1.
Haploidentical vs. unrelated allogeneic stem cell transplantation for acute lymphoblastic leukemia in first complete remission: on behalf of the ALWP of the EBMT
Shem-Tov, N., Peczynski, C., Labopin, M., Itala-Remes, M., Blaise, D., Labussiere-Wallet, H., Socie, G., Kroger, N., Mielke, S., Afanasyev, B., et al
Leukemia. 2019
-
-
-
Full text
-
Editor's Choice
Abstract
Unmanipulated haploidentical allogeneic stem cell transplantation (Allo-SCT) has become an attractive alternative for patients lacking HLA-matched sibling or unrelated donors. However, data of outcome in ALL is still scarce. The outcomes of 1234 adult patients with ALL in first complete remission (CR1) who underwent Allo-SCT between 2007 and 2016 were analyzed. Comparison was done between haploidentical donor (Haplo) (136 patients), matched unrelated donor (MUD 10/10) (809 patients), and mismatched unrelated donor (MMUD 9/10) (289 patients). Univariate analysis showed similar outcomes in Haplo, MUD, and MMUD, including OS, LFS, RI, NRM, AGVHD, and CGVHD. In multivariate analysis, Haplo was not associated with worse outcomes compared to MUD 10/10 and MMUD 9/10. Indeed, compared to Haplo, the hazard ratio (HR) for LFS, OS, RI, NRM, AGVHD, and CGVHD were 1.1 (p = 0.7), 0.9 (p = 0.4), 1.35 (p = 0.2), 0.7 (p = 0.2), 1.1 (p = 0.8), and 0.8 (p = 0.2) for MUD, respectively, and 1.1 (p = 0.8), 1.0 (p = 1.0), 1.2 (p = 0.3), 0.8 (p = 0.4), 1.2 (p = 0.3), and 0.9 (p = 0.6) for MMUD, respectively. In conclusion, outcomes of adult patients with ALL in CR1 receiving Haplo Allo-SCT are comparable to MUD or MMUD transplants. Haplo should be considered as a clinically relevant option for patients lacking a matched sibling donor.
PICO Summary
Population
Adult patients with acute lymphoblastic leukaemia in first complete remission (n=1234)
Intervention
Haploidentical transplantation (n=136)
Comparison
Matched unrelated donor (n=809) or Mismatched unrelated donor (n=289)
Outcome
Univariate analysis showed similar outcomes in Haplo, MUD, and MMUD, including OS, LFS, RI, NRM, AGVHD, and CGVHD. In multivariate analysis, Haplo was not associated with worse outcomes compared to MUD 10/10 and MMUD 9/10.
2.
Increased MHC matching by C4 gene compatibility in URD HSCT
Clancy, J., Ritari, J., Lobier, M., Niittyvuopio, R., Salmenniemi, U., Putkonen, M., Itala-Remes, M., Partanen, J., Koskela, S.
Biology of blood and marrow transplantation : journal of the American Society for Blood and Marrow Transplantation. 2018
Abstract
Human leukocyte antigen (HLA) matching is a prerequisite for successful allogeneic hematopoietic stem cell transplantation (HSCT) as it lowers the occurrence and severity of graft versus host disease (GvHD). However, matching a few alleles of the classical HLA genes only may not ensure matching of the entire major histocompatibility complex (MHC) region. HLA haplotype matching has been reported to be beneficial in HSCT due to the variation relevant to GvHD risk in the non-HLA region. As polymorphism in the MHC is highly population-specific, we hypothesized that donors from the Finnish registry are more likely matched at a higher level for the Finnish patients than donors from other registries. In the present study we determined 25 single nucleotide polymorphisms (SNPs) of the complement component 4 (C4) gene in the gamma block segment of MHC from 115 Finnish HSCT patients and their Finnish (n=201) and non-Finnish (n=280) donor candidates. Full matching of HLA alleles and C4 SNPs, independently or additively, occurred more likely in the Finnish - Finnish group as compared with the Finnish - non-Finnish group (P< 0.003). This was most striking in cases with HLA haplotypes typical of the Finnish population. Patients with ancestral HLA haplotypes (AH) were more likely to find a full HLA and C4 matched donor, regardless of donors' origin as compared with patients without AH (P<0.0001). Despite the clear differences at the population level, we could not find a statistical association between C4 matching and clinical outcome. The results suggest that screening C4 SNPs can be advantageous when an extended MHC matching or HLA haplotype matching in HSCT is required. This study also supports the need for small population-specific stem cell registries.
3.
Hidden genomic MHC disparity between HLA-matched sibling pairs in hematopoietic stem cell transplantation
Koskela, S., Ritari, J., Hyvarinen, K., Kwan, T., Niittyvuopio, R., Itala-Remes, M., Pastinen, T., Partanen, J.
Scientific reports. 2018;8(1):5396
Abstract
Matching classical HLA alleles between donor and recipient is an important factor in avoiding adverse immunological effects in HSCT. Siblings with no differences in HLA alleles, either due to identical-by-state or identical-by-descent status, are considered to be optimal donors. We carried out a retrospective genomic sequence and SNP analysis of 336 fully HLA-A, -B, -DRB1 matched and 14 partially HLA-matched sibling HSCT pairs to determine the level of undetected mismatching within the MHC segment as well as to map their recombination sites. The genomic sequence of 34 genes locating in the MHC region revealed allelic mismatching at 1 to 8 additional genes in partially HLA-matched pairs. Also, fully matched pairs were found to have mismatching either at HLA-DPB1 or at non-HLA region within the MHC segment. Altogether, 3.9% of fully HLA-matched HSCT pairs had large genomic mismatching in the MHC segment. Recombination sites mapped to certain restricted locations. The number of mismatched nucleotides correlated with the risk of GvHD supporting the central role of full HLA matching in HSCT. High-density genome analysis revealed that fully HLA-matched siblings may not have identical MHC segments and even single allelic mismatching at any classical HLA gene often implies larger genomic differences along MHC.
4.
Genomic prediction of relapse in recipients of allogeneic haematopoietic stem cell transplantation
Ritari, J., Hyvarinen, K., Koskela, S., Itala-Remes, M., Niittyvuopio, R., Nihtinen, A., Salmenniemi, U., Putkonen, M., Volin, L., Kwan, T., et al
Leukemia. 2018
-
-
Free full text
-
Full text
-
Editor's Choice
Abstract
Allogeneic haematopoietic stem cell transplantation currently represents the primary potentially curative treatment for cancers of the blood and bone marrow. While relapse occurs in approximately 30% of patients, few risk-modifying genetic variants have been identified. The present study evaluates the predictive potential of patient genetics on relapse risk in a genome-wide manner. We studied 151 graft recipients with HLA-matched sibling donors by sequencing the whole-exome, active immunoregulatory regions, and the full MHC region. To assess the predictive capability and contributions of SNPs and INDELs, we employed machine learning and a feature selection approach in a cross-validation framework to discover the most informative variants while controlling against overfitting. Our results show that germline genetic polymorphisms in patients entail a significant contribution to relapse risk, as judged by the predictive performance of the model (AUC = 0.72 [95% CI: 0.63-0.81]). Furthermore, the top contributing variants were predictive in two independent replication cohorts (n = 258 and n = 125) from the same population. The results can help elucidate relapse mechanisms and suggest novel therapeutic targets. A computational genomic model could provide a step toward individualized prognostic risk assessment, particularly when accompanied by other data modalities.