Bioprinting for the Biologist.

Building tissues from scratch to explore entirely new cell configurations could revolutionize fundamental understanding in biology. Bioprinting is an emerging technology to do this. Although typically applied to engineer tissues for therapeutic tissue repair or drug screening, there are many opportunities for bioprinting within biology, such as for exploring cellular crosstalk or cellular morphogenesis. The overall goals of this Primer are to provide an overview of bioprinting with the biologist in mind, outline the steps in extrusion bioprinting (the most widely used and accessible technology), and discuss alternative bioprinting technologies and future opportunities for bioprinting in biology.

Corticosteroids as graft-versus-host disease prophylaxis for allogeneic hematopoietic cell transplant recipients with calcineurin inhibitor intolerance.

BACKGROUND AIMS: Although calcineurin inhibitors (CNIs) have a well-established role in the prevention of graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT), their use can be limited by significant toxicities, which may result in premature treatment discontinuation. The optimal management of patients with CNI intolerance is unknown. The objective of this study was to determine the effectiveness of corticosteroids as GVHD prophylaxis for patients with CNI intolerance. METHODS: This retrospective single-center study included consecutive adult patients with hematologic malignancies who underwent myeloablative peripheral blood allogeneic HCT with anti-thymocyte globulin, CNI, and methotrexate GVHD prophylaxis in Alberta, Canada. Multivariable competing-risks regression was used to compare cumulative incidences of GVHD, relapse, and non-relapse mortality between recipients of corticosteroid versus continuous CNI prophylaxis, and multivariable Cox proportional hazards regression was applied to compare overall survival, relapse-free survival (RFS) and moderate-to-severe chronic GVHD and RFS. RESULTS: Among 509 allogeneic HCT recipients, 58 (11%) patients developed CNI intolerance and were switched to corticosteroid prophylaxis at median 28 days (range 1-53) after HCT. Compared with patients who received continuous CNI prophylaxis, recipients of corticosteroid prophylaxis had significantly greater cumulative incidences of grade 2-4 acute GVHD (subhazard ratio [SHR] 1.74, 95% confidence interval [CI] 1.08-2.80, P = 0.024), grade 3-4 acute GVHD (SHR 3.22, 95% CI 1.55-6.72, P = 0.002), and GVHD-related non-relapse mortality (SHR 3.07, 95% CI 1.54-6.12, P = 0.001). There were no significant differences in moderate-to-severe chronic GVHD (SHR 0.84, 95% CI 0.43-1.63, P = 0.60) or relapse (SHR 0.92, 95% CI 0.53-1.62, P = 0.78), but corticosteroid prophylaxis was associated with significantly inferior overall survival (hazard ratio [HR] 1.77, 95% CI 1.20-2.61, P = 0.004), RFS (HR 1.54, 95% CI 1.06-2.25, P = 0.024), and chronic GVHD and RFS (HR 1.46, 95% CI 1.04-2.05, P = 0.029). CONCLUSIONS: Allogeneic HCT recipients with CNI intolerance are at increased risks of acute GVHD and poor outcomes despite institution of corticosteroid prophylaxis following premature CNI discontinuation. Alternative GVHD prophylaxis strategies are needed for this high-risk population.

Donor Genetic Predisposition to High Interleukin-10 Production Appears Protective against Acute Graft-Versus-Host Disease.

The persistence of graft-versus-host disease (GVHD) as the principal complication of allogeneic hematopoietic cell transplantation (HCT) demonstrates that HLA matching alone is insufficient to prevent alloreactivity. We performed molecular and functional characterization of 22 candidate cytokine genes for their potential to improve matching in 315 myeloablative, 10/10 HLA-matched donor−recipient pairs. Recipients of a graft carrying the -1082GG IL10 gene promoter region variant had a three-fold lower incidence of grade II−IV acute GVHD compared to IL10-1082AA graft recipients (SHR = 0.25, p = 0.005). This was most evident in matched unrelated donor (MUD) transplants, where the greatest alloreactivity is expected. IL10-1082GG transplants did not experience an increased incidence of relapse, and, consequently, overall survival was two-fold higher in IL10-1082GG MUD transplants (HR = 0.17, p = 0.023). Longitudinal post-transplant measurements demonstrated that -1082GG is a high-IL10-producing and -expressing genotype with attenuated CD8+ T-cell reconstitution. High post-transplant donor chimerism in T- and myeloid-cells (>95%) confirmed a predominant donor, rather than recipient, genotype effect on immune function and aGVHD. To date, this is the first study to report corroborating genome-to-cellular evidence for a non-HLA donor immunogenetic variant that appears to be protective against GVHD. The incorporation of IL10 variants in donor selection criteria and clinical-management decisions has the potential to improve patient outcomes.

