Myeloablative Hematopoietic Stem Cell Transplantation Research Articles

Early hematopoietic stem cell transplant is associated with favorable outcomes in children with MDS

Although hematopoietic stem cell transplantation (HSCT) is the treatment of choice for childhood myelodysplastic syndrome (MDS), there is no consensus regarding patient or disease characteristics that predict outcomes. We reviewed 37 consecutive pediatric MDS patients who received myeloablative HSCT between 1990 and 2010 at a single center. Twenty had primary MDS and 17 had secondary MDS. Diagnostic cytogenetics included monosomy 7 (n = 21), trisomy 8 (n = 7) or normal/other (n = 8). According to the modified WHO MDS classification, thirty had refractory cytopenia and seven had refractory anemia with excess blasts. IPSS scores were: low risk (n = 1), intermediate-1 (n = 15), and intermediate-2 (n = 21). OS and DFS at 10 years in the entire cohort was 53% and 45%. Relapse at 10 years was 26% and 1 year TRM was 25%. In multivariate analysis, factors associated with improved 3 years DFS were not receiving pre-HSCT chemotherapy (RR = 0.30, 95% CI 0.10-0.88; P = 0.03) and a shorter interval (<140 days) from time of diagnosis to transplant (RR = 0.27, 95% CI 0.09-0.80; P = 0.02). Three years DFS in patients who did not receive pre-HSCT chemotherapy and those who had a shorter interval to transplant (n = 16) was 80%. These results suggest that children with MDS should be referred for allogeneic HSCT soon after diagnosis and that pre-HSCT chemotherapy does not appear to improve outcomes.

Prognostic Impact of Posttransplantation Iron Overload after Allogeneic Stem Cell Transplantation

In patients referred for allogeneic hematopoietic stem cell transplantation (HSCT), iron overload is frequent and associated with increased morbidity and mortality. Both the evolution of iron overload after transplantation and its correlation with late posttransplantation events are unknown. We studied 290 patients undergoing myeloablative allogeneic HSCT between 2000 and 2009. Serum ferritin, transferrin saturation, transferrin, iron, and soluble transferrin receptor were determined regularly between 1 and 60 months after HSCT, and values were correlated with transplantation outcome. Ferritin levels peaked in the first 3 months posttransplantation and then decreased to normal values at 5 years. Transferrin saturation and iron behaved analogously, whereas transferrin and soluble transferrin receptor increased after an early nadir. Landmark survival analysis showed that hyperferritinemia had a detrimental effect on survival in all periods analyzed (0 to 6 months P < .001; 6 to 12 months P < .001; 1 to 2 years P = .02; 2 to 5 years P = .002). This effect was independent of red blood cell transfusion dependency and graft-versus-host disease. Similar trends were seen for other iron parameters. These data show the natural dynamics of iron parameters in the setting of allogeneic HSCT and provide evidence for a prognostic role of iron overload extending beyond the immediate posttransplantation period. Interventions to reduce excessive body iron might therefore be beneficial both before and after HSCT.

Adenovirus Viremia and Disease: Comparison of T Cell–Depleted and Conventional Hematopoietic Stem Cell Transplantation Recipients from a Single Institution

Adenovirus (ADV) is an important cause of viral mortality in hematopoietic stem cell transplantation (HSCT). Recipients of T cell–depleted (TCD) HSCT are at increased risk for viral infections. We compared the rates and outcomes of ADV viremia and disease between TCD and conventional (CONV) HSCT at our institution. This was an observational study of 624 adult and pediatric recipients of myeloablative HSCT at Memorial Sloan-Kettering Cancer Center between January 1, 2006, and March 11, 2011. Viral cultures and ADV PCR were ordered as clinically indicated. ADV viremia by quantitative PCR assay was defined as 1 or more positive values ≥1,000 copies/mL or 2 or more consecutive positive values. Competing-risk regression analyses were used to identify predictors for ADV viremia. ADV viremia at 1 year after HSCT occurred in 8% of TCD HSCT recipients and in 4.0% of CONV HSCT recipients (P = .041). Among the TCD recipients, ADV viremia was seen in 15% of children, compared with 5% of adults (P = .008). Young age (hazard ratio [HR], 3.0; P < .001) and acute graft-versus-host disease (GVHD) (HR, 3.2; P = .001) were identified as risk factors for ADV viremia. ADV viremia was predictive of mortality (HR, 6.0; P < .001). ADV disease developed in 3.5% of TCD HSCT recipients and in 0.4% of CONV HSCT recipients (P = .022), with an attributable mortality of 27%. Among TCD HSCY recipients, grade II to IV GVHD was a risk factor for ADV disease (HR, 13; P < .001), but age was not. More than 90% of the cases of ADV disease involved a viral load of ≥10,000 copies/mL. Rates of ADV disease were 10-fold greater in TCD HSCT recipients compared with CONV HSCT recipients, predominantly in patients who developed acute GVHD. The benefit of preemptive therapy for an ADV viral load ≥10,000 copies/mL for preventing ADV disease in TCD HSCT recipients should be evaluated in prospective clinical trials.

