Improved survival with ursodeoxycholic acid prophylaxis in allogeneic stem cell transplantation: long-term follow-up of a randomized study

We report the long-term results of a prospective randomized study on the use of ursodeoxycholic acid (UDCA) for prevention of hepatic complications after allogeneic stem cell transplantation. Two hundred forty-two patients, 232 with malignant disease, were randomized to receive (n = 123) or not to receive (n = 119) UDCA from the beginning of the conditioning until 90 days post-transplantation. The results were reported after 1-year follow-up. UDCA administration reduced significantly the proportion of patients developing high serum bilirubin levels as well as the incidence of severe acute graft-versus-host disease (GVHD), liver GVHD, and intestinal GVHD. In the UDCA prophylaxis group, nonrelapse mortality (NRM) was lower and overall survival better than in the control group. After a 10-year follow-up, the difference in the survival and NRM in favor of the UDCA-treated group, seen at 1 year, was maintained (survival 48% versus 38%, P = .037; NRM 28% versus 41%, P = .01). A landmark analysis in patients surviving at 1 year post-transplantation showed no significant differences between the study groups in the long-term follow-up in chronic GVHD, relapse rate, NRM, disease-free survival, or overall survival. These long-term results continue to support the useful role of UDCA in the prevention of transplant-related complications in allogeneic transplantation.

Human herpesvirus 6 antigenaemia in allogeneic stem cell transplant recipients: impact on clinical course and association with other beta-herpesviruses

Human herpesvirus 6 (HHV-6) antigenaemia was prospectively studied in 58 adult allogeneic stem cell transplant (SCT) recipients. Altogether 42 of 58 recipients (72%) demonstrated HHV-6 specific antigens in peripheral blood mononuclear cells after SCT, 22 of 36 (61%) when the donor was a sibling and 20 of 22 (91%) when the donor was unrelated. The cumulative incidence of HHV-6A, HHV-6B, HHV-7, and cytomegalovirus antigenaemia during the first 6 months after SCT was 33%, 62%, 44% and 63% respectively. The median day of the onset of each antigenaemia was +24, +4, +59, and +46 after SCT respectively. There were no clinical findings related to HHV-6A and HHV-7 antigenaemias. A rash was diagnosed in 10 of 38 (26%) HHV-6B antigenaemia positive patients during the first month after SCT compared with one of 20 (5%) HHV-6B negative patients. Of the HHV-6B antigenaemia cases, six of 10 rashes were treated as acute graft-versus-host disease (GVHD) and four of 10 were considered to be of a viral origin. Fifteen patients had acute GVHD diagnosed. Acute GVHD manifested statistically significantly (P = 0.034) earlier in the nine patients with HHV-6B antigenaemia compared with the six patients who were HHV-6B negative.

The utility of intensified environmental surveillance for pathogenic moulds in a stem cell transplantation ward during construction work to monitor the efficacy of HEPA filtration

A 12-week environmental study was performed to ensure that the patient rooms of an SCT ward with high-efficiency particulate air (HEPA) filtration remained uncontaminated by moulds during close-by construction work. The sampling included measuring the ventilation channel pressure, particle count measurements, air sampling, settled dust analysis and fungal cultures from the oral and nasal cavities of the patients. No changes in the air pressure occurred. Median particle counts in patient rooms were 63-420 particles/l. The mean particle count of the outside air was 173,659 particles/l. Patient room air samples were negative for aspergilli in 32 of 33 cases. All samples of the outside air were positive for moulds. Aspergillus fumigatus was isolated at the beginning of excavation works at the construction area and in two of 33 dust samples from patient rooms. All 70 nasal samples were negative. Of 35 mouth samples, one sample was positive for A. niger in a patient with a previously diagnosed aspergillus infection. During a median follow-up of 214 days, no invasive aspergillus infections were diagnosed in the 55 patients treated during the construction period. In conclusion, the HEPA filters seemed to have performed well in preventing an aspergillosis outbreak.