A biomarker-guided, prospective, phase 2 trial of pre-emptive graft-versus-host disease therapy using anti-thymocyte globulin.

BACKGROUND AIMS: Intensified immunosuppressive prophylaxis for graft-versus-host disease (GVHD) may be toxic and therefore warranted only in patients at high risk of developing GVHD. In patients who underwent allogeneic hematopoietic cell transplant at the authors' center, high serum soluble IL-2 receptor alpha (sIL-2Rα) and low IL-15 levels on day 7 post-transplant were found to predict a high risk of developing clinically significant GVHD (sGVHD), defined as grade 2-4 acute GVHD or moderate to severe chronic GVHD. METHODS: This was a prospective, phase 2 trial in which high-risk patients (serum sIL-2Rα >4500 ng/L or IL-15 <31 ng/L) received rabbit anti-thymocyte globulin (ATG) 3 mg/kg on day 8 post-transplant. Controls consisted of patients who had their sIL-2Rα/IL-15 levels measured but did not participate in the trial. A total of 68 trial patients and 143 controls were accrued to this study. The primary endpoint was incidence of sGVHD. RESULTS: There was a reduction in sGVHD in high-risk trial patients (received day 8 ATG) compared with high-risk controls (did not receive day 8 ATG) (sub-hazard ratio [SHR] = 0.48, P < 0.05). There was no significant difference between the groups in overall survival or relapse; however, there was a greater incidence of non-GVHD-associated non-relapse mortality in high-risk trial patients (SHR = 3.73, P < 0.05), mostly related to infections. This may be due in part to the biomarkers ineffectively stratifying GVHD risk. CONCLUSIONS: Pre-emptive ATG therapy is both feasible and effective at reducing sGVHD without increasing relapse. Further mitigation strategies are needed to reduce the risk of infection associated with intensified GVHD prophylaxis. This study was registered at ClinicalTrials.gov (NCT01994824).

A Phase 3 Randomized Study of Remestemcel-L versus Placebo Added to Second-Line Therapy in Patients with Steroid-Refractory Acute Graft-versus-Host Disease.

Uncontrolled studies have suggested that bone marrow-derived mesenchymal stem cells (MSCs) may be effective against acute graft-versus-host disease (aGVHD). We conducted a multicenter, randomized study to assess the efficacy of using ex vivo cultured adult human MSC (remestemcel-L) in addition to second-line therapy to treat steroid-refractory aGVHD (NCT00366145). In total, 260 patients, 6 months to 70 years of age, were enrolled from August 2006 to May 2009 and were randomized 2:1 to receive 8 intravenous infusions of remestemcel-L or placebo, given over 4 weeks, in addition to second-line therapy according to institutional standards. Four additional infusions over 4 weeks were indicated for patients with incomplete response at day 28. Randomization was stratified by aGVHD grade. Efficacy and safety were assessed through 180 days of follow-up, with the primary endpoint being durable complete response (DCR), defined as complete resolution of aGVHD symptoms for any period of at least 28 days after beginning treatment. Remestemcel-L did not meet the primary endpoint of greater DCR in the intent-to-treat population (35% versus 30%; P = 0.42). In post hoc analyses, patients with liver involvement who received at least 1 infusion of remestemcel-L had a higher DCR, and higher overall complete or partial response rate (OR) than those who received placebo (29% versus 5%; P = .047). Among high-risk patients (aGVHD grades C and D), remestemcel-L demonstrated significantly higher OR at day 28 than placebo (58% versus 37%; P = 0.03). Furthermore, pediatric patients had a higher OR with MSCs compared with placebo (64% versus 23%; P = .05). Similar rates of adverse events were observed between treatment groups. Remestemcel-L was safe and well tolerated. Results of this study did not demonstrate superior DCR compared with placebo when added to standard of care. The favorable clinical responses seen in some patient subsets may warrant further investigation.