Promising Role of Reduced-Toxicity Hematopoietic Stem Cell Transplantation (PART-I)

Allogeneic hematopoietic stem cell transplantation (HSCT) remains a potential curative option for many patients with hematological malignancies (HM). However, the high rate of transplantation-related mortality (TRM) restricted the use of standard myeloablative HSCT to a minority of young and fit patients. Over the past few years, it has become evident that the alloreactivity of the immunocompetent donor cells mediated anti-malignancy effects independent of the action of high dose chemoradiotherapy. The use of reduced intensity conditioning (RIC) regimens has allowed a graft-versus-malignancy (GvM) effect to be exploited in patients who were previously ineligible for HSCT on the grounds of age and comorbidity. Retrospective analysis showed that RIC has been associated with lower TRM but a higher relapse rate leading to similar intermediate term overall and progression-free survivals when compared to standard myeloablative HSCT. However, the long term antitumor effect of this approach is less well established. Prospective studies are ongoing to define which patients might most benefit from reduced toxicity stem cell transplant (RT-SCT) and which transplant protocols are suitable for the different types of HM. The advent of RT-SCT permits the delivery of a potentially curative GvM effect to the majority of patients with HM whose outcome with conventional chemotherapy would be dismal. Remaining challenges include development of effective strategies to reduce relapse rates by augmenting GvM effects without increasing toxicity.

Does iron overload really matter in stem cell transplantation?

A growing body of evidence suggests that iron overload is associated with inferior outcomes after myeloablative allogeneic hematopoietic stem cell transplantation (HSCT). However, all of those studies used surrogate markers of iron overload, especially serum ferritin, and most had a retrospective design. We conducted a prospective observational study in patients with myelodysplastic syndrome or acute leukemia undergoing myeloablative HSCT. Forty-five patients who were followed for over 1 year, with serial measurements of serum iron parameters, as well as liver and cardiac magnetic resonance imaging. There was no significant increase in ferritin, liver or cardiac iron content in the 12 months following HSCT. Although serum ferritin still appeared to have prognostic significance, as previously reported, pre-HSCT iron overload (as reflected in liver iron content) was not associated with increased mortality, relapse, or graft-versus-host disease. These results raise the possibility that the adverse prognostic impact of pre-HSCT hyperferritinemia may be related to factors independent of iron overload.

Association of IL-1β −511 Polymorphism With Severe Veno-occlusive Disease in Pediatric-matched Allogeneic Hematopoietic Stem Cell Transplantation

Single nucleotide polymorphisms (SNPs) of the interleukin 1 (IL-1) family have been implicated in acute graft-versus-host disease and mortality postallogeneic hematopoietic stem cell transplantation (HSCT) in adults. Hepatic veno-occlusive disease (VOD) is a well-known complication of HSCT and can result in an increased risk of mortality. In this study, we sought to investigate the association of both patient and donor genotypes at the IL-1β -511 cytidine/thymidine (C/T) polymorphic site with hepatic VOD and mortality in an exclusive pediatric cohort undergoing matched myeloablative allogeneic HSCT. Donor TT genotype was associated with higher cumulative incidence of grade III-IV hepatic VOD at 3 months after transplantation relative to donor CT and CC genotypes (25±13.1% in TT, 2.9±2.9% in CT, and 3.6±3.6% in CC; P=0.024). Neither recipient nor donor IL-1β -511 single nucleotide polymorphisms genotypes were associated with mortality or relapse. Our findings suggest that donor, rather than host, genotype at the IL-1β -511 polymorphic site may associate with higher risk for severe VOD after matched allogeneic HSCT. Our findings challenge the assumption that host factors are exclusively responsible for VOD and suggest a novel role for the donor inflammasome pathway in inducing injury and microvascular disease after HSCT, which merits further study in a larger cohort analysis.

Novel myeloma-associated antigens revealed in the context of syngeneic hematopoietic stem cell transplantation

AbstractTargets of curative donor-derived graft-versus-myeloma (GVM) responses after allogeneic hematopoietic stem cell transplantation (HSCT) remain poorly defined, partly because immunity against minor histocompatibility Ags (mHAgs) complicates the elucidation of multiple myeloma (MM)–specific targets. We hypothesized that syngeneic HSCT would facilitate the identification of GVM-associated Ags because donor immune responses in this setting should exclusively target unique tumor Ags in the absence of donor-host genetic disparities. Therefore, in the present study, we investigated the development of tumor immunity in an HLA-A0201+ MM patient who achieved durable remission after myeloablative syngeneic HSCT. Using high-density protein microarrays to screen post-HSCT plasma, we identified 6 Ags that elicited high-titer (1:5000-1:10 000) Abs that correlated with clinical tumor regression. Two Ags (DAPK2 and PIM1) had enriched expression in primary MM tissues. Both elicited Ab responses in other MM patients after chemotherapy or HSCT (11 and 6 of 32 patients for DAPK2 and PIM1, respectively). The index patient also developed specific CD8+ T-cell responses to HLA-A2–restricted peptides derived from DAPK2 and PIM1. Peptide-specific T cells recognized HLA-A2+ MM-derived cell lines and primary MM tumor cells. Coordinated T- and B-cell immunity develops against MM-associated Ags after syngeneic HSCT. DAPK1 and PIM1 are promising target Ags for MM-directed immunotherapy.

