Quality control and assurance in hematopoietic stem cell transplantation data registries in Japan and other countries

Trends in allogeneic hematopoietic cell transplantation survival using population-based descriptive epidemiology method: analysis of national transplant registry data

Prognosis for patients undergoing hematopoietic cell transplantation (HCT) has been improving. Short-term survival information, such as crude survival rates that consider deaths immediately after the transplantation, may not be sufficiently useful for assessing long-term survival. Using the data of the Japanese HCT registry, the net survival rate of patients who survived for a given period was determined according to age, disease, and type of transplant. We included a total of 41,716 patients who received their first allogeneic hematopoietic cell transplantation between 1991 and 2015. For each disease, age group, graft source subcategory, net survival was calculated using the Pohar-Perme method, and 5-year conditional net survival (CS) was calculated. Ten-year net survivals of total patient cohort were 41.5% and 47.4% for males and females, respectively. Except for myelodysplastic syndrome, multiple myeloma, and adult T-cell leukemia/lymphoma, 5-year CS for 5-year transplant survivors exceeded 90%. CS was especially high for aplastic anemia, of which was over 100% for children and younger adults receiving cord blood, suggesting that these patients have similar longevity to an equivalent group from the general population. These findings provide useful information for long-term survival, and can serve as benchmark for comparisons among registries, including other cancers.

Surfing the Big Data Wave: Omics Data Challenges in Transplantation

In both research and care, patients, caregivers, and researchers are facing a leap forward in the quantity of data that are available for analysis and interpretation, marking the daunting "big data era." In the biomedical field, this quantitative shift refers mostly to the -omics that permit measuring and analyzing biological features of the same type as a whole. Omics studies have greatly impacted transplantation research and highlighted their potential to better understand transplant outcomes. Some studies have emphasized the contribution of omics in developing personalized therapies to avoid graft loss. However, integrating omics data remains challenging in terms of analytical processes. These data come from multiple sources. Consequently, they may contain biases and systematic errors that can be mistaken for relevant biological information. Normalization methods and batch effects have been developed to tackle issues related to data quality and homogeneity. In addition, imputation methods handle data missingness. Importantly, the transplantation field represents a unique analytical context as the biological statistical unit is the donor-recipient pair, which brings additional complexity to the omics analyses. Strategies such as combined risk scores between 2 genomes taking into account genetic ancestry are emerging to better understand graft mechanisms and refine biological interpretations. The future omics will be based on integrative biology, considering the analysis of the system as a whole and no longer the study of a single characteristic. In this review, we summarize omics studies advances in transplantation and address the most challenging analytical issues regarding these approaches.

Use of unapproved or off-label drugs in Japan for the treatment of graft-versus-host disease and post-transplant viral infection

Many drugs are used for unapproved indications in Japan for post hematopoietic stem cell transplant (HCT) complications. To investigate unapproved or off-label drug usage for graft-versus-host disease (GVHD) and virus infections after allogeneic HCT, we analyzed the data of Japanese HCT registry. Between 2006 and 2017, 39,941 adults and children received HCT for a variety of disease and their transplant data were captured in the registry. Among them, 14,687 and 8914 patients receiving treatment for acute and/or chronic GVHD, 24,828 patients with cytomegalovirus (CMV) infection or receiving therapies for CMV, and 4943 who received treatment for other viral infections were included in the analyses of off-label or unapproved drugs. For GVHD, mycophenolate mofetil was the most frequently used off-label drug, followed by beclomethasone, infliximab, and etanercept. For viral infections other than CMV, foscarnet was the most frequently used off-label drug. Cidofovir, which is not approved for use in Japan, was mainly used for adenovirus infection. This study demonstrated that numerous off-label and unapproved drugs have been used as key drugs for GVHD and post-transplant viral infection, and the real world date in the transplant registry may serve as an important asset to regulatory purposes.

Impact of High-Frequency HLA Haplotypes on Clinical Cytomegalovirus Reactivation in Allogeneic Hematopoietic Stem Cell Transplantation