Risk Factors for Graft-versus-Host Disease in Haploidentical Hematopoietic Cell Transplantation Using Post-Transplant Cyclophosphamide.

Post-transplant cyclophosphamide (PTCy) has significantly increased the successful use of haploidentical donors with a relatively low incidence of graft-versus-host disease (GVHD). Given its increasing use, we sought to determine risk factors for GVHD after haploidentical hematopoietic cell transplantation (haplo-HCT) using PTCy. Data from the Center for International Blood and Marrow Transplant Research on adult patients with acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who underwent PTCy-based haplo-HCT (2013 to 2016) were analyzed and categorized into 4 groups based on myeloablative (MA) or reduced-intensity conditioning (RIC) and bone marrow (BM) or peripheral blood (PB) graft source. In total, 646 patients were identified (MA-BM = 79, MA-PB = 183, RIC-BM = 192, RIC-PB = 192). The incidence of grade 2 to 4 acute GVHD at 6 months was highest in MA-PB (44%), followed by RIC-PB (36%), MA-BM (36%), and RIC-BM (30%) (P = .002). The incidence of chronic GVHD at 1 year was 40%, 34%, 24%, and 20%, respectively (P < .001). In multivariable analysis, there was no impact of stem cell source or conditioning regimen on grade 2 to 4 acute GVHD; however, older donor age (30 to 49 versus <29 years) was significantly associated with higher rates of grade 2 to 4 acute GVHD (hazard ratio [HR], 1.53; 95% confidence interval [CI], 1.11 to 2.12; P = .01). In contrast, PB compared to BM as a stem cell source was a significant risk factor for the development of chronic GVHD (HR, 1.70; 95% CI, 1.11 to 2.62; P = .01) in the RIC setting. There were no differences in relapse or overall survival between groups. Donor age and graft source are risk factors for acute and chronic GVHD, respectively, after PTCy-based haplo-HCT. Our results indicate that in RIC haplo-HCT, the risk of chronic GVHD is higher with PB stem cells, without any difference in relapse or overall survival.

Maintenance Tyrosine Kinase Inhibitors Following Allogeneic Hematopoietic Stem Cell Transplantation for Chronic Myelogenous Leukemia: A Center for International Blood and Marrow Transplant Research Study.

It remains unknown whether the administration of tyrosine kinase inhibitors (TKIs) targeting BCR-ABL1 after allogeneic hematopoietic cell transplantation (HCT) is associated with improved outcomes for patients with chronic myelogenous leukemia (CML). In this registry study, we analyzed clinical outcomes of 390 adult patients with CML who underwent transplantation between 2007 and 2014 and received maintenance TKI following HCT (n = 89) compared with no TKI maintenance (n = 301), as reported to the Center for International Blood and Marrow Transplant Research. All patients received TKI therapy before HCT. The majority of patients had a disease status of first chronic phase at HCT (n = 240; 62%). The study was conducted as a landmark analysis, excluding patients who died, relapsed, had chronic graft-versus-host disease, or were censored before day +100 following HCT. Of the 89 patients who received TKI maintenance, 77 (87%) received a single TKI and the other 12 (13%) received multiple sequential TKIs. The most common TKIs used for maintenance were dasatinib (n = 50), imatinib (n = 27), and nilotinib (n = 27). As measured from day +100, the adjusted estimates for 5-year relapse (maintenance, 35% versus no maintenance, 26%; P = .11), leukemia-free survival (maintenance, 42% versus no maintenance, 44%; P = .65), or overall survival (maintenance, 61% versus no maintenance, 57%; P = .61) did not differ significantly between patients receiving TKI maintenance or no maintenance. These results remained unchanged in multivariate analysis and were not modified by disease status before transplantation. In conclusion, our data from this day +100 landmark analysis do not demonstrate a significant impact of maintenance TKI therapy on clinical outcomes. The optimal approach to TKI administration in the post-transplantation setting in patients with CML remains undetermined.

High incidence of Pneumocystis jirovecii pneumonia in allogeneic hematopoietic cell transplant recipients in the modern era.

