Associations of High-Dose Melphalan Pharmacokinetics and Outcomes in the Setting of a Randomized Cryotherapy Trial.

High-dose melphalan followed by autologous stem cell transplantation remains the standard of care for eligible patients with multiple myeloma, but disease response and toxicity, including severe mucositis, varies among patients. Our randomized trial investigated duration of cryotherapy (2 and 6 h) for reduction of mucositis prevalence and severity and explored factors associated with variability in pharmacokinetics and outcomes from melphalan therapy. The results demonstrate that 2-h is at least as effective as 6-h cryotherapy in decreasing severe mucositis. From a population pharmacokinetic model, we identified that fat-free mass, hematocrit, and creatinine clearance were significant covariates, as reported previously. Furthermore, we observed the rs4240803 SLC7A5 polymorphism was significantly associated with pharmacokinetic variability, and pharmacokinetics was associated with both mucositis and neutropenia. However, melphalan exposure was not associated with progression-free or overall survival in our dataset. These findings contribute to ongoing efforts to personalize melphalan dosing in transplant patients.

A single center's experience using four different front line mobilization strategies in lymphoma patients planned to undergo autologous hematopoietic cell transplantation.

In an otherwise eligible patient with relapsed lymphoma, inadequate mobilization of hematopoietic stem cells (HSCs) is a limiting factor to proceeding with an autologous hematopoietic cell transplantation (auto-HCT). Multiple strategies have been used to mobilize an adequate number of HSCs with no obvious front-line strategy. We report a single institutional experience mobilizing HSCs using four different approaches in lymphoma patients. We prospectively collected mobilization outcomes on patients planned to undergo auto-HCT at Ohio State University. We report results of first mobilization attempts for all relapsed or refractory lymphoma patients between 2008 and 2014. We identified 255 lymphoma patients who underwent mobilization for planned auto-HCT. The 255 lymphoma patients underwent the following front line mobilization strategies: 95 (37%) G-CSF alone, 38 (15%) chemomobilization (G-CSF+chemotherapy), 97 (38%) preemptive day 4 plerixafor, and 25 (10%) rescue day 5 plerixafor. As expected, there were significant differences between cohorts including age, comorbidity indices, histology, and amount of prior chemotherapy. After controlling for differences between groups, the odds of collecting 2 × 106/kg HSCs on the first day of collection and 5 × 106/kg HSCs in total was the highest in the cohort undergoing chemomobilization. In conclusion, our experience highlights the effectiveness of chemomobilization.

Endothelial chimerism in chronic sclerotic-type chronic graft-versus-host disease (GVHD) and GVHD-associated angiomatosis.

Graft-versus-host disease-associated angiomatosis (GVHD-AA) is an uncommon manifestation of chronic GVHD consisting of friable vascular proliferations. Using fluorescence in situ hybridization, we demonstrate the presence of donor-derived endothelial cells within areas of GVHD-AA. This is the first documented occurrence of a benign neoplastic growth in relationship to a form of chronic GVHD.

Plasmacytoid dendritic cells in allogeneic hematopoietic cell transplantation: benefit or burden?

Plasmacytoid dendritic cells (pDCs) bridge innate and adaptive immune responses and have important roles in hematopoietic engraftment, GvHD and graft-versus-leukemia responses following allogeneic hematopoietic cell transplantation (HCT). In addition, pDCs mediate antiviral immunity, particularly as they are the body's primary cellular source of type I interferon. Given their pleiotropic roles, pDCs have emerged as cells that critically impact transplant outcomes, including overall survival. In this article, we will review the pre-clinical and clinical literature, supporting the crucial roles that pDCs assume as key immune effector cells during HCT.

Allogeneic hematopoietic cell transplant for AML: no impact of pre-transplant extramedullary disease on outcome.

