studied the importance of human leucocyte antigen (HLA)-A, -B and -DRB1 high-resolution matching on the outcome of haematopoietic stem cell transplantation (HSCT) with matched unrelated donors (MUDs) vs single allele-mismatched unrelated donors. Fifty consecutive HSCT patients receiving an HLA-A, -B or -DR allele-level-mismatched unrelated graft (mmUD) were compared with a matched cohort of 100 patients with an HLA-A, -B and -DR-MUD. Rejection occurred in seven patients (14%) in the mmUD group and in four patients (4%) in the MUD group (P = 0.04), but this was mainly an effect of HLA-C mismatch. The cumulative incidence of acute graft vs host disease (GVHD) grades II-IV were 61%, 26% and 33% in the class I mmUD, class II mmUD and MUD groups, respectively. In multivariate analysis, HLA class I mismatch was associated with an increased risk of acute GVHD grades II-IV (2.09, P = 0.007) and transplant-related mortality (TRM) (1.99, P = 0.06). The 5-year overall survival was 81% in patients with a class II allele-mismatched donor compared with 52% (P = 0.025) and 50% (P = 0.017) in patients with a class I mismatch and a MUD. In multivariate analysis, HLA class II allele mismatch was associated with improved survival (3.38, P = 0.019). Relapse-free survival were 53%, 37% and 42% in patients with a class II mmUD, class I mmUD and a MUD, respectively (not significant). An HLA-C or -DQ mismatch had no significant impact on survival, TRM and relapse. In conclusion, compared with MUD, HLA class I allele mmUD had an increased risk of acute GVHD and TRM.

No increased trapping of multipotent mesenchymal stromal cells in bone marrow filters compared with other bone marrow cells.

BACKGROUND: Multipotent mesenchymal stromal cells (MSC) are candidates for cellular therapy in regenerative medicine and as treatment of graft-versus-host-disease (GvHD) after hematopoietic stem cell (HSC) transplantation. It has been suggested that MSC may be trapped in bone marrow (BM) filters during the stem cell procurement and lost from the HSC graft. METHODS: We investigated filtered BM and filters from six HSC donors. MSC were expanded from the two sources and investigated by flow cytometry, doubling capacity, differentiation ability and suppression in mixed lymphocyte cultures. RESULTS: A range of 0.3-3.4% cells was trapped in the filters. By flow cytometry, there was no difference in the proportions of different cell types between the filter-retrieved and filtered BM cells. The phenotype, immunosuppressive capacity, differentiation and growth were equal in MSC expanded from the two cell sources. DISCUSSION: Given the low number of trapped cells, filters do not appear to be a good source of MSC. When intended for clinical transplantation, MSC need to be expanded ex vivo to achieve sufficient doses for a clinical effect.

No impact of NOD2/CARD15 on outcome after SCT.

Recent studies have pointed towards an association between certain single nucleotide polymorphisms (SNPs) in the NOD2/CARD15 gene, and negative outcome of Allo-SCT. In this study, 198 patients and their corresponding donors were analyzed retrospectively for the occurrence of NOD2/CARD15 mutations to evaluate the impact on clinical results after Allo-SCT. In all, 7.6% of the patients and 11% of the donors were heterozygous for one of three SNPs 8, 12 or 13. Contrary to earlier findings, we found no significant impact on incidence of acute GVHD or TRM following Allo-SCT. These differences in results could be due to a lower mutation frequency in the studied population and/or a lower overall incidence of severe GVHD. On the basis of these findings we conclude that a consideration to NOD2/CARD15 mutation status is not pertinent when selecting a donor for Allo-SCT at our centre.

Allogeneic stem cell transplantation: low immunoglobulin levels associated with decreased survival.

The aim of this study was to evaluate the effects and kinetics of IgG levels after allogeneic stem cell transplantation (SCT). This study retrospectively examines 179 consecutive patients undergoing SCT between 1995 and 2002. Diagnoses included acute and chronic leukemia (n=136), solid tumors (n=11), other malignancies (n=16) and non-malignant diseases (n=16). Standard myeloablative conditioning was given to 146 patients, and 33 patients received reduced intensity conditioning. Serum samples for measurement of IgG levels were collected 3, 6 and 12 months after SCT, and then yearly. IgG levels increased after SCT throughout the study period. Factors that were associated with low IgG levels after SCT were acute graft-versus-host disease (GVHD), patient age < or =30 years, female donor-to-male recipient, not receiving anti-thymocyte globulin and type of GVHD prophylaxis. Compared to patients with moderately low or normal levels as measured twice during the first year after transplantation, patients with low IgG levels (<4 g/l) showed a decreased survival rate (54 vs 71%, P=0.04) and an increased incidence of transplant-related mortality (27 vs 9%, P<0.01). IgG levels generally increase after SCT. Persistent low levels of IgG are a risk factor for death after SCT.

Risk factors for acute graft-versus-host disease grades II-IV after reduced intensity conditioning allogeneic stem cell transplantation with unrelated donors: a single centre study.