Incidence, Risk Factors, and Long-term Outcome of Acute Leukemia Patients With Early Candidemia After Allogeneic Stem Cell Transplantation: A Study by the Acute Leukemia and Infectious Diseases Working Parties of European Society for Blood and Marrow Transplantation

Background

This study was performed to assess the incidence of and risk factors for Candida infection in the first 100 days after allogeneic hematopoietic stem cell transplantation (HSCT) and the impact on long-term survival.

Methods

We performed an outcome analysis of 28542 acute leukemia patients who underwent HSCT from 2000 to 2012. There were 347 patients with candidemia by day 100 and 28195 without candidemia or any other type of Candida infection.

Results

The incidence of candidemia by day 100 was 1.2% and occurred at a median of 22 days after HSCT. Higher 100-day nonrelapse mortality (NRM; hazards ratio [HR], 3.0, P < .0001) and lower 100-day overall survival (OS; HR, 2.5, P < .0001) were observed in patients with candidemia. The case fatality rate by day 100 in patients with candidemia was 22% (76/347). Factors associated with candidemia occurrence were female gender, bone marrow or cord blood stem cell source, T-cell depletion, use of total body irradiation, and acute graft vs host disease. Among the patients alive at day 100, the 5-year NRM and OS after a median follow-up of 5.6 years (95% confidence interval, 5.5 - 5.7) for patients with and without candidemia were 22.5% vs 13.5%, P < .0001 and 45.6% vs. 53.4%, P = .0003, respectively. In multivariate analysis, the occurrence of a candidemia episode by day 100 was an independent risk factor for higher NRM (HR, 1.7, P = .001) and lower OS (HR, 1.4, P = .001).

Conclusions

The early occurrence of candidemia after HSCT is still associated with higher NRM and lower short- and-long-term OS.

Candidaemia in allogeneic stem cell transplant recipients: low risk without fluconazole prophylaxis

Invasive fungal infections (IFI) are common in allogeneic SCT recipients. We have reviewed our experience of IFI with special reference to candidaemia in 685 adult patients transplanted in 1983-2002. The donor was a matched sibling in 505 patients and an unrelated donor in 180 patients. A BM graft was used in 561 patients and a PB graft in 124 patients. Fluconazole prophylaxis was not used during the study period. Definite or probable IFI was observed in 60 patients (8.7%) with a dominance of Aspergillus infections (46 patients, incidence 6.7%). Candidaemia was found only in nine patients (1.3%). The causative agents were Candida albicans (n=8), C. krusei (n=2), and C. glabrata (n=1); in two patients, two causative agents were found. The median time to the diagnosis of candidaemia was 53 days (range 6-249 days) post transplant. Seven patients were neutropaenic at diagnosis, and four patients had experienced acute GVHD. All patients received antifungal therapy, but only one patient was cured. According to this study, candidaemia was a rare event in allogeneic SCT recipients. Thus, systematic prophylaxis against Candida infections might not be indicated. The prognosis of established infections is still poor due to comorbid conditions, notably GVHD.

Genetic polymorphism related to monocyte-macrophage function is associated with graft-versus-host disease

Despite detailed human leukocyte antigen (HLA) matching and modern immunosuppressive therapy, severe graft-versus-host disease (GvHD) remains a major hurdle for successful allogeneic hematopoietic stem cell transplantation (HSCT). As the genetic diversity in GvHD complicates the systematic discovery of associated variants across populations, we studied 122 GvHD-associated single nucleotide polymorphisms (SNPs) in 492 HLA-matched sibling HSCT donor-recipient pairs from Finland and Spain. The association between these candidate SNPs and grade III–IV acute GvHD and extensive chronic GvHD was assessed. The functional effects of the variants were determined using expression and cytokine quantitative trait loci (QTL) database analyses. Clear heterogeneity was observed in the associated markers between the two populations. Interestingly, the majority of markers, such as those annotated to IL1, IL23R, TLR9, TNF, and NOD2 genes, are related to the immunological response by monocytes-macrophages to microbes, a step that precedes GvHD as a result of intestinal lesions. Furthermore, cytokine QTL analysis showed that the GvHD-associated markers regulate IL1β, IFNγ, and IL6 responses. These results support a crucial role for the anti-microbial response in GvHD risk. Furthermore, despite apparent heterogeneity in the genetic markers associated with GvHD, it was possible to identify a biological pathway shared by most markers in both populations.

