Incidence,Risk Factors,and Long-Term Outcomes of Sclerotic Graft-versus-Host Disease after Allogeneic Hematopoietic Cell Transplantation

Sclerotic chronic graft-versus-host disease (sclGVHD) is associated with significant morbidity and a poor quality of life. We reviewed 502 patients diagnosed with chronic GVHD and analyzed the incidence and risk factors of sclGVHD and long-term outcomes and immunosuppressive therapy (IST) cessation in patients with sclGVHD. With a median onset at 18 months the cumulative incidence of sclGVHD was estimated at 22.6% at 5 years (95% confidence interval, 18.6% to 26.8%). Univariate and multivariate analysis identified 2 risk factors for sclGVHD: non-T cell depletion (hazard ratio [HR] 9.09, P < .001) and peripheral blood stem cell (HR 3.87, P < .001). Overall survival (OS) at 5 years was significantly better in the sclGVHD group (88.1%) compared with the non-sclGVHD group (62.7%; P < .001), as were nonrelapse mortality (7.3% versus 21.5% at 5 years) and relapse rates (9.1% versus 19.3% at 5 years). There was no difference in the rate of IST cessation at 5 years (44.8% versus 49.9%, P = .312), but there was a trend of longer IST duration in the sclGVHD group compared with the non-sclGVHD group (median 71.6 months versus 62.9 months). In conclusion, T cell depletion and graft source affect the risk of sclGVHD. SclGVHD did not adversely affect long-term outcomes or IST duration.     

Risk Factors for Invasive Fungal Disease after Allogeneic Hematopoietic Stem Cell Transplantation: A Single Center Experience

Invasive fungal disease (IFD) is a major cause of morbidity and mortality after hematopoietic stem cell transplantation (HCT). We performed a retrospective review of 271 adults with a hematologic malignancy undergoing allogeneic HCT to determine the incidence of and risk factors for IFD and to examine the impact of IFD on nonrelapse mortality and overall survival. We defined IFD using standard criteria and selected proven and probable cases for analysis. Diagnoses in the study group included acute leukemia (42%), non-Hodgkin lymphoma (24%), myelodysplastic syndrome (15%), chronic lymphocytic leukemia (5%), and other hematologic disorders (14%). Conditioning included reduced-intensity (64%) and myeloablative (36%) regimens. Donor sources were HLA-matched sibling (60%), matched unrelated (20%), haploidentical (12%), and cord blood (8%). A total of 51 episodes of IFD were observed in 42 subjects (15%). Aspergillus spp (47%) was the most frequent causative organism, followed by Candida spp (43%). The majority of IFD cases (67%) were reported after day +100 post-HCT. In multivariate analysis, haploidentical donor transplantation (hazard ratio [HR], 3.82; 95% confidence interval [CI], 1.49-9.77; P = .005) and grade II-IV acute graft-versus-host disease (HR, 2.55; 95% CI, 1.07-6.10; P = .03) were risk factors for the development of IFD. Conversely, higher infused CD34⁺ cell dose was associated with a lower risk of IFD (HR, 0.80; 95% CI, 0.68-0.94; P = .006, per 1 × 10⁶ cells/kg increase in CD34⁺ cell infusion). IFD-related mortality was 33.3%. Nonrelapse mortality was significantly higher in patients who developed IFD compared with those without IFD (P < .001, log-rank test). Patients with IFD had lower overall survival (5.8 months versus 76.1 months; P < .001, log-rank test). Further studies exploring strategies to increase the infused cell dose and determine adequate prophylaxis, especially against aspergillus, beyond day +100 are needed.     

