Status of Natural Killer Cell Recovery in Day 21 Bone Marrow after Allogeneic Hematopoietic Stem Cell Transplantation Predicts Clinical Outcome

Rapid immune recovery following allogeneic hematopoietic stem cell transplantation (allo-HSCT) is important for clinical outcome prediction. In most studies, immune recovery after allo-HSCT is monitored via peripheral blood. However, few reports regarding the status of absolute lymphocyte subsets in the bone marrow (BM) microenvironment have been undertaken. Therefore, we evaluated the clinical impact of immune recovery in the early period following allo-HSCT using BM samples. We showed that delayed natural killer cell recovery was independently associated with a poor prognosis for overall survival (hazard ratio [HR], 3.07; 95% confidence interval [CI], 1.37- 6.89; P?=?.007), progression-free survival (HR, 3.42; 95% CI, 1.47-7.94; P?=?.004), and nonrelapse mortality (HR, 6.68; 95% CI, 1.82-25.0; P?=?.004) by multivariate analysis. In addition, low NK cell counts were associated with the presence of 1 or more bacterial, viral, or fungal infections. Our results indicate that investigating absolute lymphocyte subsets in BM in the early phase following allo-HSCT can be useful for predicting and improving survival outcomes.     

Donor Chimerism Early after Reduced-Intensity Conditioning Hematopoietic Stem Cell Transplantation Predicts Relapse and Survival

The impact of early donor cell chimerism on outcomes of T cell–replete reduced-intensity conditioning (RIC) hematopoietic stem cell transplantation (HSCT) is ill defined. We evaluated day 30 (D30) and 100 (D100) total donor cell chimerism after RIC HSCT undertaken between 2002 and 2010 at our institution, excluding patients who died or relapsed before D30. When available, donor T cell chimerism was also assessed. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), relapse, and nonrelapse mortality (NRM). We evaluated 688 patients with hematologic malignancies (48% myeloid and 52% lymphoid) and a median age of 57 years (range, 18 to 74) undergoing RIC HSCT with T cell–replete donor grafts (97% peripheral blood; 92% HLA-matched), with a median follow-up of 58.2 months (range, 12.6 to 120.7). In multivariable analysis, total donor cell and T cell chimerism at D30 and D100 each predicted RIC HSCT outcomes, with D100 total donor cell chimerism most predictive. D100 total donor cell chimerism <90% was associated with increased relapse (hazard ratio [HR], 2.54; 95% confidence interval [CI], 1.83 to 3.51; P < .0001), impaired PFS (HR, 2.01; 95% CI, 1.53 to 2.65; P < .0001), and worse OS (HR, 1.50; 95% CI, 1.11 to 2.04, P = .009), but not with NRM (HR, .76; 95% CI, .44 to 2.27; P = .33). There was no additional utility of incorporating sustained D30 to D100 total donor cell chimerism or T cell chimerism. Low donor chimerism early after RIC HSCT is an independent risk factor for relapse and impaired survival. Donor chimerism assessment early after RIC HSCT can prognosticate for long-term outcomes and help identify high-risk patient cohorts who may benefit from additional therapeutic interventions.     

Early Lymphocyte Recovery Predicts Superior Survival after Autologous Stem Cell Transplantation in Non-Hodgkin Lymphoma: A Prospective Study