Myeloablative Transplantation using either Cord Blood or Bone Marrow leads to Immune Recovery, High Long-Term Donor Chimerism and Excellent Survival in Chronic Granulomatous Disease

The curative potential of hematopoietic stem cell transplantation in patients with chronic granulomatous disease depends on availability of a suitable donor, successful donor engraftment, and maintenance of long-term donor chimerism. Twelve consecutive children (median age, 59.5 months; range, 8-140 months) with severe chronic granulomatous disease (serious bacterial/fungal infections pretransplantation; median, 3; range, 2-9) received myeloablative hematopoietic stem cell transplantation using sibling bone marrow ([SibBM]; n = 5), unrelated cord blood (UCB; n = 6), and sibling cord blood (n = 1) at our center between 1997 and 2010. SibBM and sibling cord blood were HLA matched at 6/6, whereas UCB were 5/6 (n = 5) or 6/6 (n = 1). Recipients of SibBM were conditioned with busulfan and cyclophosphamide ± anti-thymocyte globulin (ATG), whereas 6 of 7 cord blood recipients received fludarabine/busulfan/cyclophosphamide/ATG. Seven patients received granulocyte-colony stimulating factor-mobilized granulocyte transfusions from directed donors. The first 2 UCB recipients had primary graft failure but successfully underwent retransplantation with UCB. Highest acute graft-versus-host disease was grade III (n = 1). Extensive chronic graft-vs-host disease developed in 3 patients. All patients are alive with median follow-up of 70.5 months (range, 12-167 months) with high donor chimerism (>98%, n = 10; 94%, n= 1; and 92%, n = 1). Myeloablative hematopoietic stem cell transplantation led to correction of neutrophil dysfunction, durable donor chimerism, excellent survival, good quality of life, and low incidence of graft-vs-host disease regardless of graft source.

Evaluation of respiratory conditions in early phase of hematopoietic stem cell transplantation

ObjectivesTo investigate the effectiveness of respiratory physiotherapy based on clinical evidence and analyze the improvement in respiratory parameters.MethodsA prospective study was carried out in the Bone Marrow Transplant Unit of the Universidade Estadual de Campinas (UNICAMP). Two different previously established respiratory physiotherapy protocols were applied from days D-1 to D+7 that aimed to improve airway clearance, pulmonary re-expansion and the strengthening of respiratory muscles. Group A were subjected to diaphragmatic proprioceptive stimulation, breathing exercises, incentive spirometry with Respiron®, inspiratory muscle training with the Threshold® Inspiratory Muscle Training device, bronchial hygienization with Shaker® and cough stimulation. Group B performed a protocol that only used incentive spirometry. The parameters analyzed were: tidal volume, minute volume, maximal inspiratory pressure, maximal expiratory pressure, oxygen saturation, heart rate and respiratory frequency.ResultsSixty-seven patients submitted to myeloablative hematopoietic stem cell transplantation were included in this study. Among these, thirty-nine were evaluated and randomized in the two groups. There were significant differences between the groups for tidal volume at D+2 (p-value = 0.007) and maximal inspiratory pressure (p-value = 0.03), maximal expiratory pressure (p-value = 0.03) and tidal volume (p-value = 0.004) at D+7.ConclusionsOn comparing Group A with Group B, the authors concluded that the protocol of respiratory physiotherapy applied in this study resulted in an improvement in ventilation and in respiratory muscle strength of patients submitted to hematopoietic stem cell transplantation.

Evaluation of respiratory conditions in early phase of hematopoietic stem cell transplantation

The scientific foundation of respiratory therapy (RT) has increased over the last decade in patients with respiratory diseases(1); however, its effect in patients with other diseases remains poorly understood. In this issue of the Revista Brasileira de Hematologia e Hemoterapia, Bom et al.(2) demonstrate the benefits of RT in patients submitted to myeloablative hematopoietic stem cell transplantation (HSCT). The importance of this study is related to the fact that, despite the tremendous benefits that transplantation brings to these patients, they still present a significant risk of chronic and acute complications due to conditioning regimens and immunosuppression, toxicity, infections, graft versus host disease and being bedridden after the transplant. The proposal of Bom et al. was to compare the improvement in ventilatory capacity during the post-transplant period using distinct protocols in patients submitted to HSCT to see whether their respiratory capacity could be improved. This elegant study involved 39 adult patients randomized in 2 groups: A: patients performing incentive spirometry and B: patients receiving incentive spirometry associated with respiratory muscle strengthening and bronchial hygiene techniques. The results clearly show that patients submitted to 7 days of incentive spirometry treatment presented a significantly higher increase in muscle strength and ventilation compared to the group that did not receive this treatment. The results are very relevant and suggest that these patients have a reduction in their respiratory muscle strength and ventilator capacity that is reversed by specific training. Despite these important results, some questions still remain unanswered such as: which patients most benefit from this treatment and whether this treatment reduces post-transplant complications. However, since this group has much research and clinical experience in HSCT patients, I am sure they will answer these questions quite soon.