C-Reactive Protein Levels at Diagnosis of Acute Graft-versus-Host Disease Predict Steroid-Refractory Disease,Treatment-Related Mortality,and Overall Survival after Allogeneic Hematopoietic Stem Cell Transplantation

Acute graft-versus-host disease (aGVHD) remains a cause of excessive morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Primary treatment consists of high-dose corticosteroids, but a small group of patients develop steroid-refractory disease, and their prognosis is especially poor. There is experimental evidence that coexisting inflammation aggravates aGVHD. Because C-reactive protein (CRP) is a systemic inflammatory marker, we aimed to investigate whether plasma CRP concentrations at the diagnosis of aGVHD can predict the risk of failing first-line therapy and developing steroid-refractory disease. We retrospectively studied 461 patients who underwent HSCT between 2010 and 2015. aGVHD grade II-IV was diagnosed in 148 patients (32%). CRP level and total white blood cell, lymphocyte, and neutrophil counts were available for all patients at the time of aGVHD diagnosis. According to local protocol, patients with failed response to high-dose steroid therapy (2?mg/kg) were treated with the TNF-α inhibitor infliximab and categorized as having steroid-refractory disease. Of 148 patients with grade II-IV aGVHD, 28 (19%) developed steroid-refractory disease. In these patients, plasma CRP concentration at diagnosis ranged between <1 and 253?mg/L. CRP levels were significantly higher in patients who developed steroid-refractory disease compared with those who responded to high-dose corticosteroid therapy (odds ratio, 1.50; 95% confidence interval, 1.18-1.93; P?=?.001). This translated into significantly increased transplantation-related mortality and decreased overall survival in the patients with high CRP levels. Total white blood cell, lymphocyte, and neutrophil counts were not associated with steroid resistance in the patients with aGVHD. These results suggest that CRP level at diagnosis is a valid predictor of the development of steroid-refractory disease in patients who develop grade II-IV aGVHD after HSCT.     

Impact of Cytomegalovirus Replication and Cytomegalovirus Serostatus on the Outcome of Patients with B Cell Lymphoma after Allogeneic Stem Cell Transplantation

Cytomegalovirus (CMV) replication after allogeneic hematopoietic stem cell transplantation (HSCT) was historically associated with increased nonrelapse mortality (NRM). More recently, different groups have reported an association between CMV replication and reduced risk of acute myeloid leukemia (AML) relapse. Given the conflicting results, we evaluated the impact of CMV replication and other covariates on the outcome of a retrospective cohort of 265 adults with B cell lymphoma receiving allogeneic HSCT from HLA-identical siblings or alternative donors. In time-dependent multivariate analysis, CMV replication, evaluated by pp65 antigenemia, had no independent effect on the risk of relapse (hazard ratio [HR], 1.0; 95% confidence interval [CI], .6 to 1.6; P = .9), although it was associated with a reduced overall survival (HR, 2.0; 95% CI, 1.3 to 3.2; P = .001) and an increased NRM (HR, 2.5; 95% CI, 1.1 to 5.3; P = .01). Consistently, donor and/or recipient CMV seropositivity were not associated with a different outcome relative to CMV double-negative serostatus. In multivariate models, a diagnosis of follicular lymphoma (P < .0001) and pretransplantation complete remission status (P < .0001) were the main independent predictors for improved relapse-free survival. In summary, contrary to what is observed in patients with AML, this report identifies no independent role for CMV replication or serostatus on the relapse of patients with B cell lymphomas undergoing allogeneic HSCT.     

Phase I Trial of Brentuximab Vedotin for Steroid-Refractory Chronic Graft-versus-Host Disease after Allogeneic Hematopoietic Cell Transplantation

We conducted a phase I study of brentuximab vedotin (BV), an antibody–drug conjugate targeting CD30, for the treatment of steroid-refractory chronic graft-versus-host disease (cGVHD). A modified 3?+?3 study design was used with the primary endpoint to determine the maximum tolerated dose of BV in this population. Escalating doses of BV were planned, starting with .6?mg/kg every 3 weeks (dose level 0) and increasing by .3?mg/kg per dose level. BV was administered in 21-day cycles for up to 16 cycles of therapy. Nineteen patients were enrolled on the study, with 2 withdrawing consent before dosing. The median number of cycles of therapy was 4 (range, 1 to 16). Reasons for stopping therapy prematurely included toxicities (n?=?9), patient decision (n?=?3), lack of response (n?=?2), and death (n?=?1). There were 2 dose-limiting toxicities observed: posterior reversible encephalopathy syndrome (cohort 4, grade 3) and sepsis (cohort 4, grade 4). The maximum tolerated dose was not reached because the trial was prematurely closed due to toxicity. Seven patients (41%) developed grade 3 or 4 adverse events that were attributed to therapy, including 4 patients who developed moderate or severe peripheral neuropathy that led to cessation of treatment in each case. According to National Institutes of Health cGVHD response criteria, 8 patients (47%) experienced a partial response, whereas 9 patients (53%) had a lack of response. There were no complete responses observed. Eleven patients (65%) were able to decrease their systemic corticosteroid dose by ≥50% by 6 months after initiation of BV, including 3 patients who were able to stop corticosteroids completely. The median soluble CD30 level before therapy was 61.5?ng/mL (range, 7.8 to 474.9); however, we did not observe any association between soluble CD30 level and cGVHD severity at enrollment or clinical responses to BV. In conclusion, BV may have activity in treatment of steroid-refractory cGVHD, yet its use is limited by treatment-emergent toxicities, including peripheral neuropathy. Continued efforts to investigate targeted approaches to cGVHD that do not cause broad immunosuppression are needed.     