Day 15 absolute lymphocyte count (ALC-15) after autologous peripheral blood hematopoietic stem cell transplantation (APHSCT) has been reported to be a significant predictor for survival in multiple hematologic malignancies. Limitations of previous reports included their retrospective nature and the lack of ALC-15 lymphocyte subset analyses. To address these limitations, from February 2002 until February 2007, 50 non-Hodgkin lymphoma (NHL) patients were enrolled in a prospective study. The primary endpoint of the study was to confirm prospectively the ALC-15 survival role after APHSCT in NHL. The secondary endpoint was to identify the ALC-15 lymphocyte subset affecting survival after APHSCT. With a median follow-up of 22.2 months (range: 6-63.7 months), patients with an ALC-15 ≥500 cells/μL (n = 35) experienced superior overall survival (OS) and progression-free survival (PFS) compared with those who did not; median OS: not reached versus 5.4 months, 3-year OS rates of 80% (95% confidence interval [CI]: 55%-95%) versus 37% (95% CI: 15%-65%), P < .0001; and median PFS: not reached versus 3.3 months, 3-year PFS rates of 63% (95% CI: 40%-85%) versus 13% (95% CI: 4%-40%), P < .0001, respectively. Univariately, CD16⁺/56⁺/CD3⁻ natural killer (NK) cells were the only ALC-15 lymphocyte subset identified as a predictor for survival. Patients with an NK cell count ≥80 cells/μL (n = 38) experienced superior OS and PFS compared with those who did not (median OS: not reached versus 5 months, 3-year OS rates of 76% [95% CI: 57%-92%] versus 36% [95% CI: 11%-62%], P < .0001; and median PFS: not reached versus 3 months, 3-year PFS rates of 57% [95% CI: 38%-85%] versus 9% [95% CI: 1%-41%], P < .0001, respectively). Multivariate analysis showed that NK cells are an independent predictor for survival. This is the first study confirming the ALC-15 survival role prospectively and identifying NK cells as the key ALC-15 lymphocyte subset affecting survival after APHSCT.     

Impact of Donor Source on Allogeneic Hematopoietic Stem Cell Transplantation for Mature T Cell and Natural Killer Cell Neoplasms in the Kyoto Stem Cell Transplantation Group

Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the key strategy to cure patients with mature T and natural killer (NK) cell lymphomas/leukemia, especially those with relapsed/refractory diseases, there is no consensus strategy for donor selection. We retrospectively analyzed the outcomes of allo-HSCT in 111 patients in 15 Japanese institutions as a multi-institutional joint research project. Thirty-nine patients received bone marrow or peripheral blood stem cell transplantation from related donors (rBMT/rPBSCT), 37 received BMT/PBSCT from unrelated donors (uBMT/uPBSCT), and 35 received cord blood transplantation (CBT). Overall survival (OS) and progression-free survival (PFS) at 4 years were 42% and 34%, respectively. The cumulative incidences of relapse and nonrelapse mortality were 43% and 25%. In multivariate analysis, CBT showed comparable OS with rBMT/rPBSCT (rBMT/rPBSCT versus CBT: hazard ratio [HR], 1.63; P = .264) and better OS compared with uBMT/uPBSCT (HR, 2.99; P = .010), with a trend toward a lower relapse rate (rBMT/rPBSCT versus CBT: HR, 2.60; P = .010; uBMT/uPBSCT versus CBT: HR, 2.05; P = .082). This superiority of CBT was more definite in on-disease patients (OS: rBMT/rPBSCT versus CBT: HR, 5.52; P = .021; uBMT/uPBSCT versus CBT: HR, 6.80; P = .007). Better disease control was also strongly associated with better OS and PFS with lower relapse rate. In conclusion, allo-HSCT is beneficial for the survival of patients with mature T and NK cell lymphomas/leukemia if performed in a timely fashion. Since CBT showed favorable survival with a lower relapse risk, it could be a preferred alternative, especially in on-disease patients.     

Autologous Is Superior to Allogeneic Hematopoietic Cell Transplantation for Acute Promyelocytic Leukemia in Second Complete Remission