Some studies support the hypothesis that HLA genes and haplotypes evolved by natural selection through their protective abilities against specific infectious pathogens. However, very little is known regarding the impact of high-frequency HLA haplotypes on the risk of relevant infectious diseases among a given ethnic group. We evaluated the impact of high-frequency HLA haplotypes on cytomegalovirus (CMV) reactivation and infection in allogeneic hematopoietic stem cell transplantation (allo-HSCT) in a Japanese population as a model of infectious disease that has coexisted with humans. A total of 21,127 donor-patient pairs were analyzed. HLA-A-B-DRB1 haplotypes were estimated using the maximum probability algorithm. Seven haplotypes with >1% frequency were defined as high-frequency haplotypes (HfHPs). Homozygotes of HfHP and heterozygotes had significantly lower risk of CMV reactivation and infection (hazard ratio [HR] = 0.88, P = .009 and HR = 0.93, P = .003, respectively) than homozygotes of low-frequency HLA haplotypes (LfHPs). In subgroup analyses of a different donor source, these associations were statistically significant in unrelated donor transplants. Finally, CMV risk for homozygotes and heterozygotes of each HfHP was compared with that of homozygotes of LfHPs. The 2 most predominant HfHP groups (A*24:02-B*52:01-DRB1*15:02 group and A*24:02-B*07:02-DRB1*01:01 group) had a significantly lower risk of CMV reactivation and infection (HR = 0.86, P < .001 and HR = 0.91, P = .033, respectively). Our findings suggest that HfHPs may be protective against CMV reactivation and infection and that increased care regarding CMV reactivation and infection may be necessary for patients with LfHP after allo-HSCT.

Data quality audit of a clinical quality registry: a generic framework and case study of the Australian and New Zealand Hip Fracture Registry

Objectives

The value of a clinical quality registry is contingent on the quality of its data. This study aims to pilot methodology for data quality audits of the Australian and New Zealand Hip Fracture Registry, a clinical quality registry of hip fracture clinical care and secondary fracture prevention.

Methods

A data quality audit was performed by independently replicating the data collection and entry process for 163 randomly selected patient records from three contributing hospitals, and then comparing the replicated data set to the registry data set. Data agreement, as a proxy indicator of data accuracy, and data completeness were assessed.

Results

An overall data agreement of 82.3% and overall data completeness of 95.6% were found, reflecting a moderate level of data accuracy and a very high level of data completeness. Half of all data disagreements were caused by information discrepancies, a quarter by missing discrepancies and a quarter by time, date and number discrepancies. Transcription discrepancies only accounted for 1 in every 50 data disagreements. The sources of inaccurate and incomplete data have been identified with the intention of implementing data quality improvement.

Conclusions

Regular audits of data abstraction are necessary to improve data quality, assure data validity and reliability and guarantee the integrity and credibility of registry outputs. A generic framework and model for data quality audits of clinical quality registries is proposed, consisting of a three-step data abstraction audit, registry coverage audit and four-step data quality improvement process. Factors to consider for data abstraction audits include: central, remote or local implementation; single-stage or multistage random sampling; absolute, proportional, combination or alternative sample size calculation; data quality indicators; regular or ad hoc frequency; and qualitative assessment.

Impact of Synchronous Multiple Primary Malignant Tumors on Newly Diagnosed Hematological Malignancies

BACKGROUND

Hematological malignancies are occasionally observed with synchronous multiple primary malignant tumors (sMPMTs) at diagnosis. We aimed to clarify the impact of sMPMTs on newly diagnosed hematological malignancies and determine the optimal treatment strategies.

PATIENTS AND METHODS

We analyzed the outcomes of 649 patients with hematological malignancies, including 19 patients with sMPMTs (2.9%), and compared the outcomes between patients with and without sMPMTs.

RESULTS

The overall survival (OS) and disease-free survival (DFS) rates for patients with sMPMTs were 77% and 70%, respectively, at 2 years; these rates were not statistically different from those for patients without sMPMTs (P = .17 and P = .64, respectively). Multivariate analysis showed that the presence of sMPMTs was not a significant prognostic factor for OS, DFS, or relapse (hazard ratio [HR] 1.48, 95% confidence interval [CI] 0.65-3.38, P = .35; HR 0.97, 95% CI 0.46-2.10, P = .97; and HR 0.79, 95% CI 0.29-2.14, P = .65). In patients with sMPMTs, the order of treatment was not a significant prognostic factor. However, discontinuation of treatment was a marginally favorable factor and might reflect a selection bias.

CONCLUSION

The presence of sMPMTs was not a significant risk factor for patients with newly diagnosed hematological malignancies. It is important to provide adequate treatment for both hematological malignancies and solid tumors at the physician's discretion.