Importance of functional evaluation after hematopoietic cell transplantation

Substantial advances in hematopoietic stem cell transplantation (HSCT) have been accomplished in the last three decades(1). For example, reductions in early mortality by 60% and in overall mortality by 41% have been achieved in patients transplanted in Seattle after the introduction of high intensity conditioning between 2003 and 2007 compared to the 1993 to 1997 period(2). According to the Center for International Blood and Marrow Transplant Research (CIBMTR), several thousands of long-term HSCT recipients are surviving worldwide from diseases considered fatal before transplantation. Nonetheless, HSCT can result in several complications resulting in impaired quality of life (QoL). Determinants of overall benefits of HSCT therefore are not limited to the eradication of the original disease and improved survival, but also to impairment of QoL with an impact on functional performance. As a matter of fact, several studies of QoL that evaluated mental and physical function, domestic and vocational role function and family and social interaction have reported impairments in functional performance in both autologous and allogeneic HSCT recipients(3-5). In this issue of the Revista Brasileira de Hematologia e Hemoterapia, Souza et al. describe the evaluation of functional performance before and after myeloablative conditioning HSCT in patients transplanted in one center in Brazil(6). Evaluation of functional performance included gait performance, grip strength, spine mobility and function role in daily activities using the Human Activity Profile (HAP) questionnaire. A significant decline in functional performance was found in both autologous and allogeneic HSCT recipients, including in the two-minute walk test (gait performance), grip strength of both hands, spine mobility (Schober test) and daily activities using the maximum and adapted activity score of the HAP. These findings are consistent with studies of North American HSCT populations(3-5). To the best of my knowledge, this is the first prospective study evaluating functional performance in a Brazilian HSCT population. Decline in functional performance depends on several factors including the presence of chronic graft-versus-host disease(5), but the decline in functional performance can improve 5 years after HSCT(3,4). Findings of the current study need to be considered as preliminary because of the small population studied and the relative short follow up. A larger population and longer follow up are needed to confirm the current study findings, and to determine if the decline in functional capacity will improve or result in further performance limitations over time. The study of Souza et al. demonstrates the feasibility of conducting a prospective study of functional performance in recipients of HSCT in Brazil(6). Moreover, it creates an opportunity to conduct larger studies to evaluate risk factors for poor functional performance in transplant recipients in Brazil and to design future intervention studies aimed at improving functional capacity and performance after HSCT.

Fludarabine-Based Reduced Intensity Hematopoietic Stem Cell Transplantation (RIST) for Patients Aged 50–70 Years with Acute Lymphoblastic Leukemia (ALL) in Remission: A Study From the ALL Working Group of the Japan Society for Hematopoietic Cell Transplantation (JSHCT)

Abstract 1935▪▪This icon denotes a clinically relevant abstract Background:Although RIST has become more popular for elderly patients with leukemia, its value for ALL patients is still uncertain. To clarify the clinical significance of RIST for elderly patients with ALL in remission and identify prognostic factors for recipients, we retrospectively surveyed ALL patients receiving RIST who were registered in the JSHCT database. Patients and Methods: This study included ALL patients aged ≥ 50 years who received fludarabine-based RIST as the first transplantation between 2000 and 2009. The preparative regimen was classed as fludarabine-based reduced intensity conditioning if it included non-myeloablative chemotherapy (total dose of busulfan ≤ 8 mg/kg or melphalan ≤ 140 mg/m2) with or without total body irradiation (TBI) ≤ 6 Gy. Results: There were 144 patients, including 118 in first complete remission (CR1) and 26 in CR2. Their median age was 59 years (range: 50–70 years), with 71 males and 73 females. Eighty-seven patients had Philadelphia chromosome-positive ALL. Conditioning regimens contained fludarabine combined with melphalan (n=70), busulfan (n=58), or cyclophosphamide (n=16). TBI plus chemotherapy was used in 90 patients. Bone marrow from related or unrelated donors was transplanted in 71 patients, as well as peripheral blood stem cell from related donors in 31 patients and cord blood in 42 patients. Primary graft failure occurred in 7 patients. Granulocyte and platelet engraftment was achieved after a median of 15 and 26 days, respectively. The incidence of grade II-IV and grade III-IV acute GVHD was 37% and 19%, respectively. After a median follow-up of 16 months (range: 1–83 months), 3-year overall survival (OS) was 53%. The cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) at 3 years was 29% and 31% respectively. According to univariate analysis, factors associated with worse 3-year OS included a high leukocyte count (≥ 30,000 /μl) at diagnosis (vs low leukocyte count: 35% vs 61%, p=0.004), CR2 at transplantation (vs CR1: 30% vs 58%, p=0.014), and grade III-IV acute GVHD (vs grade 0-II: 25% vs 63%, p<0.001). CR2 status (vs CR1: 49% vs 25%, p=0.013) and related donors (vs unrelated donors: 40% vs 24%, p=0.037) were significantly correlated with higher 3-year CIR. Adverse factors for NRM were grade III-IV acute GVHD (vs grade 0-II: 62% vs 22%, p<0.001), older patients (vs younger patients: 40% vs 24%, p=0.022), male (vs female: 37% vs 24%, p=0.041), a high leukocyte count (vs low leukocyte count: 45% vs 24%, p=0.010) and unrelated donors (vs related donors: 38% vs 18%, p=0.025). There was no association of the conditioning regimen with the outcome of transplantation. Multivariate analysis showed that a high leukocyte count (hazard ratio (HR), 2.52; 95% confidence interval (CI), 1.42–4.47; p=0.002) was an independent determinant of 3-year OS. Both CR2 status (HR, 3.82; 95% CI, 1.70–8.58; p=0.001) and unrelated donors (HR, 0.40; 95%CI, 0.17–0.90; p=0.027) were also correlated with 3-year CIR, while grade III-IV acute GVHD (HR, 3.97; 95% CI, 1.70–8.76; p<0.001) and a high leukocyte count (HR, 2.59; 95% CI, 1.22–5.52; p=0.014) were independently associated with higher 3-year NRM. Conclusions: This retrospective survey suggested that fludarabine-based RIST is a promising strategy for elderly patients with ALL in remission. Prognostic factors detected in this study might be useful to stratify patients for comparison of RIST with myeloablative hematopoietic stem cell transplantation. Disclosures:No relevant conflicts of interest to declare.