To identify favored choice of transplantation in patients with acute promyelocytic leukemia (APL) in second complete remission, we studied 294 patients with APL in second complete remission (CR2) receiving allogeneic (n = 232) or autologous (n = 62) hematopoietic cell transplantation (HCT) reported to the Center for International Blood and Marrow Transplantation Research (CIBMTR) from 1995 to 2006, including 155 with pre-HCT PML/RAR∝ status (49% of allogeneic and 66% of autologous). Patient characteristics and transplantation characteristics, including treatment-related mortality, overall survival (OS), and disease-free survival, were collected and analyzed for both univariate and multivariate outcomes. With median follow-up of 115 (allogeneic) and 72 months (autologous), 5-year disease-free survival (DFS) favored autologous with 63% (49% to 75%), compared with allogeneic at 50% (44% to 57%) (P = .10). OS was 75% (63% to 85%) versus 54% (48% to 61%) (P = .002), for autologous and allogeneic transplantation, respectively. Multivariate analysis showed significantly worse DFS after allogeneic HCT (hazard ratio [HR], 1.88; 95% confidence interval [CI], 1.16 to 3.06; P = .011) and age > 40 years (HR, 2.30; 95% CI, 1.44 to 3.67; P = .0005). OS was significantly worse after allogeneic HCT (HR, 2.66; 95% CI, 1.52 to 4.65; P = .0006); age > 40 (HR, 3.29; 95% CI, 1.95 to 5.54; P < .001), and first complete remission < 12 months (HR, 1.56; 95% CI, 1.07 to 2.26; P = .021). Positive pre-HCT PML-RAR∝ status in 17 of 114 allogeneic and 6 of 41 receiving autologous transplantation did not influence relapse, treatment failure, or survival in either group. The survival advantage for autografting was attributable to increased treatment-related mortality (TRM) in the allogeneic group of 30% compared to 2% in the autologous group, in addition to the added mortality associated with GVHD. We conclude that autologous HCT yields superior OS for APL in CR2. Long-term DFS in autologous recipients, even with minimal residual disease–positive grafts, remains an important subject for further study.     

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.     

Specific Features Identify Patients with Relapsed or Refractory Mantle Cell Lymphoma Benefitting from Autologous Hematopoietic Cell Transplantation

Outcomes with autologous hematopoietic cell transplantation (auto HCT) for relapsed and/or refractory mantle cell lymphoma (MCL) are typically poor. We hypothesized that certain factors could predict which patients experience a favorable outcome with this approach. We thus developed a predictive score from a cohort of 67 such patients using 3 factors independently associated with progression-free survival (PFS): (1) simplified Mantle Cell Lymphoma International Prognostic Index score before auto HCT (hazard ratio [HR], 2.9; P = .002); (2) B symptoms at diagnosis (HR, 2.7; P = .005); and (3) remission quotient, calculated by dividing the time, in months, from diagnosis to auto HCT by the number of prior treatments (HR, 1.4; P = .02). The estimated 5-year PFS for favorable-risk patients (n = 23) and unfavorable-risk patients (n = 44) were 58% (95% confidence interval [CI], 34% to 75%) and 15% (95% CI, 6% to 28%), respectively. These factors also independently predicted overall survival. In summary, we have defined 3 simple factors that can identify patients with relapsed/refractory MCL who derive a durable benefit from salvage auto HCT.     

A Comparison of Bronchoalveolar Lavage versus Lung Biopsy in Pediatric Recipients after Stem Cell Transplantation

Bronchoalveolar lavage (BAL) has been a useful initial diagnostic tool in the evaluation of pulmonary complications after hematopoietic stem cell transplantation (HSCT); however, the diagnostic sensitivity, prevalence, and outcome after BAL versus lung biopsy (LB) in pediatric HSCT patients remains to be determined. We reviewed 193 pediatric HSCT recipients who underwent a total of 235 HSCTs. Sixty-five patients (34%) underwent a total of 101 BALs for fever, respiratory distress, and/or pulmonary infiltrates on chest radiograph and/or computed tomography scan. The 1-year probability of undergoing BAL was 43.0% after allogeneic stem cell transplantation (alloSCT) and 8.5% after autologous stem cell transplantation (autoSCT) (P = .001). Sixteen of the 193 patients (8%) patients underwent 19 LBs. The probability of undergoing LB at 1 year after HSCT was 9.3%. No grade III or IV adverse events related to either procedure were observed. Of the 101 BALs performed, 40% (n = 40) were diagnostic, with a majority revealing a bacterial pathogen. Among the 19 LBs performed, 94% identified an etiology. In multivariate analysis, myeloablative conditioning alloSCT conferred the highest risk of requiring a BAL (hazard ratio [HR],8.5; P = .0002). The probability of 2-year overall survival was 20.2% in patients who underwent BAL, 17.5% for patients who underwent biopsy, and 67.4% for patients who had neither procedure. In multivariate analysis, only the requirement of a BAL was independently associated with an increased risk of mortality (HR, 2.96; P < .0001). In summary, in this cohort of pediatric HSCT recipients, BAL and LB were used in approximately 35% and 8% of pediatric HSCTs with diagnostic yields of approximately 40% and 94%, respectively, and were both associated with poor long-term outcomes.     