BACKGROUND: International guidelines for Pneumocystis jirovecii pneumonia (PJP) prevention recommend prophylaxis for ≥6 months following allogeneic hematopoietic cell transplantation, and longer in patients with graft-versus-host disease (GVHD) or on immunosuppressive therapy (IST). These recommendations are based on cohorts of patients who did not routinely receive anti-thymocyte globulin (ATG) for GVHD prophylaxis. METHODS: We performed a retrospective chart review of 649 patients, all of whom received ATG as part of GVHD prophylaxis. RESULTS: The cumulative incidence of definite PJP was 3.52% at both 3 and 5 years (median follow up, 1648 days for survivors). PJP occurred in 13 non-GVHD patients between days 207 and 508, due in part to low CD4 T-cell counts (<200 CD4 T cells/µL). PJP occurred in eight GVHD patients between days 389 and 792, due in part to non-adherence to PJP prophylaxis guidelines (discontinuation of PJP prophylaxis at <3 months after discontinuation of IST). Breakthrough PJP infection was not observed in patients receiving prophylaxis with cotrimoxazole, dapsone or atovaquone, whereas three cases were observed with inhaled pentamidine. DISCUSSION: In conclusion, for non-GVHD patients receiving ATG-containing GVHD prophylaxis, 6 months of PJP prophylaxis is inadequate, particularly if the CD4 T-cell count is <200 cells/µL or if there is a high incidence of PJP in the community. For patients with GVHD receiving ATG-containing GVHD prophylaxis, continuing PJP prophylaxis until ≥3 months post-discontinuation of IST is important. Cotrimoxazole, dapsone and atovaquone are preferred over inhaled pentamidine.

Hematopoietic cell transplant outcomes after myeloablative conditioning with fludarabine, busulfan, low-dose total body irradiation, and rabbit antithymocyte globulin.

Optimal conditioning and graft-vs-host disease (GVHD) prophylaxis for hematopoietic cell transplantation (HCT) are unknown. Here, we report on outcomes after low toxicity, myeloablative conditioning consisting of fludarabine, busulfan, and 4 Gy total body irradiation, in combination with thymoglobulin and post-transplant methotrexate and cyclosporine. We retrospectively studied 700 patients with hematologic malignancies who received blood stem cells from 7 to 8/8 HLA-matched unrelated or related donors. Median follow-up of surviving patients was 5 years. At 5 years, overall survival (OS), relapse-free survival (RFS), and chronic GVHD/relapse-free survival (cGRFS) were 58%, 55%, and 40%. Risk factors for poor OS, RFS, and cGRFS were (1). high to very high disease risk index (DRI), (2). high recipient age, and (3). cytomegalovirus (CMV)-seropositive recipient with seronegative donor (D-R+). The latter risk factor applied particularly to patients with lymphoid malignancies. Neither donor other than HLA-matched sibling (7-8/8 unrelated) nor one HLA allele mismatch was risk factors for poor OS, RFS, or cGRFS. In conclusion, the above regimen results in excellent long-term outcomes. The outcomes are negatively impacted by older age, high or very high DRI, and CMV D-R+ serostatus, but not by donor unrelatedness or one HLA allele mismatch.

Rabbit Antithymocyte Globulin Serum Levels: Factors Impacting the Levels and Clinical Outcomes Impacted by the Levels.

Antithymocyte globulin (ATG) levels and clearance vary significantly among patients receiving the same weight-based dose of ATG. To date, ATG area under the curve (AUC), its determinants, and its impact on clinical outcomes have been examined in pediatric hematopoietic cell transplant (HCT) and adult nonmyeloablative HCT. Here we set out to examine ATG AUC in 219 uniformly treated adults undergoing myeloablative allogeneic HCT at our institution. Sera were collected for the determination of pre- or post-HCT ATG AUC. The lowest quintiles of pre- and post-HCT AUC were associated with inferior chronic graft-versus-host disease (GVHD) and relapse-free survival (cGRFS) and a higher risk of acute GVHD, respectively. The highest pre- or post-HCT ATG AUC quintiles were not associated with risk of death, nonrelapse mortality, or relapse. Factors most strongly associated with AUC were day -2 recipient absolute lymphocyte count, body mass index (BMI), and graft lymphocyte content. To achieve ideal pre-HCT AUC (avoiding low AUC to maximize cGRFS) in this HCT setting, ATG dosing will need to take into consideration recipient weight, BMI, and blood and graft lymphocyte counts. Further studies are required to develop a modern ATG dosing schema and to demonstrate that adjusting ATG dose to target a particular AUC is feasible and leads to improved outcomes.