Control of Cytomegalovirus Viremia after Allogeneic Stem Cell Transplantation: A Review on CMV-Specific T Cell Reconstitution

Recipients of allogeneic stem cell transplantation (alloSCT) are at risk for reactivation of endogenous herpesviruses due to profound and prolonged T cell deficiency following conditions such as graft-versus-host disease, immunosuppression, and/or T cell depletion. Reactivation of endogenous cytomegalovirus (CMV) is the most frequently occurring herpesvirus reactivation following alloSCT. Antiviral medication is often used in pre-emptive treatment strategies initiated when increases in CMV viral loads are detected as a result of active reactivation of the virus. Despite pre-emptive antiviral treatment, the incidence of CMV disease in CMV-seropositive alloSCT patients is still 10% at 1 year following alloSCT. This illustrates the necessity for adequate CMV-specific T cell immunity for long-term control of CMV and prevention of CMV disease. In this review, we analyzed the available studies on the influence of donor CMV status on CMV-specific T cell reconstitution and CMV disease. Furthermore, we reviewed the available studies on the safety and efficacy of adoptive transfer of donor CMV-specific T cells for the prevention and treatment of CMV disease following alloSCT, including studies on adoptive transfer of third-party CMV-specific T cells as a possible alternative when donor T cells are not available.     

CD34+-Selected Stem Cell Boost without Further Conditioning for Poor Graft Function after Allogeneic Stem Cell Transplantation in Patients with Hematological Malignancies

We retrospectively analyzed outcomes of a CD34⁺-selected stem cell boost (SCB) without prior conditioning in 32 patients (male/22; median age of 54 years; range, 20 to 69) with poor graft function, defined as neutrophils ≤1.5 x 10⁹/L, and/or platelets ≤30 x 10⁹/L, and/or hemoglobin ≤8.5 g/dL). The median interval between stem cell transplantation and SCB was 5 months (range, 2 to 228). The median number of CD34⁺ and CD3⁺ cells were 3.4 x 10⁶/kg (.96 to 8.30) and 9 x 10³/kg body weight (range, 2 to 70), respectively. Hematological improvement was observed in 81% of patients and noted after a median of 30 days (range, 14 to 120) after SCB. The recipients of related grafts responded faster than recipients of unrelated grafts (20 versus 30 days, P = .04). The cumulative incidence of acute (grade II to IV) and chronic graft-versus-host disease (GVHD) after SCB was 17% and 26%, respectively. Patients with acute GVHD received a higher median CD3⁺ cell dose. The 2-year probability of overall survival was 45%. We suggest that SCB represents an effective approach to improve poor graft function post transplantation, but optimal timing of SCB administration, anti-infective, and GVHD prophylaxis needs further evaluation.     