Does Iron Overload Really Matter in Stem Cell Transplantation?

Abstract 3029 Background:In patients with hematologic malignancies undergoing myeloablative hematopoietic stem cell transplantation (HSCT), an elevated serum ferritin prior to HSCT has been consistently associated with increased mortality. While serum ferritin is strongly correlated with liver iron content (LIC), to date no study has directly examined the effect of elevated LIC on HSCT outcomes. Furthermore, there are no studies of pre-transplantation chelation in this population. We conducted 2 prospective studies in patients with AML, ALL, or MDS undergoing HSCT. In the first, 45 patients were followed for >1 year with serial measurements of serum iron parameters and liver and cardiac iron (by MRI). In the second, we treated patients with severe iron overload (ferritin ≥ 1000 ng/ml and liver iron content (LIC) ≥ 5 mg/gdw) with deferoxamine 50 mg/kg/d starting in the weeks prior to transplantation and continuing until day -1, with the goal of controlling labile plasma iron (LPI) and especially the expected conditioning-induced rise in LPI. Results:The baseline characteristics of the patients on the observational study have been described in a prior publication (Armand et al., BBMT 2011). 5 patients (2 with AML in CR, 2 with AML and active disease, 1 with MDS) were enrolled on the chelation study; the median serum ferritin was 3, 746 ng/ml, and LIC 11.7 mg/gdw. They received deferoxamine for a median of 19 days before stem cell infusion. No significant drug-related toxicity occurred except for one episode of transient hypotension. There was no significant change in LIC after this short course of chelation. None of the 5 patients had a positive LPI assay before chelation or at the onset of conditioning; however, despite deferoxamine treatment, 2/5 had elevated LPI post-conditioning. Among those 5 patients, there was no disease relapse or death at a median follow-up of 20 months; only 1 patient developed grade II acute GVHD, and no patient developed VOD.Among the 50 patients in both studies combined, there was no significant change in serum ferritin, LIC or cardiac T2* in the first year after HSCT. After a median follow-up of 24 months, the estimated 2y overall survival (OS) and progression-free survival were 54% and 46%, respectively. When patients on the chelation study were excluded, there was a significant difference in OS for patients with pre-HSCT ferritin > 2, 500 ng/ml (2y OS 21% versus 62%, p =0.03) (Figure, panel A), similar to prior studies. However, there was no difference in OS, PFS, relapse or NRM for patients stratified by pre-HSCT LIC, regardless of the cutoff used and whether or not chelated patients were included (Figure, panel B). There was also no discernible impact of LIC on acute GVHD or VOD incidence. The difference in OS based on ferritin was apparent even among the patients with LIC<5 mg/gdw. Those results were confirmed in multivariable analyses. [Display omitted] Conclusion:We confirmed prospectively that pre-HSCT ferritin is an important prognostic marker in patients with AML, ALL or MDS undergoing HSCT. However, despite the strong correlation between ferritin and LIC, elevated LIC does not itself appear to be associated with survival. Thus, the prognostic value of ferritin may reflect other factors, such as inflammatory state, rather than iron burden. This calls into question the negative adverse impact attributed to iron overload in this population. Pre-transplantation chelation is challenging and does not reliably prevent the rise in LPI with conditioning. Despite this, our results in a very small number of patients raise the question of a possible beneficial effect of deferoxamine administered before HSCT that may be independent of parenchymal or labile iron chelation. Disclosures:Armand:Novartis Oncology: Research Funding. Neufeld:Novartis: Research Funding; Ferrokin BioSciences: Research Funding.

Outcome of Children Who Experience Disease Relapse Following Allogeneic Hematopoietic Stem Cell Transplantation for Hematologic Malignancies,