The Concentration of Total Nucleated Cells in Harvested Bone Marrow for Transplantation Has Decreased over Time.

Bone marrow (BM) is an essential source of hematopoietic stem cell grafts for many allogeneic hematopoietic cell transplant (HCT) recipients, including adult patients (for specific diseases and transplantation strategies) and the majority of pediatric recipient. However, since the advent of granulocyte colony-stimulating factor-mobilized peripheral blood stem cell (PBSC) grafts, there has been a significant decrease in the use of BM in HCT, thought to be due mainly to the increased logistical challenges in harvesting BM compared with PBSCs, as well as generally no significant survival advantage of BM over PBSCs. The decreased frequency of collection has the potential to impact the quality of BM harvests. In this study, we examined >15,000 BM donations collected at National Marrow Donor Program centers between 1994 and 2016 and found a significant decline in the quality of BM products, as defined by the concentration of total nucleated cells (TNCs). The mean TNC concentration in BM donations dropped from 21.8 × 106 cells/mL in the earliest era (1994 to 1996) to 18.7 × 106 cells/mL in the most recent era (2012 to 2016) (means ratio, .83; P < .001). This decline in BM quality was seen despite the selection of more donors perceived to be optimal (eg, younger and male). Multivariate regression analysis showed that higher-volume centers (performing >30 collections per era) had better-quality harvests with higher concentrations of TNCs collected. In conclusion, we have identified a significant decrease in the quality of BM collections over time, and lower-volume collection centers had poorer-quality harvests. In this analysis, we could not elucidate the direct cause for this finding, suggesting the need for further studies to investigate the key factors responsible and to explore the impact on transplant recipients.

High incidence of hematologic malignancy relapse after allogeneic transplantation in patients with low Epstein-Barr virus-specific T-cell counts.

BACKGROUND: Association between low counts of herpesvirus-specific T cells and subsequent relapse of hematologic malignancy has been shown in two retrospective studies. METHODS: Here we present results of a prospective validation study. Multiple subsets of Epstein-Barr virus (EBV)-specific T cells were measured in 69 patients on day 56 and 84, using intracellular flow cytometry after incubation of blood mononuclear cells (MNCs) with EBV peptides or lysate. RESULTS: All EBV T-cell subsets measured, both on day 56 and 84, were lower in patients who did versus did not subsequently relapse. This was most significant for day 56 EBV lysate-stimulated CD8 T cells producing interferon-gamma. Patients with day 56 counts of this subset >5/µL had a significantly lower likelihood of relapse compared with those with ≤5/µL (subhazard ratio, 5.7; P = 0.007). Similar significant associations were shown for a total of seven EBV T-cell subsets on day 56 and nine subsets on day 84. However, sensitivity and specificity of relapse prediction using the count of any subset was low (area under the curve of receiver-operator characteristic curve was <0.8). DISCUSSION: In conclusion, the association between EBV T-cell counts and subsequent relapse is valid. However, its clinical utility appears to be limited.

Survival outcomes of allogeneic hematopoietic cell transplants with EBV-positive or EBV-negative post-transplant lymphoproliferative disorder, A CIBMTR study.