We analysed factors associated with moderate to severe acute GVHD in 111 patients treated with fludarabin-based reduced intensity conditioning (RIC) and allogeneic haematopoietic stem cell transplantation (HSCT). Most patients had a haematological malignancy. Donors were 97 HLA-A, -B and -DRbeta1 identical unrelated and 14 HLA-A, -B or -DRbeta1 allele mismatched unrelated donors. In the univariate analysis, we found ten factors associated with acute GVHD. These were diagnosis (P=0.06), GVHD prophylaxis with combinations other than CsA+MTX (P=0.006), graft nucleated (P<0.001) and CD34 (P<0.001) cell-dose, bidirectional ABO mismatch (P=0.001), conditioning (P=0.002), hospital vs home-care (P=0.06), ATG dose (P<0.001), donor herpes virus serology (P=0.07) and an immunized female donor to male recipient (P=0.05). In the multivariate analysis, three factors remained significant: a high CD34 cell dose (P<0.001), low dose (4 mg/kg) ATG (P<0.001), and an immunized female donor to male recipient (P<0.01). Patients receiving a CD34 cell dose > or =17.0 x 10(6) per kg had a higher incidence of GVHD, 53.7%, compared to 22.3% in patients receiving a lower dose (P=0.002). In patients without any of these risk factors (n=70), the incidence of acute GVHD was 14.1%, while it was 38.0 and 85.0% in patients with one (n=29) or two (n=10) risk factors (P<0.001). We concluded that risk factors for acute GVHD using RIC are similar as using myeloablative conditioning.

Safe administration of oral BU twice daily during conditioning for stem cell transplantation in a paediatric population: a comparative study between the standard 4-dose and a 2-dose regimen.

We compared outcome and toxicity in two paediatric groups undergoing SCT and treated with busulphan (BU) by the oral route of administration. One group receiving the standard dose of 1 mg/kg q.i.d. for a total of 16 doses was compared with age- and disease-matched patients receiving 2 mg/kg of BU b.i.d. for a total of eight doses. Seventy-two patients from two Swedish paediatric transplantation centres were included; one centre used a standard q.i.d. administration (n=37) and the second centre used a b.i.d. administration setting (n=35). Our primary objective was to determine the incidence of veno-occlusive disease (VOD), graft-versus-host disease (GVHD), relapse frequency and transplant-related mortality in both cohorts. A total of 17 autologous and 55 allogeneic transplantations was performed for malignant (n=47) and non-malignant (n=25) diseases in the two centres during the period 1990-2005. No significant difference in the incidence of VOD, graft rejection, GVHD, relapse rate or overall survival was observed between the two centres. The clinical outcome of SCT for paediatric patients conditioned with oral BU at a dose of 2 mg/kg for eight doses is comparable to that found for children conditioned using the standard regimen given 1 mg/kg q.i.d. for 16 doses.

Unrelated donor hematopoietic cell transplantation for hemophagocytic lymphohistiocytosis.

We report outcomes after unrelated donor hematopoietic cell transplantation (HCT) for 91 patients with hemophagocytic lymphohistiocytosis (HLH) transplanted in the US in 1989-2005. Fifty-one percent were <1 year at HCT and 29% had Lansky performance scores<90%. Most (80%) were conditioned with BU, CY, and etoposide (VP16) with or without anti-thymocyte globulin. Bone marrow was the predominant graft source. Neutrophil recovery was 91% at day-42. The probabilities of grades 2-4 acute GVHD at day-100 and chronic GVHD at 5 years were 41 and 23%, respectively. The overall mortality rate was higher in patients who did not receive BU/CY/VP16-conditioning regimen (RR 1.95, P=0.035). The 5-year probability of overall survival was 53% in patients who received BU/CY/VP16 compared to 24% in those who received other regimens. In the subset of patients with known disease-specific characteristics, only one of five patients with active disease at HCT is alive. For those in clinical remission at HCT (n=46), the 5-year probability of overall survival was 49%. Early mortality rates after HCT were high, 35% at day-100. These data demonstrate that a BU/CY/VP16-conditioning regimen provides cure in approximately 50% of patients and future studies should explore strategies to lower early mortality.

A prospective randomized study using N-acetyl-L-cysteine for early liver toxicity after allogeneic hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (ASCT) and its conditioning with chemoradiotherapy often results in liver toxicity, the most severe form being veno-occlusive liver disease (VOD). N-acetyl-L-cysteine (NAC), an antioxidant glutathione precursor, may provide protection from liver toxicity. Patients with elevated bilirubin (>26 mmol/l) and/or elevated (ALT) (>1.4 microkat/l) and/or aspartate aminotransferase (AST) (>1.4 microkat/l) levels were randomized to treatment with NAC or no treatment. Among 522 transplanted patients, 160 were included in the trial. NAC was given, 100 mg/kg per day, as a 6-h i.v. infusion until normalization of bilirubin, ALT and AST values. Maximum bilirubin level was the same in patients randomized to NAC (n=72) or controls (n=88). Increase and recovery of ALT and AST were the same in patients randomized to NAC or controls. There were two patients in the NAC group who developed VOD, as compared to three of the controls. To conclude, NAC does not improve liver toxicity after ASCT.