Abstract 4101 Introduction:According to the Center for International Blood and Marrow Transplantation and Research (CIBMTR) data, relapse accounts for 41% of deaths after matched sibling donor hematopoietic stem cell transplantation (HSCT) and 34% of deaths after unrelated donor HSCT. Overall long term survival of 25–30% has been reported in patients who relapse after HSCT. Most of these data are from adult studies. In a recent study, survival following a second allogeneic HSCT ranged from 25–50%. There are limited data on the treatment outcome of children who relapse after an allogeneic HSCT for hematological malignancies. Methods:This multicenter retrospective study was done with the primary objective to examine the incidence and outcome of children who experience relapse after allogeneic HSCT. Patients with a primary diagnosis of acute lymphatic leukemia (ALL), acute or chronic myeloid leukemia (AML or CML), juvenile myelomonocytic leukemia (JMML), biphenotypic leukemia (BL), acute undifferentiated leukemia (AUL), and myelodysplastic syndrome (MDS) were included. After IRB approval, data was collected from review of the medical charts of patients who underwent HSCT at 5 institutions across North America. Results:Data on 532 patients was analyzed; these included 328 males and 204 females. These included ALL (n=254), AML (n=187), MDS (n=35), CML (n=26), JMML (n=3), sAML (n=12), Biphenotypic leukemia (n=10), AUL (n=3) and 1 each with APL and secondary ALL. The median age at HSCT was 9.7 years (range 0.44 to 24.98). Four hundred and fifty (85%) of the 532 patients were in complete remission (CR) at the time of HSCT. Five hundred and fifteen (97%) underwent a myeloablative (MA) HSCT and 16 (3%) had a non-myeloablative (NMA) HSCT. Total body irradiation (TBI) was part of the conditioning therapy in 334 (63%) while 198 (37%) had chemotherapy based regimens. Standard graft versus host disease (GvHD) prophylaxis with calcineurin inhibitors and methotrexate was used in 76% of patients. Grade 1–2 acute GvHD developed in 180 (34%) of patients and 82 (15%) had grade 3–4 acute GvHD. Chronic GvHD was seen in 118 (22%) cases with half having extensive chronic GvHD. After HSCT, 85 (16%) patients died of transplant related complications at 1 year, with infection as the leading (26%) cause of death. The 2, 5 and 10 year overall survival for the entire group was 58.5%, 46% and 44% respectively. Following HSCT, 131 (25%) patients relapsed at a median duration of 7.7 months (range 0.6 to 66.4 months).Of the 131 patients who relapsed 80 (61%) received salvage therapy, 39(30%) did not get any therapy and data were not available for another 12 (9%) patients. Salvage therapy included a combination of withdrawal of immunosuppression, ALL or AML re-induction therapy, or other remission inducing agents, clofarabine, and/or donor lymphocyte infusions (n=22). After salvage therapy 46 (57.5%) patients achieved CR, 26 (32.5%) had no response, 3 (4%) partial response, 2 unknown and 4 (5%) had marrow aplasia and no recovery of counts.Sixty-three (48%) of the relapsed patients underwent a second HSCT: 26 (41%) received a MA, 21 (33%) NMA, 3 (5%) with no conditioning and in 13 (21%) conditioning therapy was unknown. Nearly 22 different conditioning regimens were used for the second HSCT. After the second HSCT 19 (41%) patients died because of transplant related mortality (TRM) and 24 patients died because of relapse. Seventeen (27%) patients are alive and disease free. Conclusions:Relapse remains a major complication following allogeneic HSCT for hematologic malignancies. Our data shows that patients who relapse after HSCT have poor prognosis. In our study 30 different salvage therapies were used for these patients. Currently there is no standard acceptable salvage therapy and most cooperative group or industry sponsored clinical trials exclude patients who underwent HSCT. In addition there are no standard conditioning regimens designed specifically for the second HSCT, which could contribute to the high TRM seen during second HSCT. There is urgent need to develop prospective clinical trials to better understand the optimal therapy for this group of patients. Disclosures:No relevant conflicts of interest to declare.

Eosinophilia As a Biomarker Predicting the Occurrence of Chronic Graft Versus Host Disease,

Abstract 4084 Introduction:Chronic graft-versus-host disease (cGVHD) is a major complication after allogeneic hematopoietic stem cell transplantation (HSCT) known to impair quality of life and functional status and adversely affects long-term survival. Given its impact on outcomes post HSCT, biological markers predicting cGVHD appearance could be useful. Eosinophilia has been reported to occur in the setting of both acute and cGVHD. Even though many physicians refer to eosinophilia as a predictor of GVHD, it is unclear whether eosinophilia can serve as a biomarker predicting occurrence of cGVHD in the general HSCT population. Objectives:In order to evaluate whether eosinophilia can predict the development of cGVHD, we have chosen to study a cohort of HSCT patients who developed eosinophilia while being tapered off their immunosuppressive drugs. Methods:From 01/2000 to 12/2009, a matched series of 112 patients who underwent allogeneic HSCT at City of Hope was identified. Of those, 56 patients presented with eosinophilia (>0.5×10^9 /L on two consecutive visits within 4 weeks, not related to relapse or documented allergy, drug reaction or parasitic infection) after day 120, while being tapered from their immunosuppressive drugs (case group). A control group (with no eosinophilia present on two consecutive visits within 4 weeks after day 120) was matched for the following criteria: age (±10 years), transplant year (± 2 years), HSC source (peripheral blood versus bone marrow), donor type (related vs. unrelated), female donor to male recipient, occurrence of acute GVHD and type of GVHD prophylaxis(tacrolimus/sirolimus vs. other). Results:A total of 112 patients were included in the analysis (Table no. 1). The most prevalent indication for HSCT was acute leukemia. Fifty seven percent of patients underwent myeloablative HSCT. There was no statistically significant difference between the case and control group for the matching criteria: age (p=0.88), HSC source, donor type, female donor to male recipient, occurrence of acute GVHD and type of GVHD prophylaxis (p=1). There was also no statistically significant difference between the groups for the different disease risk category (i.e. low risk, intermediate risk, high risk and non malignant) (p=0.4581). In the group of patients presenting with eosinophilia, 89% (50 out of 56) developed cGVHD, as opposed to 59% (33 out of 56) in the control group (p=0.0002, Chi square test). In this setting, eosinophilia was found to have a positive predictive value of 89%. In a multivariate logistic regression model, looking at the mentioned above known cGVHD risk factors, patients with eosinophilia were nearly 7 times more likely to develop cGVHD compared to those without eosinophila (p=0.0003, 95% CI 2.41–20.13).Table 1:Cases vs. Control characteristics: *Chi-Square test, T-testCaseControlP Value*No.(%)56 (100%)56 (100%)Age (yrs)P=0.88Median4644Range15–6717–68GenderP=0.85Male3132Female2524Disease risk statuesP=0.458Low risk23 (41%)25 (45%)Intermediate risk6 (11%)11 (20%)High risk23 (41%)17 (30%)Non malignant4 (7%)3 (5%)GVHD prophylaxisP=1Tacro/Siro29 (52%)29 (52%)Non Tacro/Siro27 (48%)27 (48%)Acute GVHDP=1No29 (52%)29 (52%)Yes27 (48%)27 (48%)Female donor to male recipientP=1No43 (77%)43 (77%)Yes13 (23%)13 (23%)Donor typeP=1Sibling33 (59%)33 (59%)MUD23 (41%)23 (41%)The median time from the development of eosinophilia to first GVHD sign was 20 days. Eighty four percent of patients both in the eosinophilia and the control groups presented with extensive GVHD grading, with skin, mouth and liver being the most prevalent sites for cGVHD occurrence. With a median follow up of 51 month for the entire cohort (range 5.5–132m) 80% of patients were alive in the eosinophilia group vs. 87% in the control group. Conclusions:The development of eosinophilia in the setting of tapering or discontinuation of immunosuppression may serve as a good predictor of cGVHD. Eosinophilia in this setting may be an indicator for early intervention. Disclosures:No relevant conflicts of interest to declare.