Clinical Outcomes after Allogeneic Hematopoietic Stem Cell Transplantation in Children with Juvenile Myelomonocytic Leukemia: A Report from the Japan Society for Hematopoietic Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for juvenile myelomonocytic leukemia (JMML), but few large studies of HSCT for JMML exist. Using data from the Japan Society for Hematopoietic Cell Transplantation registry, we analyzed the outcomes of 129 children with JMML who underwent HSCT between 2000 and 2011. The 5-year overall survival (OS) rate and cumulative incidence of relapse were 64% and 34%, respectively. A regimen of busulfan/fludarabine/melphalan was the most commonly used (59 patients) and provided the best outcomes; the 5-year OS rate reached 73%, and the cumulative incidences of relapse and transplantation-related mortality were 26% and 9%, respectively. In contrast, the use of the irradiation-based myeloablative regimen was the most significant risk factor for OS (hazard ratio [HR], 2.92; P = .004) in the multivariate model. In addition, chronic graft-versus-host disease (GVHD) was strongly associated with lower relapse (HR, 0.37; P = .029) and favorable survival (HR, 0.22; P = .006). The current study has shown that a significant proportion of children with JMML can be cured with HSCT, especially those receiving the busulfan/fludarabine/melphalan regimen. Based on the lower relapse and better survival observed in patients with chronic GVHD, additional treatment strategies that focus on enhancing graft-versus-leukemia effects may further improve survival.     

Infused Autograft Lymphocyte to Monocyte Ratio and Survival in Diffuse Large B Cell Lymphoma

Infused autograft absolute lymphocyte count is a prognostic factor for survival after autologous peripheral hematopoietic stem cell transplantation (APHSCT) for diffuse large B cell lymphoma (DLBCL). CD14⁺ HLA-DR^low/neg immunosuppressive monocytes affect tumor growth by suppressing host antitumor immunity. Thus, we set out to investigate if the infused autograft lymphocyte to monocyte ratio (A-LMR), as a biomarker of host immunity (ie, lymphocytes) and immunosuppression (ie, monocytes), affects survival after APHSCT. From 1994 to 2012, 379 DLBCL patients who underwent APHSCT were studied. The 379 patients were randomly divided into a training set (n = 253) and a validation set (n = 126). Receiver operating characteristic and area under the curve identified an A-LMR ≥1 as the best cut-off value, which was validated by the k-fold cross-validation in the training set. Multivariate analysis showed A-LMR to be an independent prognostic factor for survival in the training set. Patients with an A-LMR ≥ 1.0 experienced superior overall survival (OS) compared with patients with an A-LMR <1.0 (median OS: 167.2 versus 17.6 months; 5-year OS: 73% [95% confidence interval (CI), 63% to 80%] versus 30% [95% CI, 2% to 38%], P < .0001, respectively) in the training set. In the validation set, an A-LMR ≥ 1 showed a median OS of 181.2 months versus 19.5 months for an A-LMR <1, and 5-year OS rates of 67% (95% CI, 52% to 79%) versus 35% (95% CI, 25% to 47%), P < .0001, respectively. The A-LMR provides a platform to engineer immunocompetent autograft to improve clinical outcomes in DLBCL patients undergoing APHSCT.     

Early Failure of Frontline Rituximab-Containing Chemo-immunotherapy in Diffuse Large B Cell Lymphoma Does Not Predict Futility of Autologous Hematopoietic Cell Transplantation