Clostridium Difficile Infection after Allogeneic Hematopoietic Stem Cell Transplant: Strain Diversity and Outcomes Associated with NAP1/027

Allogeneic hematopoietic stem cell transplantation (HSCT) recipients are at high risk for developing Clostridium difficile infection (CDI). We studied the incidence, risk factors, NAP1/027 prevalence, and clinical outcomes, including acute lower gastrointestinal graft-versus-host disease (GI GVHD), associated with early CDI in this population. A retrospective review was conducted of patients who underwent allogeneic HSCT at Memorial Sloan Kettering Cancer Center from January 1, 2005 to September 30, 2010. Early CDI was defined as infection occurring from day −10 to day +40 from stem cell infusion. Among 793 patients who received allogeneic HSCTs, early CDI occurred in 11.9%; 56% cases were between day −5 and day +5. Overall incidence was 25.2 cases/10,000 at-risk days. There was a high prevalence of NAP1/027 strains during peak incidence (61% in 2008). NAP1/027 was the most common strain in both adult and pediatric cases (24% and 23%, respectively). CDI was clinically mild, including those due to NAP1/027. Metronidazole was the primary treatment for 91 of 94 patients, 7 of 8 cases refractory to metronidazole had no response to vancomycin, and none was due to NAP1/027. Relapse of CDI was common (31%). The cumulative incidence of GI GVHD in patients with and without early CDI was 6.8% and 8%, respectively (P = .5). Most cases of CDI occurred during conditioning or immediately after transplant. Despite high prevalence of NAP1/027, we found only mild disease. Most patients were treated successfully with metronidazole, irrespective of NAP1/027 status. There was no significant association between early CDI and subsequent development of GI GVHD. This study demonstrates the high incidence of CDI early after allogeneic HSCT with wide diversity among infecting strains. Despite the high prevalence of NAP1/027, the disease is mild but relapses are common. No association was found between CDI and subsequent development of GI GVHD.     

Higher Peak Tacrolimus Concentrations after Allogeneic Hematopoietic Stem Cell Transplantation Increase the Risk of Endothelial Cell Damage Complications

Noninfectious transplantation-related complications (TRCs) such as graft-versus-host disease (GVHD) and endothelial cell damage (TRC-EC) are critical after allogeneic hematopoietic stem cell transplantation. Tacrolimus (TAC) is used to control GVHD. Hypertension and renal failure are common adverse events after TAC treatment. Higher blood concentrations of TAC would be expected to reduce the risk of GVHD but may increase TRC-EC. TRC-EC often develops in patients with GVHD; thus, it is difficult to clinically determine the proper intensity of immunosuppression. We therefore evaluated the impact of weekly mean/peak TAC blood concentrations (PTCs) on TRC-EC occurrence and prognosis. Patients (N = 295) who received TAC as a GVHD prophylaxis at our institute from 2009 to 2016 were eligible for this retrospective study. Forty-three patients were diagnosed with TRC-EC: 8 with sinusoidal obstructive syndrome, 28 with transplant-associated microangiopathy, and 7 with idiopathic pneumonia syndrome. The cumulative incidence of TRC-EC at 12 months was 13.8% (95% confidence interval [CI] 10.1% to 18.1%). After multivariate analysis high PTCs during days 22 to 28 (hazard ratio [HR] 2.47; 95% CI, 1.37 to 4.45; P < .01) and grades II to IV acute GVHD (HR, 5.61; 95% CI, 2.99 to 10.53; P < .01) were associated with TRC-EC occurrence. The probability of overall survival (OS) at 12 months was 67.7% (95% CI, 61.7% to 73.0%). After multivariate analysis TRC-EC diagnosis (HR, 2.47, 95% CI, 1.59 to 3.83; P < .01) and high-risk disease (HR, 1.75; 95% CI, 1.17 to 2.61; P < .01) were significantly associated with poor OS. In conclusion, higher PTC during days 22 to 28 increased the risk of TRC-EC. TRC-EC development was associated with poor OS.     

Risk-Factor Analysis of Poor Graft Function after Allogeneic Hematopoietic Stem Cell Transplantation