BACKGROUND: Post-transplant lymphoproliferative disorders (PTLD) are associated with significant morbidity and mortality following allogeneic hematopoietic cell transplant (alloHCT). Although most PTLD is EBV-positive (EBVpos ), EBV-negative (EBVneg ) PTLD is reported, yet its incidence and clinical impact remain largely undefined. Furthermore, factors at the time of transplant impacting survival following PTLD are not well described. METHODS: Between 2002 and 2014, 432 cases of PTLD following alloHCT were reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). After exclusions, 267 cases (EBVpos  = 222, 83%; EBVneg  = 45, 17%) were analyzed. RESULTS: Two hundred and eight patients (78%) received in vivo T-cell depletion (TCD) with either anti-thymocyte globulin (ATG) or alemtuzumab. Incidence of PTLD was highest using umbilical cord donors (UCB, 1.60%) and lowest using matched related donors (MRD, 0.40%). Clinical features and histology did not significantly differ among EBVpos or EBVneg PTLD cases except that absolute lymphocyte count recovery was slower, and CMV reactivation was later in EBVneg PTLD [EBVpos 32 (5-95) days versus EBVneg 47 (10-70) days, P = .016]. There was no impact on survival by EBV status in multivariable analysis [EBVneg RR 1.42, 95% CI 0.94-2.15, P = .097]. CONCLUSIONS: There is no difference in survival outcomes for patients with EBVpos or EBVneg PTLD occurring following alloHCT and 1-year survival is poor. Features of conditioning and use of serotherapy remain important.

Choosing Wisely BMT: American Society for Blood and Marrow Transplantation and Canadian Blood and Marrow Transplant Group's List of 5 Tests and Treatments to Question in Blood and Marrow Transplantation.

Choosing Wisely encourages dialogue about reducing unnecessary procedures, tests, or treatments in healthcare. The American Society for Blood and Marrow Transplantation (ASBMT) and Canadian Blood and Marrow Transplant Group (CBMTG) established a Choosing Wisely BMT Task Force whose objective was to create a list of top 5 practices in blood and marrow transplantation to be questioned. The Task Force consisted of representatives from ASBMT's Quality Outcomes, Education, and Practice Guidelines committees; ASBMT's Pharmacy Special Interest Group; CBMTG Program Directors; and Center for International Blood and Marrow Transplant Research (CIBMTR). Suggestions for current transplantation practices to question were elicited from the CBMTG Program Directors; members of ASBMT's Quality Outcomes, Practice Guidelines, and Education committees; and chairs of the CIBMTR scientific working committees. We received 119 unique suggestions that were ranked based on their potential impact on harm reduction, cost reduction, necessity of the test or practice, and the strength of available evidence. Through a modified Delphi process, suggestions were narrowed down to 6, which were then subjected to systematic reviews. The final 5 recommendations focus on graft source for patients with aplastic anemia, corticosteroid dose for initial treatment of graft-versus-host-disease, optimal number of umbilical cord blood units for transplantation, graft source in matched unrelated donor transplantation, and use of prophylactic intravenous immunoglobulin in transplant recipients. These Choosing Wisely BMT recommendations are relevant to the current clinical practice of blood and marrow transplantation and focus on tests, treatments, or procedures that may be harmful, wasteful, or for which there is no apparent clinical benefit.

Neurocognitive Dysfunction in Hematopoietic Cell Transplant Recipients: Expert Review from the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and Complications and Quality of Life Working Party of the European Society for Blood and Marrow Transplantation.

Hematopoietic cell transplantation (HCT) is a potentially curative treatment for children and adults with malignant and nonmalignant diseases. Despite increasing survival rates, long-term morbidity after HCT is substantial. Neurocognitive dysfunction is a serious cause of morbidity, yet little is known about neurocognitive dysfunction after HCT. To address this gap, collaborative efforts of the Center for International Blood and Marrow Transplant Research and the European Society for Blood and Marrow Transplantation undertook an expert review of neurocognitive dysfunction after HCT. In this review we define what constitutes neurocognitive dysfunction, characterize its risk factors and sequelae, describe tools and methods to assess neurocognitive function in HCT recipients, and discuss possible interventions for HCT patients with this condition. This review aims to help clinicians understand the scope of this health-related problem, highlight its impact on well-being of survivors, and help determine factors that may improve identification of patients at risk for declines in cognitive functioning after HCT. In particular, we review strategies for preventing and treating neurocognitive dysfunction in HCT patients. Finally, we highlight the need for well-designed studies to develop and test interventions aimed at preventing and improving neurocognitive dysfunction and its sequelae after HCT.

Long-term outcomes among 2-year survivors of autologous hematopoietic cell transplantation for Hodgkin and diffuse large b-cell lymphoma.