The poor prognosis for patients with diffuse large B cell lymphoma (DLBCL) who relapse within 1 year of initial diagnosis after first-line rituximab-based chemo-immunotherapy has created controversy about the role of autologous transplantation (HCT) in this setting. We compared autologous HCT outcomes for chemosensitive DLBCL patients between 2000 and 2011 in 2 cohorts based on time to relapse from diagnosis. The early rituximab failure (ERF) cohort consisted of patients with primary refractory disease or those with first relapse within 1 year of initial diagnosis. The ERF cohort was compared with those relapsing >1 year after initial diagnosis (late rituximab failure [LRF] cohort). ERF and LRF cohorts included 300 and 216 patients, respectively. Nonrelapse mortality (NRM), progression/relapse, progression-free survival (PFS), and overall survival (OS) of ERF versus LRF cohorts at 3 years were 9% (95% confidence interval [CI], 6% to 13%) versus 9% (95% CI, 5% to 13%), 47% (95% CI, 41% to 52%) versus 39% (95% CI, 33% to 46%), 44% (95% CI, 38% to 50%) versus 52% (95% CI, 45% to 59%), and 50% (95% CI, 44% to 56%) versus 67% (95% CI, 60% to 74%), respectively. On multivariate analysis, ERF was not associated with higher NRM (relative risk [RR], 1.31; P = .34). The ERF cohort had a higher risk of treatment failure (progression/relapse or death) (RR, 2.08; P < .001) and overall mortality (RR, 3.75; P < .001) within the first 9 months after autologous HCT. Beyond this period, PFS and OS were not significantly different between the ERF and LRF cohorts. Autologous HCT provides durable disease control to a sizeable subset of DLBCL despite ERF (3-year PFS, 44%) and remains the standard-of-care in chemosensitive DLBCL regardless of the timing of disease relapse.     

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.     

Analysis of Donor and Recipient ABO Incompatibility and Antibody-Associated Complications after Allogeneic Stem Cell Transplantation with Reduced-Intensity Conditioning

Allogeneic hematopoietic stem cell transplantation (HSCT) can be performed across the ABO blood group barrier. The impact of ABO incompatibility on clinical outcome is controversial. A retrospective analysis of 310 patients who underwent HSCT with reduced-intensity conditioning between 1998 and 2011 was performed to investigate the frequency and clinical implications of anti-RBC antibodies in passenger lymphocyte syndrome (PLS) after minor ABO mismatch (mm), persistent or recurring recipient type ABO antibodies (PRABO) after major ABO mm HSCT, and autoimmune hemolytic anemia (AIHA). Transplantation characteristics and clinical outcome were analyzed by univariate and multivariate analysis for groups with or without anti-RBC antibodies. ABO blood group incompatibility did not affect clinical outcome despite an increased requirement of blood transfusion. Twelve patients with AIHA, 6 patients with PLS, and 12 patients with PRABO post-HSCT were identified. AIHA did not affect overall survival (OS) or transplant-related mortality (TRM), but patients with AIHA had a lower incidence of grades II to IV acute graft-versus-host disease (P = .05). OS in the PLS group was 0% compared with 61% in the whole group receiving minor ABO mm transplants (P < .001). Comparing PRABO patients with those receiving a major ABO mm HSCT, the OS was 17% versus 73% (P = .002) and TRM was 50% versus 21% (P = .03). At our center, PLS after minor ABO mm and PRABO antibodies after major ABO mm HSCT are significant risk factors for decreased OS and TRM. Our results suggest that occurrence of unexpected ABO antibodies after HSCT warrant a wider investigation individual to find the underlying cause.     

Phase I Trial of Maintenance Sorafenib after Allogeneic Hematopoietic Stem Cell Transplantation for Fms-like Tyrosine Kinase 3 Internal Tandem Duplication Acute Myeloid Leukemia

The fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) mutation is associated with a high relapse rate for patients with acute myeloid leukemia (AML) even after allogeneic hematopoietic stem cell transplantation (HSCT). Sorafenib is a tyrosine kinase inhibitor, which inhibits the FLT3 tyrosine kinase and has shown encouraging activity in FLT3-ITD AML. We conducted a phase I trial of maintenance sorafenib after HSCT in patients with FLT3-ITD AML (ClinicalTrials.gov NCT01398501). Patients received a variety of conditioning regimens and graft sources. A dose escalation 3 + 3 cohort design was used to define the maximum tolerated dose (MTD), with an additional 10 patients treated at the MTD. Sorafenib was initiated between days 45 and 120 after HSCT and continued for 12 28-day cycles. Twenty-two patients were enrolled (status at HSCT: first complete remission [CR1], n = 16; second complete remission [CR2], n = 3; refractory, n = 3). The MTD was established at 400 mg twice daily with 1 dose-limiting toxicity (DLT) observed (pericardial effusion). Two patients died of transplantation-related causes, both unrelated to sorafenib. Two patients stopped sorafenib after relapse and 5 stopped because of attributable toxicities after the DLT period. Median follow-up for surviving patients is 16.7 months after HSCT (range, 8.1 to 35.0). There was 1 case of grade II acute graft-versus-host disease (GVHD) after starting sorafenib and the 12-month cumulative incidence of chronic GVHD was 38% (90% confidence interval [CI], 21% to 56%). For all patients, 1-year progression-free survival (PFS) was 85% (90% CI, 66% to 94%) and 1-year overall survival (OS) was 95% (90% CI, 79% to 99%) after HSCT. For patients in CR1/CR2 before HSCT (n = 19), 1-year PFS was 95% (90% CI, 76% to 99%) and 1-year OS was 100%, with only 1 patient who relapsed. Sorafenib is safe after HSCT for FLT3-ITD AML and merits further investigation for the prevention of relapse.     

Donor Selection for Killer Immunoglobulin-like Receptors B Haplotype of the Centromeric Motifs Can Improve the Outcome after HLA-Identical Sibling Hematopoietic Stem Cell Transplantation

After hematopoietic stem cell transplantation (HSCT), natural killer (NK) cell alloreactivity in HLA cells of recipients is regulated by killer immunoglobulin-like receptors (KIRs) on donor NK cells. The effect of KIRs on HSCT outcomes is controversial, particularly in those undergoing HLA-identical sibling HSCT. In this study, effects of KIR and HLA genotypes on the HSCT outcome were investigated in a 5-year retrospective study comprising 219 patient-donor pairs undergoing HLA-identical sibling HSCT for myeloid and lymphoid malignancies. We found that 39.7% (87 of 219) of these pairs, which were KIR mismatched, had better overall survival (OS) and reduced grade III to IV acute graft-versus-host disease (aGVHD), especially in acute myeloid leukemia (AML) patients. Bx1 donor KIR genotype with haplotype B on a telomeric region was a risk factor for the OS and relapse-free survival (RFS). Donor centromeric (c) and telomeric (t) KIR haplotype analysis showed that donor KIR cB-tA/tB was associated with improved OS and RFS compared with cA-tA or cA-tB. Furthermore, donor KIR B haplotype of the centromeric motifs (Cen-B) was an independent beneficial factor in improving OS and RFS and in protecting from relapse after HSCT. In AML patients, the occurrence of aGVHD was significantly lower in HLA-C1 group compared with that in HLA-C2 group, although such effect was not observed in patients with acute lymphoblastic leukemia or chronic myelogenous leukemia. Our results suggest that KIR could impact outcome and donor KIR haplotype with Cen-B confer significant survival benefits to HLA-identical sibling HSCT.     

Impact of Thrombotic Microangiopathy on Renal Outcomes and Survival after Hematopoietic Stem Cell Transplantation