The objective of this study was to investigate the main risk factors for poor graft function (PGF) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), to allow the improvement of transplantation outcomes through preventive measures. Clinical data for 124 patients who received allo-HSCT were analyzed retrospectively. There were 83 males (66.9%) and 41 females (33.1%) with a median age of 28 years (4-60 years). The median follow-up time was 7 months (1-116 months). Factors analyzed included age, gender, disease diagnosis, source of hematopoietic stem cells, donor type, human leukocyte antigen (HLA) matching, conditioning regimen, numbers of infused mononuclear cells and CD34⁺ cells, donor-recipient sex and blood-type matching, prophylactic treatment of graft-versus-host disease (GVHD), grades of GVHD, Epstein-Barr virus or cytomegalovirus (CMV) infection, post-transplantation lymphoproliferative disorders and hepatic veno-occlusive disease. Data were analyzed by univariate and multivariate conditional logistic regression analyses. Among the 124 patients who underwent allo-HSCT, 15 developed PGF (12.1%). Univariate logistic regression analysis identified age, donor-recipient blood type and CMV infection (in 30 days) as potential risk factors for PGF. Multivariate analysis of factors with P<0.1 in univariate analysis showed that age, donor-recipient blood type and CMV infection (in 30 days) were significant risk factors for PGF. Patients were divided into subgroups based on age <20, 20-30, 30-40, and >40 years. The risk of PGF increased 2.747-fold (odds ratio (OR)=2.625, 95% confidence interval: 1.411-5.347) for each increment in age level. Patients with mismatched blood type (OR=4.051) or CMV infection (OR=9.146) had an increased risk of PGF. We conclude that age, donor-recipient blood-type matching and CMV infection are major risk factors for PGF after allo-HSCT.     

Level of Vascular Endothelial Growth Factor Predicts Both Relapse and Nonrelapse Mortality after Allogeneic Hematopoietic Stem Cell Transplantation

Although the prognostic significance of vascular endothelial growth factor (VEGF) has been researched extensively in patients with hematologic malignancies undergoing chemotherapy, its role in allogeneic hematopoietic stem cell transplantation (HSCT) requires further investigation. The present study evaluated the associations between VEGF level and relapse rate and early complications after HSCT. VEGF levels were analyzed in 91 consecutive patients before the start of conditioning, on day 0, on the day of engraftment, and on the day of diagnosis of veno-occlusive disease (VOD). Compared with a normal level, an elevated high VEGF-A level before conditioning was associated with an increased 2-year relapse rate (55% versus 24%, P = .003; hazard ratio [HR], 3.25; 95% confidence interval [CI], 1.49 to 7.08) and decreased event-free survival (20% versus 44%; P = .022; HR, 2.03; 95% CI, 1.11 to 3.72). No association was found between VEGF level and the incidence of acute GVHD (P > .05). In patients with VOD, VEGF-A level was elevated on day 0 and on the day of VOD diagnosis (P < .05). A low VEGF-A level on day 0 was associated with reduced nonrelapse mortality (14% versus 35%; P = .048; HR, 0.32; 95% CI, 0.10 to 0.99). Our results indicate that a high VEGF-A level before HSCT increases the risk of relapse, and a high level after conditioning is associated with increased risks of early complications and nonrelapse mortality.     

Biology-Driven Approaches to Prevent and Treat Relapse of Myeloid Neoplasia after Allogeneic Hematopoietic Stem Cell Transplantation

The curative potential of allogeneic hematopoietic cell transplantation (allo-HCT) in the treatment of acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) relies mainly on the graft-versus-leukemia effect. Relapse after allo-HCT occurs in a considerable proportion of patients and has a dismal prognosis, with still very limited curative potential. This review provides an overview of the established and evolving approaches to preventing or treating relapse of AML and MDS after allo-HCT, in the context of novel insight into the biology of relapse. Established prophylactic measures to prevent relapse include optimized conditioning and graft-versus-host disease (GVHD) prophylaxis, as well as donor lymphocyte infusion (DLI) for high-risk patients; novel immunomodulatory interventions and maintenance approaches are still experimental. Improved diagnostics can detect persistent or recurring disease at a molecular level, enabling early preemptive interventions. Established options include hypomethylating agents and DLI. Standard treatments for hematologic relapse include chemotherapy, cessation of immunosuppressive treatment, and DLI. Experimental approaches include molecular targeted therapies, novel immunomodulatory treatments, and second allo-HCT. For all interventions, the potential risks, including occurrence of GVHD, must be weighed against the benefits individually in each patient. Concurrently, prevention and treatment of relapse after allo-HCT remain challenging and unmet medical needs.     