BACKGROUND: Autologous hematopoietic cell transplantation (auto-HCT) is a standard therapy for relapsed classic Hodgkin lymphoma (cHL) and diffuse large B-cell lymphoma (DLBCL); however, long-term outcomes are not well described. METHODS: This study analyzed survival, nonrelapse mortality, late effects, and subsequent malignant neoplasms (SMNs) in 1617 patients who survived progression-free for ≥2 years after auto-HCT for cHL or DLBCL between 1990 and 2008. The median age at auto-HCT was 40 years; the median follow-up was 10.6 years. RESULTS: The 5-year overall survival rate was 90% (95% confidence interval [CI], 87%-92%) for patients with cHL and 89% (95% CI, 87%-91%) for patients with DLBCL. The risk of late mortality in comparison with the general population was 9.6-fold higher for patients with cHL (standardized mortality ratio [SMR], 9.6) and 3.4-fold higher for patients with DLBCL (SMR, 3.4). Relapse accounted for 44% of late deaths. At least 1 late effect was reported for 9% of the patients. A total of 105 SMNs were confirmed: 44 in the cHL group and 61 in the DLBCL group. According to a multivariate analysis, older age, male sex, a Karnofsky score < 90, total body irradiation (TBI) exposure, and a higher number of lines of chemotherapy before auto-HCT were risk factors for overall mortality in cHL. Risk factors in DLBCL were older age and TBI exposure. A subanalysis of 798 adolescent and young adult patients mirrored the outcomes of the overall study population. CONCLUSIONS: Despite generally favorable outcomes, 2-year survivors of auto-HCT for cHL or DLBCL have an excess late-mortality risk in comparison with the general population and experience an assortment of late complications. Cancer 2018;124:816-25. © 2017 American Cancer Society.

Epstein-barr virus DNAemia monitoring for the management of post-transplant lymphoproliferative disorder.

BACKGROUND: Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication of allogeneic hematopoietic cell transplantation (HCT). Epstein-Barr virus (EBV) reactivation (detectable DNAemia) predisposes to the development of PTLD. METHODS: We retrospectively studied 306 patients monitored for EBV DNAemia after Thymoglobulin-conditioned HCT to determine the utility of the monitoring in the management of PTLD. DNAemia was monitored weekly for ≥12 weeks post-transplantation. RESULTS: Reactivation was detected in 82% of patients. PTLD occurred in 14% of the total patients (17% of patients with reactivation). PTLD was treated with rituximab only when and if the diagnosis was established. This allowed us to evaluate potential DNAemia thresholds for pre-emptive therapy. We suggest 100,000-500,000 IU per mL whole blood as this would result in unnecessary rituximab administration to only 4-20% of patients and near zero mortality due to PTLD. After starting rituximab (for diagnosed PTLD), sustained regression of PTLD occurred in 25/25 (100%) patients in whom DNAemia became undetectable. PTLD progressed or relapsed in 12/17 (71%) patients in whom DNAemia was persistently detectable. DISCUSSION: In conclusion, for pre-emptive therapy of PTLD, we suggest threshold DNAemia of 100,000-500,000 IU/mL. Persistently detectable DNAemia after PTLD treatment with rituximab appears to have 71% positive predictive value and 100% negative predictive value for PTLD progression/relapse.

Risk factors for post-transplant lymphoproliferative disorder after Thymoglobulin-conditioned hematopoietic cell transplantation.

Epstein-Barr virus (EBV)-induced post-transplant lymphoproliferative disorder (PTLD) occurs frequently when rabbit antithymocyte globulin (ATG) is used in hematopoietic cell transplant (HCT) conditioning. We retrospectively studied 554 patients undergoing ATG-conditioned myeloablative HCT. Strategies used to minimize mortality due to PTLD were either therapy of biopsy-diagnosed PTLD in the absence of EBV DNAemia monitoring (n = 266) or prompt therapy of presumed PTLD (based on clinical/radiologic signs and high EBV DNAemia, in the setting of weekly EBV DNAemia monitoring) (n = 199). Both strategies resulted in similar mortality due to PTLD (0.7% vs 1% at 2 years, P = .43) and similar overall survival (63% vs 67% at 2 years, P = .23) even though there was a trend toward higher PTLD incidence with the prompt therapy. Donor positive with recipient negative EBV (D+R-) serostatus was a risk factor for developing PTLD. Older patient age, HLA-mismatched donor, and graft-versus-host disease were not associated with increased risk of PTLD. In summary, in ATG-conditioned HCT, D+R- serostatus, but not older age, mismatched donor or GVHD is a risk factor for developing PTLD. EBV DNAemia monitoring may be a weak risk factor for developing/diagnosing PTLD; the monitoring coupled with prompt therapy does not improve survival.