Keratinocyte Growth Factor and Stem Cell Factor to Improve Thymopoiesis after Autologous CD34 + Cell Transplantation in Rhesus Macaques

Deficient thymopoiesis and retarded recovery of naive CD4(+) T cells are important determinants of insufficient immune-competence following hematopoietic stem cell transplantation (HSCT). Although keratinocyte growth factor (KGF) may protect the thymic epithelium, stem cell factor (SCF) is involved in early thymopoiesis. We evaluated whether KGF alone or combined with SCF would affect thymopoiesis and hematologic recovery following myeloablative autologous HSCT into rhesus macaques. Purpose-bred adult rhesus macaques received 10(6) autologous CD34(+)-selected mononuclear bone marrow cells (BMC)/kg after 9 Gy myeloablative conditioning. Animals were treated with phosphate-buffered saline (PBS) (n = 2), KGF alone (n = 2), or KGF combined with SCF (n = 2). KGF-treated animals showed accelerated hematologic recovery, improved thymopoiesis, and enhanced naive T-cell recovery following transplantation. Improved T cell recovery was not associated with protection against cytomegalovirus reactivation nor with improved antibody response to tetanus toxoid vaccination. Animals treated with KGF and SCF experienced severe adverse events that precluded evaluation of thymopoiesis and T cell recovery. Collectively, our data confirm that KGF may enhance thymopoiesis.

Sequential chemotherapy and myeloablative allogeneic hematopoietic stem cell transplantation for refractory acute lymphoblastic leukemia

The prognosis of patients receiving allogeneic hematopoietic stem cell transplantation (HSCT) for refractory acute lymphoblastic leukemia (ALL) is very poor. To improve survival rates, we attempted to intensify the conditioning regimen with daunorubicin, vincristine, prednisolone, medium-dose etoposide, cyclophosphamide, and total body irradiation (DNR/VCR/PSL plus medium-dose VP/CY/TBI). Four patients in relapse or induction failure of B-precursor ALL without other complications underwent allogeneic HSCT. Initially, chemotherapy comprising DNR 60 mg/m(2) for 3 days, VCR 1.4 mg/m(2) for 1 day, and PSL 60 mg/m(2) for 3 days was administered, which was followed by medium-dose VP/CY/TBI; some modifications were made for individual patients. All patients achieved engraftment and complete remission after HSCT. Regimen-related toxicities were tolerable and no patient died within 100 days. Two patients were alive without disease on days 563 and 1,055. The third patient relapsed on day 951, while the fourth died on day 179 without disease. Our results indicate that intensified myeloablative HSCT should be considered for patients with refractory ALL.

Peripheral Blood Lymphocyte and Monocyte Recovery and Survival in Acute Leukemia Postmyeloablative Allogeneic Hematopoietic Stem Cell Transplant