Late Gastrointestinal Complications of Allogeneic Hematopoietic Stem Cell Transplantation in Adults

Gastrointestinal (GI) complications including graft-versus-host disease (GVHD) are a major cause of morbidity and mortality in allogenic stem transplant recipients. Although several studies have previously looked into the acute GI complications, fewer smaller studies have reported late complications. In this large study we focus on the late (100 days post-transplant) GI complications in allogenic stem transplant recipients. In this single-center, retrospective study of all adult allogenic stem cell transplant recipients who had their transplant at Duke University over a 6-year period, 479 patients underwent allogenic stem cell transplant, of whom 392 recipients survived for at least 100 days post-transplant. Late GI symptoms were noted in 71 patients, prompting endoscopic evaluation. The primary endpoint of our study was the diagnosis of GI-GVHD based on endoscopic findings, whereas overall survival and nonrelapse mortality were the secondary endpoints. Of the 71 patients who underwent endoscopy, 45 (63%) had GI-GVHD. Of these 45 patients, 39 (87%) had late acute GVHD, 1 (2%) had chronic GVHD, and 5 patients (11%) had overlap disease. Of the patients who did not have GVHD, the symptoms were mostly related to infectious and inflammatory causes. Less common causes included drug toxicity, food intolerance, disease relapse, and motility issues. In a multivariate analysis the factors most indicative of GI-GVHD were histologic findings of apoptosis on the tissue specimen (odds ratio, 2.35; 95% confidence interval, 1.18 to 4.70; P?=?.015) and clinical findings of diarrhea (odds ratio, 5.43; 95% confidence interval, 1.25 to 23.54; P?=?.024). The median survival time from the first endoscopy was 8.5 months. The incidence of nonrelapse mortality at 6 months was 31% in patients with GI-GVHD and 19% in patients without GI-GVHD (P?=?.42). All patients with GI-GVHD were on steroid therapy, and 31% of them received total parenteral nutrition. In our population close to one-fifth of allogenic transplant recipients experienced late GI complications, warranting endoscopic evaluation. Most of these patients were found to have GI-GVHD that had a high incidence of nonrelapse mortality at 6 months and close to one-third of these patients needed total parenteral nutrition.     

Kinetics and Risk Factors of Relapse after Allogeneic Stem Cell Transplantation in Children with Leukemia: A Long-Term Follow-Up Single-Center Study

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an established treatment for high-risk hematological malignancies in the pediatric population, but relapse remains the leading cause of death. We analyzed risk factors associated with relapse.Data from 353 allo-HSCTs from 1989 to 2015 in our center were studied retrospectively. We performed a multivariate analysis of pre- and postransplantation variables and developed a predictive risk score for relapse using the significant factors in this training cohort. The results were confirmed in a validation cohort of 90 allo-HSCTs done in our institution from 2016 to the present.A total of 104 patients relapsed after allo-HSCT, with a relapse cumulative incidence of 31 ± 2%. In multivariate analysis, only 2 variables influenced relapse: disease phase (advanced versus early, HR, 2.84; 95% CI, 1.76 to 4.57; P?=?.001) and presence of chronic graft-versus-host disease (GVHD) (acute GVHD versus chronic GVHD [HR, 4.27; 95% CI, 1.99 to 9.15; P?=?.0001] and no GVHD versus chronic GVHD [HR, 6.86; 95% CI, 3.63 to 12.97] P?=?.0001]. Applying the personalized risk score (0 to 3), the relapse cumulative incidence was 70 ± 5% in patients with a score of 3 (without GVHD and in the advanced phase) compared with 6 ± 4% in patients with a score of 0 (with chronic GVHD and in an early phase). This score has been verified in the validation set. With a median follow-up of 54 months, the disease-free survival (DFS) and overall survival rate were 37 ± 3% and 45 ± 4%, respectively.The association of GVHD with the graft-versus-leukemia effect is clearly established in our study, and the form of GVHD associated with less relapse and the best DFS is the classical form of chronic GVHD according to the National Institutes of Health classification. The proposed relapse risk score was validated in an independent cohort and allows personalization of the prognosis.     