Allogeneic Hematopoietic Cell Transplantation for Adult Chronic Myelomonocytic Leukemia.

Allogeneic hematopoietic cell transplantation (HCT) is potentially curative for patients with chronic myelomonocytic leukemia (CMML); however, few data exist regarding prognostic factors and transplantation outcomes. We performed this retrospective study to identify prognostic factors for post-transplantation outcomes. The CMML-specific prognostic scoring system (CPSS) has been validated in subjects receiving nontransplantation therapy and was included in our study. From 2001 to 2012, 209 adult subjects who received HCT for CMML were reported to the Center for International Blood and Marrow Transplant Research. The median age at transplantation was 57 years (range, 23 to 74). Median follow-up was 51 months (range, 3 to 122). On multivariate analyses, CPSS scores, Karnofsky performance status (KPS), and graft source were significant predictors of survival (P = .004, P = .01, P = .01, respectively). Higher CPSS scores were not associated with disease-free survival, relapse, or transplantation-related mortality. In a restricted analysis of subjects with relapse after HCT, those with intermediate-2/high risk had a nearly 2-fold increased risk of death after relapse compared to those with low/intermediate-1 CPSS scores. Respective 1-year, 3-year, and 5-year survival rates for low/intermediate-1 risk subjects were 61% (95% confidence interval [CI], 52% to 72%), 48% (95% CI, 37% to 59%), and 44% (95% CI, 33% to 55%), and for intermediate-2/high risk subjects were 38% (95% CI, 28% to 49%), 32% (95% CI, 21% to 42%), and 19% (95% CI, 8% to 29%). We conclude that higher CPSS score at time of transplantation, lower KPS, and a bone marrow graft are associated with inferior survival after HCT. Further investigation of CMML disease-related biology may provide insights into other risk factors predictive of post-transplantation outcomes.

Outcomes after Umbilical Cord Blood Transplantation for Myelodysplastic Syndromes.

For patients with hematologic malignancies undergoing allogeneic hematopoietic cell transplantation, umbilical cord blood transplantation (UCBT) has become an acceptable alternative donor source in the absence of a matched sibling or unrelated donor. To date, however, there have been few published series dedicated solely to describing the outcomes of adult patients with myelodysplastic syndrome (MDS) who have undergone UCBT. Between 2004 and 2013, 176 adults with MDS underwent UCBT as reported to the Center for International Blood and Marrow Transplant Research. Median age at the time of transplantation was 56 years (range, 18-73 years). The study group included 10% with very low, 23% with low, 19% with intermediate, 19% with high, and 13% with very high-risk Revised International Prognostic Scoring System (IPSS-R) scores. The 100-day probability of grade II-IV acute graft-versus-host disease (GVHD) was 38%, and the 3-year probability of chronic GVHD was 28%. The probabilities of relapse and transplantation-related mortality (TRM) at 3 years were 32% and 40%, respectively, leading to a 3-year disease-free survival (DFS) of 28% and an overall survival (OS) of 31%. In multivariate analysis, increasing IPSS-R score at the time of HCT was associated with inferior TRM (P = .0056), DFS (P = .018), and OS (P = .0082), but not with GVHD or relapse. The presence of pretransplantation comorbidities was associated with TRM (P = .001), DFS (P = .02), and OS (P = .001). Reduced-intensity conditioning was associated with increased risk of relapse (relative risk, 3.95; 95% confidence interval, 1.78-8.75; P < .001), and although a higher proportion of myeloablative UCBTs were performed in patients with high-risk disease, the effect of conditioning regimen intensity was the same regardless of IPSS-R score. For some individuals who lack a matched sibling or unrelated donor, UCBT can result in long-term DFS; however, the success of UCBT in this population is hampered by a high rate of TRM.