Long term impact of hyperleukocytosis in newly diagnosed acute myeloid leukemia patients undergoing allogeneic stem cell transplantation: An analysis from the acute leukemia working party of the EBMT

Up to 20% of acute myeloid leukemia (AML) patients present initially with hyperleukocytosis, placing them at increased risk for early mortality during induction. Yet, it is unknown whether hyperleukocytosis still retains prognostic value for AML patients undergoing hematopoietic stem cell transplantation (HSCT). Furthermore, it is unknown whether hyperleukocytosis holds prognostic significance when modern molecular markers such as FLT3-ITD and NPM1 are accounted for. To determine whether hyperleukocytosis is an independent prognostic factor influencing outcome in transplanted AML patients we performed a retrospective analysis using the registry of the acute leukemia working party of the European Society of Blood and Marrow Transplantation. A cohort of 357 patients with hyperleukocytosis (159 patients with white blood count [WBC] 50 K-100 K, 198 patients with WBC ≥ 100 K) was compared to 918 patients without hyperleukocytosis. Patients with hyperleukocytosis were younger, had an increased rate of favorable risk cytogenetics, and more likely to be FLT3 and NPM1 mutated. In multivariate analysis, hyperleukocytosis was independently associated with increased relapse incidence (hazard ratio [HR] of 1.55, 95% confidence interval [CI], 1.14-2.12; P = .004), decreased leukemia-free survival (HR of 1.38, 95% CI, 1.07-1.78; P = .013), and inferior overall survival (HR of 1.4, 95% CI, 1.07-1.84; P = .013). Hyperleukocytosis retains a significant prognostic role for AML patients undergoing HSCT.

Clinical characteristics, outcome and the role of viral load in nontransplant patients with Epstein-Barr viraemia

Epstein-Barr virus (EBV) is important in the development of post-transplant lymphoproliferative disease in allogeneic stem cell and solid organ transplant recipients. We have studied the clinical significance of EBV DNAaemia among nontransplant patients in a tertiary referral hospital. We retrospectively reviewed the medical records for main diagnosis, outcome, immunosuppressive/cytotoxic chemotherapy and other opportunistic infections of the patients who were found positive in quantitative real-time PCR assay for EBV (EBV-qPCR) between the years 2000 and 2007. Allogeneic stem cell and solid organ transplant recipients were excluded, and all patients in nonsurgical adult wards were included. Altogether, 62 patients had at least one plasma sample positive with an EBV-qPCR. Fifteen were immunocompetent, most had primary EBV infection, and the outcome was good. On the other hand, 36 had malignant disease, seven had HIV infection and seven had immunosuppressive conditions of an other aetiology. All but one of the malignancies were of lymphoid origin, and most of these patients had a history of multiple cytotoxic treatments. Immunosuppressed patients had higher viral loads. EBV viraemia is associated with severe immunosuppression and lymphoid malignancies.

Computational Analysis of HLA-presentation of Non-synonymous Recipient Mismatches Indicates Effect on the Risk of Chronic Graft-vs.-Host Disease After Allogeneic HSCT

Genetic mismatches in protein coding genes between allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipient and donor can elicit an alloimmunity response via peptides presented by the recipient HLA receptors as minor histocompatibility antigens (mHAs). While the impact of individual mHAs on allo-HSCT outcome such as graft-vs.-host and graft-vs.-leukemia effects has been demonstrated, it is likely that established mHAs constitute only a small fraction of all immunogenic non-synonymous variants. In the present study, we have analyzed the genetic mismatching in 157 exome-sequenced sibling allo-HSCT pairs to evaluate the significance of polymorphic HLA class I associated peptides on clinical outcome. We applied computational mismatch estimation approaches based on experimentally verified HLA ligands available in public repositories, published mHAs, and predicted HLA-peptide affinites, and analyzed their associations with chronic graft-vs.-host disease (cGvHD) grades. We found that higher estimated recipient mismatching consistently increased the risk of severe cGvHD, suggesting that HLA-presented mismatching influences the likelihood of long-term complications in the patient. Furthermore, computational approaches focusing on estimation of HLA-presentation instead of all non-synonymous mismatches indiscriminately may be beneficial for analysis sensitivity and could help identify novel mHAs.