Transplantation-associated thrombotic microangiopathy (TA-TMA) is a serious complication of hematopoietic stem cell transplantation (HSCT). We characterized the incidence, risk factors, and long-term outcomes associated with TA-TMA by performing a comprehensive review of all adult patients (n?=?1990) undergoing allogeneic HSCT at the Dana Farber Cancer Institute/Brigham and Women's Hospital between 2005 and 2013. Using the City of Hope criteria, we identified 258 patients (13%) with “definite” TMA and 508 patients (26%) with “probable” TMA. Mismatched donor transplantation (subdistribution hazard ratio [sHR], 1.79; 95% confidence interval [CI], 1.17 to 2.75; P?=?.007), sirolimus-containing graft-versus-host disease prophylaxis (sHR, 1.73; 95% CI, 1.29 to 2.34; P?<?.001), myeloablative conditioning (sHR, 1.93, 95% CI, 1.38 to 2.68; P?<?.001), and high baseline lactate dehydrogenase (LDH) level (sHR, 1.64; 95% CI, 1.26 to 2.13; P?<?.001) were associated with definite TMA. Moreover, positive cytomegalovirus serostatus (sHR, 1.41; 95% CI, 1.16 to 1.71; P?<?.001), high and very high disease risk index (sHR, 1.48; 95% CI, 1.12 to 1.96, P?=?.007), and high baseline LDH level (sHR, 1.25; 95% CI, 1.05 to 1.49; P?=?.011) were associated with probable TMA. In multivariable analyses, definite and probable TMA were each independently associated with higher mortality (HR, 5.24; 95% CI, 4.43 to 6.20 and HR, 2.12; 95% CI, 1.84 to 2.44, respectively), and long-term kidney dysfunction (HR, 5.43; 95% CI, 4.61 to 6.40 and HR, 2.20; 95% CI, 1.92 to 2.51, respectively). Definite and probable TMA were also independently associated with an increased risk of nonrelapse mortality and shorter progression-free survival. Our findings indicate that TA-TMA is common following HSCT and is independently associated with increased risk of death and kidney dysfunction.     

The Graft-Versus-Myeloma Effect: Chronic Graft-Versus-Host Disease but Not Acute Graft-Versus-Host Disease Prolongs Survival in Patients with Multiple Myeloma Receiving Allogeneic Transplantation

We conducted a study of patients with multiple myeloma (MM) undergoing allogeneic transplantation to evaluate outcome parameters. Fifty-seven consecutive patients with MM received an allogeneic transplantation between 2004 and 2011 at our institution. Patients who had received at least 1 prior autologous transplantation were included. Twenty-six patients underwent allogeneic transplantation for consolidation after a response to their first autograft, and 30 patients received an allogeneic transplantation as salvage therapy. Donor source was evenly distributed between related and unrelated. The median follow-up was 52 months. Thirty-two (57.1%) patients achieved a complete response (CR). At 5 years, 49.2% of all patients were in CR. Sixteen patients received either donor lymphocyte infusions or immune suppression withdrawal for disease progression, with a 62.5% response rate. The 5-year overall survival (OS) for all patients was 59%. The 5-year OS for the 30 patients in the consolidation group was 82% compared with 38% for those in the salvage group. In multivariate analysis, 3 factors remained significantly associated with OS. These include being in the salvage group (hazard ratio [HR], 4.05; P = .0196), acute graft-versus-host disease (aGVHD) (HR, 2.99; P = .034), and chronic graft-versus-host disease (cGVHD), which was highly protective, with a 5-year OS of 78.8% for patients with cGVHD versus 42.6% for patients without cGVHD (HR .17, P = .008). Our data show that allogeneic transplantation for MM can lead to sustained remissions. aGVHD is significantly deleterious to OS and progression-free survival, whereas cGVHD is strongly favorable, supporting an important role for the graft-versus-myeloma effect.     

Autologous Hematopoietic Stem Cell Transplantation in Extranodal Natural Killer/T Cell Lymphoma: A Multinational,Multicenter, Matched Controlled Study

Extranodal natural killer (NK)/T cell lymphoma, nasal type, is a recently recognized distinct entity and the most common type of non–B cell extranodal lymphoma in Asia. This retrospective analysis studied the potential survival benefits of hematopoeitic stem cell transplantation (HSCT) compared with a historical control group. A total of 47 patients from 3 previously published series of HSCT were matched according to NK/T cell lymphoma International Prognostic Index (NKIPI) risk groups and disease status at transplantation with 107 patients from a historical control group for analysis. After a median follow-up of 116.5 months, the median survival time was not determined for the HSCT group, but it was 43.5 months for the control group (95% confidence interval [CI] = 6.7 to 80.3 months; P = .127, log-rank test). In patients who were in complete remission (CR) at the time of HSCT or at surveillance after remission, disease-specific survival rates were significantly higher in the HSCT group compared with the control group (disease-specific 5-year survival rate, 87.3% for HSCT vs 67.8% for non-HSCT; P = .027). In contrast, in subgroup analysis on non-CR patients at the time of HSCT or non-HSCT treatment, disease-specific survival rates were not significantly prolonged in the HSCT group compared with the control group (1-year survival rate, 66.7% for HSCT vs 28.6% for non-HSCT; P = .141). The impact of HSCT on the survival of all patients was significantly retained at the multivariate level with a 2.1-fold (95% CI =1.2- to 3.7-fold) reduced risk of death (P = .006). HSCT seems to confer a survival benefit in patients who attained CR on postremission consolidation therapy. These findings suggest that, in particular, patients in CR with high NKIPI risk scores at diagnosis should receive full consideration for HSCT.     