Many previous studies of immune reconstitution (IR) postallogeneic hematopoietic stem cell transplantation (HSCT) have focused on lymphocyte recovery. Recognizing that IR involves complex interactions between innate and adaptive immune networks, we hypothesized that patterns of both monocyte and lymphocyte recovery could provide additional prognostic information. To test our hypothesis, we analyzed data from 135 consecutive patients undergoing myeloablative allogeneic HSCT for acute myeloid (AML) and lymphoblastic leukemia (ALL) from 2001 to 2010. The absolute lymphocyte and monocyte counts (ALC and AMC, respectively) were determined longitudinally at days +15, +30, +60, and +100, and correlated with clinical outcomes. At the day +30 time point, both ALC and AMC >0.3 × 10(9) cells/L were strongly associated with improved survival (overall survival [OS] 29.6 months versus 5.4 months, P = .006 and 25.3 months versus 5.1 months, P = .01 respectively), a pattern that generally continued through the day +100 evaluation. Multivariate analysis revealed the following independent prognostic factors: early disease status at transplantation, the development of chronic GVHD, the day +30 AMC, day +100 AMC, and day +100 ALC. To further explore whether any inherent patterns in the timing of lymphocyte and monocyte recovery had prognostic value post-HSCT, we performed unsupervised hierarchical clustering on the longitudinal hematopoietic parameters studied in this cohort. Four clusters of patients were identified: clusters A-D. Patient clusters B and D both demonstrated improved ALC and AMC recovery at the day +60 and day +100 time points and had significantly improved OS compared with clusters A and C (57.8 months versus 19.7 and 4.4 months, respectively, P < .001). Our data suggest that patients with poor lymphocyte and monocyte recovery beyond the day +60 time points may be at risk for poorer outcomes, and that further investigation into lymphoid/myeloid interactions in developing individualized immunotherapy is warranted.

Second cancers after hematopoietic stem cell transplantation with total body irradiation conditioning regimen in hematologic disorders.

6548 Background: Myeloablative hematopoietic stem cell transplantation (HSCT) is the treatment of choice for several malignant hematologic disorders. Long-term survivors are increasing by the improvement of treatment protocol and supportive care. The purpose of this retrospective study was to define the incidence of second cancers in a cohort of very long term survivors treated with total body irradiation (TBI) as a part of conditioning prior to HSCT. Methods: Between 1992 and 2005, 1446 patients with hematologic disorders underwent HSCT with TBI conditioning regimen. Total 780 patients with disease free at least 5 years after HSCT were evaluated. The dose of TBI was median 12 Gy. TBI was fractionated from 1.65 to 2 Gy per fraction, twice a day. The graft-versus-host disease (GVHD) prophylaxis was cyclosporine associated to methotrexate in the majority of patients. The cumulative probability of a new malignancy was estimated by Kaplan-Meier method. The log-rank test was used for statistical comparison of potential risk factors for second malignancy. Multivariate analysis was performed using Cox proportional hazard model. Results: Median age at transplantation was 30 years (range, 2 - 66). Median duration of follow up was 9.3 years (range, 5.0 – 18.0). Second cancer occurred in 17 patients. The median time from transplantation to the diagnosis of second cancer was 5.6 years. Three tongue cancers, 1 tonsil cancer, 3 thyroid cancers, 2 breast cancers, 1 colon cancer, 1 brain tumor and 2 bone tumors were detected. The posttransplant lymphoproliferative disorders were observed in 4 patients. The experience of chronic extensive GVHD was the statistically significant factor associated with an increased risk of second cancer in univariate and multivariate analysis (p < 0.0001 and p < 0.0001, respectively). Conclusions: Long term surveillance of patients undergoing HSCT is essential to detect late-developing cancers, particularly for patients who received immunosuppressive therapy for a long period by chronic extensive GVHD. Guidelines should be developed in regard to screening and prevention of second cancers for the benefit of patients.

Effect of combined lymphocyte and monocyte recovery on survival post myeloablative allogeneic hematopoietic stem cell transplant for acute leukemia.

6561 Background: Many previous studies of immune reconstitution (IR) post-allogeneic hematopoietic stem cell transplantation (HSCT) have focused on lymphocyte recovery. Recognizing that IR involves complex interactions between innate and adaptive immune systems, we hypothesized that monocyte recovery along with lymphocyte recovery could provide additional prognostic information. Methods: To test our hypothesis, we analyzed data from 135 consecutive patients undergoing myeloablative allogeneic HSCT for AML and ALL. The absolute lymphocyte counts and monocyte counts (ALC and AMC, respectively) were determined longitudinally at days +15, +30, +60, +100 and correlated with outcomes. Results: At the day +30 time point, both ALC and AMC > 0.3 x 109 cells/L were strongly associated with improved survival (OS 29.6 months vs. 5.4 months, p=0.006 and 25.3 months vs. 5.1 months, p=0.01 respectively), a pattern that continued through the day +100 evaluation. Multivariate analysis including age at transplant, CD34+ cell dose, related vs. unrelated HSCT, and grade of acute GVHD revealed the following independent prognostic factors: age at transplant (RR 4.31, 95% CI 1.45 – 13.7, p=0.008), day +100 ALC > 0.3 x 109 cells/L (RR 0.34, 95% 0.16 – 0.82, p=0.02) and day +100 AMC > 0.3 x 109 cells/L (RR 0.33, 95% CI 0.18 – 0.67, p=0.002). To further explore whether any patterns in the timing of lymphocyte and monocyte recovery had prognostic value post-HSCT, we performed unsupervised hierarchical clustering on the longitudinal hematopoietic parameters studied in this cohort. Four clusters of patients were identified, clusters A-D. Patient clusters B and D demonstrated improved ALC and AMC recovery at the day +60 and day +100 time points and had significantly improved OS compared with clusters A and C (57.8 months vs. 19.7 and 4.4 months, respectively, p<0.001). Conclusions: IR is paramount to the success of transplant as a therapeutic modality for high-risk hematologic malignancies. Our data suggests that monocyte/macrophage reconstitution may be as important as, and supportive to, lymphocyte recovery post allogeneic HSCT.