Meta-Analysis of Genome-Wide Association and Gene Expression Studies Implicates Donor T Cell Function and Cytokine Pathways in Acute GvHD

Graft-vs.-host disease (GvHD) is a major complication after allogeneic hematopoietic stem cell transplantation that causes mortality and severe morbidity. Genetic disparities in human leukocyte antigens between the recipient and donor are known contributors to the risk of the disease. However, the overall impact of genetic component is complex, and consistent findings across different populations and studies remain sparse. To gain a comprehensive understanding of the genes responsible for GvHD, we combined genome-wide association studies (GWAS) from two distinct populations with previously published gene expression studies on GvHD in a single gene-level meta-analysis. We hypothesized that genes driving GvHD should be associated in both data modalities and therefore could be detected more readily through their combined effects in the integrated analysis rather than in separate analyses. The meta-analysis yielded a total of 51 acute GvHD-associated genes (false detection rate [FDR] <0.1). In support of our hypothesis, this number was significantly higher than that in a permutation meta-analysis involving the whole data set, as well as in separate meta-analyses on the GWAS and gene expression data sets. The genes indicated by the meta-analysis were significantly enriched in 277 Gene Ontology terms (FDR < 0.05), such as T cell function and cytokine-mediated signaling pathways, and the results highlighted several established immune mediators, such as interleukins and JAK-STAT signaling, and presented TRAF6 and TERT as potential effector candidates. Altogether, the results support the chosen methodological approach, implicate a role of gene-level variation in donors' key immunological regulators predisposing patients to acute GVHD, and present potential targets for therapeutic intervention.

Long-term outcome after allogeneic stem cell transplantation in multiple myeloma

The role of allogeneic hematopoietic stem cell transplantation (allo-SCT) in multiple myeloma is controversial. We analyzed the results of 205 patients transplanted in one center during 2000-2017. Transplantation was performed on 75 patients without a previous autologous SCT (upfront-allo), on 74 as tandem transplant (auto-allo), and on 56 patients after relapse. Median overall survival (OS) was 9.9 years for upfront-allo, 11.2 years for auto-allo, and 3.9 years for the relapse group (p = 0.015). Progression-free survival (PFS) was 2.4, 2.4, and 0.9 years, respectively (p < 0.001). Non-relapse mortality at 5 years was 8% overall, with no significant difference between the groups. Post-relapse survival was 4.1 years for upfront-allo and auto-allo, and 2.6 years for the relapse group (p = 0.066). Survival of high-risk patients was reduced. In multivariate analysis, the auto-allo group had improved OS and chronic graft-versus-host disease was advantageous in terms of PFS, OS, and relapse incidence. Late relapses occurred in all groups. Allo-SCT resulted in long-term survival in a small subgroup of patients. Our results indicate that auto-allo-SCT is feasible and could be considered for younger patients in the upfront setting.

Deep Immune Profiling of Multiple Myeloma at Diagnosis and under Lenalidomide Maintenance Therapy

The bone marrow microenvironment interacts with malignant cells and regulates cancer survival and immune evasion in multiple myeloma (MM). We investigated the immune profiles of longitudinal bone marrow samples from patients with newly diagnosed MM (n = 18) using cytometry by time-of-flight. The results before and during treatment were compared between patients with good (GR, n = 11) and bad (BR, n = 7) responses to lenalidomide/bortezomib/dexamethasone-based treatment. Before treatment, the GR group had a lower tumor cell burden and a higher number of T cells with a phenotype shifted toward CD8+ T cells expressing markers attributed to cytotoxicity (CD45RA and CD57), a higher abundance of CD8+ terminal effector cells, and a lower abundance of CD8+ naïve T cells. On natural killer (NK) cells, increased expression of CD56 (NCAM), CD57, and CD16 was seen at baseline in the GR group, indicating their maturation and cytotoxic potential. During lenalidomide-based treatment, the GR patients showed an increase in effector memory CD4+ and CD8+ T-cell subsets. These findings support distinct immune patterns in different clinical contexts, suggesting that deep immune profiling could be used for treatment guidance and warrants further exploration.