Effects of the NK Cell Recovery on Outcomes of Unmanipulated Haploidentical Blood and Marrow Transplantation for Patients with Hematologic Malignancies

The goal of this study was to investigate the association of natural killer (NK) cell recovery with clinical outcomes after unmanipulated haploidentical blood and marrow transplantation. We sequentially monitored the reconstitution kinetics of circulating NK cells, CD56^bright and CD56^dim, in 43 patients by flow cytometry, and the functionality recovery of cytokine or cytotoxicity of NK cells by flow cytometry or lactate dehydrogenase release assay after transplantation. Reconstitution of NK cells was rapid but accompanied by skewing of cell subsets mainly in CD56^bright, which recovered earlier. Linear regression analysis demonstrated that dose of CD34⁺ cells in the allografts was inversely correlated with the ratio of T/NK cells (β = −0.506, P = .003) and CD56^dim/CD56^bright cell (β = −.403, P = .018) by day 14 after hematopoietic stem cell transplantation (HSCT), and the dose of CD3⁺ T cells in the allografts was also inversely correlated with the ratio CD56^dim/CD56^bright cells by day 14 after HSCT (β = −0.474, P = .005). Moreover, the dose of CD56^dim NK cells in the allograft was positively associated with the day 14 CD56^brigh NK cells (β = 0.494, P = .032) and inversely correlated with the day 14 ratio of CD56^dim/CD56^bright cells (β = −0.617, P = .005). Compared with nonacute graft-versus-host disease (GVHD) patients, patients with acute GVHD (aGVHD) had a higher level of NK subsets during week 2 posttransplantation. Cox regression analysis revealed that the patients with more CD56^bright NK cells in the recovery stage had a higher survival rate (hazard risk [HR], 0.406; P = .017) and the patients with a higher ratio of T/NK (>1.0) had a higher chance of getting aGVHD (HR, 3.436; P = .059) and chronic GVHD (HR, 3.925; P = .028). Our results suggest that the recovery of NK cells is and can be used as an indicator to predicate the clinical outcomes after unmanipulated haploidentical transplantation.     

Long-Term Follow-Up of a Donor versus No-Donor Comparison in Patients with Multiple Myeloma in First Relapse after Failing Autologous Transplantation

We report the long-term clinical outcomes of a retrospective multicenter study that enrolled 169 patients with multiple myeloma (MM) in first relapse after failing autologous stem cell transplantation (SCT). After HLA typing at relapse, 79 patients with a suitable donor, 72 (91%) of whom eventually underwent salvage allogeneic SCT (allo-SCT), were compared with 90 patients without a donor who were treated with multiple lines of salvage treatment with bortezomib and/or immunomodulatory agents. At a median follow-up of 30 months (range, 2-180 months) for all patients and 110 months (range, 38-180 months) for surviving patients, 7-year progression-free survival (PFS) was 18% in the donor group and 0% in the no-donor group (hazard ratio [HR], 2.495; 95% confidence interval [CI], 1.770-3.517; P?<?.0001). Seven-year overall survival (OS) was 31% in the donor group and 9% in the no-donor group (HR, 1.835; 95% CI, 1.306-2.577; P?<?.0001). By multivariate analysis, chemosensitivity to salvage treatments and presence of a suitable donor were significantly associated with better PFS and OS. The long-term follow-up of this study confirms the significant PFS benefit and provides new evidence of an OS advantage for patients with MM who have a suitable donor and undergo allo-SCT. Allo-SCT should be considered as a treatment option in young relapsed patients with high-risk disease features after first-line treatment.