Current concepts on hematopoietic stem cell transplantation outcome registries; Emphases on resource requirements for new registries

There is tremendous variability in size, scope, and resource requirements for registries depending on the number of patients and participating sites. The outcome registries are organized systems to collect uniform data using an observational study methodology. Patient registries are used to determine specified outcomes for a population for predetermined scientific, clinical, or policy purposes. Historically, outcome registries established in the development of hematopoietic stem cell transplantation (HSCT) have now evolved into myriads of locoregional and international transplant activity and outcome resources. Over time, these registries have contributed immensely in determining trends, patterns, and treatment outcomes in HSCT. There is wider variation in the goals, mission, objectives, and outcomes of the ongoing registries depending on the organizational structure. There is a growing trend toward overarching relationship of these registries to serve as complementary and interoperable resources for high potential collaborative research. In addition to capacity building, standardized, accredited, and optimally operational registries can provide unmatched and unparalleled research data that cannot be obtained otherwise. Moving forward, HSCT data collection, collation, and interpretation should be an integral part of the treatment rather than an option. Quality assurance and continuous quality improvement of the data are pivotal for credibility, measurable/quantifiable outcomes, clinically significant impact, and setting new benchmarks.

Haploidentical and Matched Sibling Donor Hematopoietic Cell Transplantation for Patients with HLA-Homozygous Haplotypes

More than 1% of the Japanese population has HLA-homozygous haplotypes. For patients with such haplotypes, HLA-haploidentical family members who have no HLA mismatch in the graft-versus-host direction are readily available donor candidates for hematopoietic cell transplantation (HCT). In this study, the outcomes of patients with homozygous HLA-A, -B, and -DRB1 antigens who received HCT without T cell depletion from a haploidentical related donor with mismatches in the host-versus-graft direction only (hetero-to-homo, n = 78) or from an HLA-matched sibling donor (MSD) (MSD-homo, n = 153) were compared with those in patients with heterozygous haplotypes who received HCT from an MSD (MSD-hetero, n = 7242). Transplant outcomes in the hetero-to-homo group were similar to those in the MSD-hetero group regarding neutrophil engraftment, grades III to IV acute graft-versus-host disease (aGVHD), nonrelapse mortality (NRM), relapse, and overall survival. On the other hand, the incidences of severe aGVHD and NRM in the MSD-homo group were significantly lower than those in the MSD-hetero group (grades III to IV aGVHD: aHR .50, P = .034; NRM: aHR .48, P = .004). In conclusion, patients with HLA-homozygous haplotypes achieved lower GVHD and NRM rates for MSD transplantation than those with HLA-heterozygous haplotypes. When an MSD or an appropriate alternative donor is not available for patients with HLA-homozygous haplotypes who need immediate transplantation, transplantation from a haploidentical donor without T cell depletion is a viable option, given the comparable transplant outcomes for hetero-to-homo HCT and MSD-hetero HCT.

A Comparison of Outcomes for Cord Blood Transplantation and Unrelated Bone Marrow Transplantation in Adult Aplastic Anemia

Earlier reports suggested that umbilical cord blood transplantation (UCBT) for aplastic anemia (AA) was feasible in alternative transplantation. To identify differences in outcomes of UCBT and HLA-matched or mismatched unrelated bone marrow transplantation (UBMT) in adults with AA, we analyzed registry data of the Japan Society for Hematopoietic Cell Transplantation and compared results of UCBT (n = 69) to 8/8-matched (n = 101), 7/8-matched (n = 65), or 6/8-matched (n = 37) UBMT. The transplantation period was from 2002 to 2012, and patients 16 years or older with AA were eligible. Median ages were 49, 35, 28, and 30 years for UCBT, 8/8-matched, 7/8-matched, and 6/8-matched UBMT, respectively. In multivariate analysis, risk of mortality was lower for 8/8-matched UBMT compared with that of UCBT (hazard ratio [HR], .55; 95% confidence interval [CI], .32 to .94; P = .029), adjusted for age and graft-versus-host disease (GVHD) prophylaxis, which were other associated factors. Mortality risks of 7/8-matched UBMT (HR, .55; 95% CI, .29 to 1.02) or 6/8-matched UBMT (HR, .67; 95% CI, .32 to 1.39) were not significantly different from those of UCBT. Risks of grade 3 or 4 acute and chronic GVHD were not different among the 4 groups. The most prevalent cause of death was graft failure in UCBT and 6/8-matched UBMT and infection in 8/8-matched and 7/8-matched UBMT. Under 40 years old,survival of UCBT was similar to that of UBMT (76%, 79%, 83%, and 83% for UCBT and 8/8-matched, 7/8-matched, and 6/8-matched UBMT, respectively, at 3 years), adjusted for transplantation period, which was another associated factor; however, for ages over 40 years, that of UCBT tended to be lower (47%, 64%, 64%, and 75% for UCBT, 8/8-matched, 7/8-matched, and 6/8-matched UBMT, respectively, at 3 years). To conclude, these data suggest that UCBT could be an alternative treatment option for younger adults when matched sibling or adequate UBMT donors are not available.