Risk Factor and Clinical Outcome of Bronchiolitis Obliterans Syndrome after Allogeneic Hematopoietic Stem Cell Transplantation

PurposeThe development of bronchiolitis obliterans syndrome (BOS) after allogeneic hematopoietic stem cell transplantation (HSCT) deteriorates patients'' quality of life. This study aimed to analyze the prevalence, clinical features, risk factors and prognostic factors of BOS.ResultsOf 860 patients who survived for ≥100 days, 36 (4.2%) met the diagnostic criteria. The duration of BOS development after transplantation was 466.00 (284.00–642.75) [median (interquartile range)] days. The risk factor for the development of BOS was peripheral blood as the stem cell source with a hazard ratio (HR) of 2.550 [95% confidence interval (CI): 1.274–5.104, p=0.008]. In multivariate analysis, pretransplant FEV₁/FVC (HR: 0.956, 95% CI: 0.921–0.993, p=0.020) and time from HSCT to diagnosis of BOS (HR: 0.997, 95% CI: 0.994–0.999, p=0.009) were independent prognostic factors associated with mortality.ConclusionPeripheral blood as a stem cell source is a risk factor for the development of BOS. A decreased pretransplant FEV₁/FVC and shorter duration of time from transplantation to diagnosis of BOS are poor prognostic factors for BOS.     

Role of Acute Graft-Versus-Host Disease in the Risk of Bacteremia and Invasive Fungal Disease after Allogeneic Hemopoietic Stem Cell Transplantation in Children. Results from a Single-Center Observational Study

Data on epidemiology of severe infectious complications, ie, bacteremia or invasive fungal disease (IFD), in children with acute graft-versus-host disease (aGVHD) after allogeneic hemopoietic stem cell transplantation (HSCT) are scarce. In a retrospective, single-center study, we analyzed the risk (hazard ratio [HR]) and the rate (episodes/1000 patients days at risk) of bacteremias and IFD in children receiving allogeneic HSCT, according to the type of donor (matched related [MRD] or alternative [AD]) and presence and grade of aGVHD. From 2000 to 2009, 198 children receiving 217 allogeneic HSCT developed 134 severe infectious episodes (103 bacteremias and 31 IFD). The type of donor (AD versus MRD) was the most important risk factor for the severe infections (P = .0052). In separate multivariable analysis for bacteremia and IFD, children receiving an AD HSCT had increased HR and rate of bacteremia compared with those receiving a MRD transplantation (P = .0171 and P = .0001, respectively), whereas the HR and the rate of IFD were significantly influenced by the grade of aGVHD (P = .0002 and P < .0001, respectively). Finally, infectious episodes occurred late after HSCT, especially in presence of severe aGVHD, and bacteremias were 3 to 6 times more frequent than IFD. These data may be important to design management strategies of infections in pediatric allogeneic HSCT.     

Innate Immune Recovery Predicts CD4+ T Cell Reconstitution after Hematopoietic Cell Transplantation

Innate immune cells are the first to recover after allogeneic hematopoietic cell transplantation (HCT). Nevertheless, reports of innate immune cell recovery and their relation to adaptive recovery after HCT are largely lacking. Especially predicting CD4⁺ T cell reconstitution is of clinical interest, because this parameter directly associates with survival chances after HCT. We evaluated whether innate recovery relates to CD4⁺ T cell reconstitution probability and investigated differences between innate recovery after cord blood transplantation (CBT) and bone marrow transplantation (BMT). We developed a multivariate, combined nonlinear mixed-effects model for monocytes, neutrophils, and natural killer (NK) cell recovery after transplantation. A total of 205 patients undergoing a first HCT (76 BMT, 129 CBT) between 2007 and 2016 were included. The median age was 7.3years (range, .16 to 23). Innate recovery was highly associated with CD4⁺ T cell reconstitution probability (P < .001) in multivariate analysis correcting for covariates. Monocyte (P < .001), neutrophil (P < .001), and NK cell (P < .001) recovery reached higher levels during the first 200days after CBT compared with BMT. The higher innate recovery after CBT may be explained by increased proliferation capacity (measured by Ki-67 expression) of innate cells in CB grafts compared with BM grafts (P?=?.041) and of innate cells in vivo after CBT compared with BMT (P?=?.048). At an individual level, patients with increased innate recovery after either CBT or BMT had received grafts with higher proliferating innate cells (CB; P?=?.004, BM; P?=?.01, respectively). Our findings implicate the use of early innate immune monitoring to predict the chance of CD4⁺ T cell reconstitution after HCT, with respect to higher innate recovery after CBT compared with BMT.     

Multicenter Analyses Demonstrate Significant Clinical Effects of Minor Histocompatibility Antigens on GvHD and GvL after HLA-Matched Related and Unrelated Hematopoietic Stem Cell Transplantation

The effect of minor H antigen mismatching on the occurrence of graft-versus-host disease (GvHD) and graft-versus-leukemia (GvL) after HLA-matched hematopoietic stem cell transplantation (HSCT) has mainly been demonstrated in single-center studies. Yet, the International Histocompatibility and Immunogenetics Workshops (IHIW) provide a collaborative platform to execute crucial large studies. In collaboration with 20 laboratories of the IHIW, the roles of 10 autosomal and 10 Y chromosome–encoded minor H antigens were investigated on GvHD and relapse incidence in 639 HLA-identical related donor (IRD) and 210 HLA-matched unrelated donor (MUD) HSCT recipients. Donor and recipient DNA samples were genotyped for the minor H antigens HA-1, HA-2, HA-3, HA-8, HB-1, ACC-1, ACC-2, SP110, PANE1, UGT2B17, and HY. The correlations with the primary outcomes GvHD (acute or chronic GvHD), survival, and relapse were statistically analyzed. The results of these multicenter analyses show that none of the HLA class I–restricted HY antigens were found to be associated with any of the primary outcomes. Interestingly, of the HLA class II–restricted HY antigens analyzed, HLA-DQ5 positive recipients showed a significantly increased GvHD-free survival in female-to-male HSCT compared with male-to-female HSCT (P = .013). Yet, analysis of the overall gender effect, thus independent of the known HY antigens, between the gender groups demonstrated an increased GvHD incidence in the female-to-male transplantations (P < .005) and a decreased GvHD-free survival in the female-to-male transplantations (P < .001). Of all autosomally encoded minor H antigens, only mismatching for the broadly expressed minor H antigen HA-8 increased the GvHD incidence in IRD HSCT (Hazard ratio [HR] = 5.28, P < .005), but not in MUD HSCT. Most striking was the influence of hematopoietic restricted minor H antigens on GvL as mismatching for hematopoietic minor H antigens correlated with lower relapse rates (P = .078), higher relapse-free survival (P = .029), and higher overall survival (P = .032) in recipients with GvHD, but not in those without GvHD. In conclusion, the significant GvHD effect of the broadly expressed minor H antigen HA-8 favors matching for HA-8 in IRD, but not in MUD, patient/donor pairs. The GvHD-GvL association demonstrating a significant lower relapse in hematopoietic minor H antigen mismatched patient/donor pairs underlines their clinical applicability for adoptive immunotherapy, enhancing the GvL effect in a GvHD controllable manner.     

Validation of the Disease Risk Index for Outcome of Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplantation after T Cell Depletion

Identification of pretransplantation risk factors is important in evaluating patient outcomes after hematopoietic stem cell transplantation. Current scoring schemes, such as the European Group for Blood and Marrow Transplantation risk score or the Hematopoietic Cell Transplantation-Specific Comorbidity Index, may under-rate disease and disease status at the time of transplantation. The recently published Disease Risk Index (DRI) specifically investigates these aspects by defining 4 risk groups (low, intermediate, high, very high) with significant differences in overall survival (OS). We retrospectively investigated whether the DRI could be applied at the transplantation center of Geneva's University Hospitals (Geneva, Switzerland), where 64% of patients are underwent transplantation with T cell–depleted grafts (TDEP). We analyzed 409 patients with various hematological malignancies who underwent transplantation between January 1998 and October 2012. Using the DRI, the 4-year OS for the low, intermediate, high, and very high groups was 82%, 53%, 27%, and 31%, respectively (P < .0001). For TDEP patients, the 4-year OS for low, intermediate, and high overall risk groups was 86%, 53%, and 33%, respectively (P < .0001). As patients in the very high overall risk group are usually not eligible for TDEP, our group comprised too few patients (n = 3) for meaningful analysis. For non-TDEP patients, the 4-year OS for low, intermediate, high, and very high overall risk groups was 63%, 54%, 22%, and 18%, respectively (P < .0001). Our results confirm the prognostic value of the DRI in a cohort with a majority of TDEP patients.