The impact of extramedullary disease (EMD) in AML on the outcomes of allogeneic hematopoietic cell transplantation (alloHCT) is unknown. Using data from the Center for International Blood and Marrow Transplant Research, we compared the outcomes of patients who had EMD of AML at any time before transplant, with a cohort of AML patients without EMD. We reviewed data from 9797 AML patients including 814 with EMD from 310 reporting centers and 44 different countries, who underwent alloHCT between and 1995 and 2010. The primary outcome was overall survival (OS) after alloHCT. Secondary outcomes included leukemia-free survival (LFS), relapse rate and treatment-related mortality (TRM). In a multivariate analysis, the presence of EMD did not affect either OS (hazard ratio 1.00, 95% confidence interval (CI) 0.91-1.09), LFS (0.98, 0.89-1.09), TRM (relative risk 0.92, 95% CI 0.80-1.16, P=0.23) or relapse (relative risk=1.03, 95% CI, 0.92-1.16; P=0.62). Furthermore, the outcome of patients with EMD was not influenced by the location, timing of EMD, or intensity of conditioning regimen. The presence of EMD in AML does not affect transplant outcomes and should not be viewed as an independent adverse prognostic feature.

Health-related quality of life in patients who develop bronchiolitis obliterans syndrome following allo-SCT.

Bronchiolitis obliterans syndrome (BOS) remains an important complication following allo-SCT. The development of this condition portends a higher morbidity and mortality but the effect on heath-related quality of life (HRQL) is unknown. The aim of this study was to determine whether the development of BOS impacted HRQL compared with patients without BOS. This Institutional Review Board-approved prospective study analyzed 126 patients who underwent allo-SCT at our institution. Patients were administered three HRQL survey tools (SF-36, European Organization for Research and Treatment of Cancer QLQ-c30 and St George Respiratory Questionnaire (SGRQ)) before transplant and then again at 6 months, 1 year and 2 years after transplant. Patients were analyzed in three groups determined by highest chronic GVHD (cGVHD) severity and BOS status. Overall, our study group had improving HRQL after transplant when measured over time, measured by the SF-36 with stable HRQL, when measured by the SGRQ total score and QLQ-c30. Patients that developed BOS had significantly worse HRQL scores measured by the SGRQ and the SF-36 physical composite score. This difference was not explained by the severity of cGVHD that patients with BOS developed.

The hematopoietic stem cell transplant comorbidity index can predict for 30-day readmission following autologous stem cell transplant for lymphoma and multiple myeloma.

Patients who undergo autologous stem cell transplant (ASCT) for hematologic malignancies frequently have multiple comorbidities. The hematopoietic cell transplantation comorbidity index (HCT-CI), a transplant-specific modification of the Charlson comorbidity index, can predict risk of readmission following allogeneic stem cell transplant. Its utility in the autologous setting is unknown. We evaluated 620 patients who underwent ASCT at the Ohio State University from 2007 to 2012 for lymphoma or multiple myeloma (MM) to identify factors associated with readmission. Univariable and multivariable logistic regression were used to estimate the odds of readmission within 30 days of discharge following ASCT. A Cox proportional hazards model was used to evaluate OS. Sixty-four patients were readmitted within 30 days; the most common indications were fever and prolonged gastrointestinal toxicity. MM compared with lymphoma (odds ratio (OR) 1.89, 95% confidence interval (95% CI): 1.06-3.38, P=0.03), HCT-CI⩾3 (OR 1.74, 95% CI: 1.03-2.96, P=0.04) and length of hospitalization ⩾28 days (OR 3.14, 95% CI: 1.26-7.83, P=0.01) remained significantly associated with 30-day readmission in a multivariable model. While the model had excellent fit (P>0.75), its ability to predict individual patients who would be readmitted was less than acceptable (receiver-operator curve=0.64, 95% CI: 0.57-0.71). In a multivariable proportional hazards model, 30-day readmission (hazards ratio (HR) 1.81, 95% CI: 1.04-3.18, P=0.04), length of hospitalization ⩾28 days (HR 4.93, 95% CI: 2.65-9.18, P<0.001) and chemorefractory disease (HR 3.08, 95% CI: 1.74-5.43, P<0.001) were independently associated with inferior OS, but HCT-CI was not. Evaluation of other assessment tools may allow better prediction of outcomes following ASCT.

An effective mobilization strategy for lymphoma patients after failed upfront mobilization with plerixafor.

In an otherwise eligible patient, inadequate mobilization of PBSCs is a limiting factor to proceeding with an auto-ASCT. In such situations, plerixafor is commonly added to improve PBSC collection yields along with cytokine (G-CSF alone) or chemomobilization (chemotherapy+G-CSF). Individually, both strategies are proven to be safe and effective. Here we report six patients who underwent successful mobilization with combination chemomobilization plus plerixafor after upfront failure of cytokine mobilization plus plerixafor. The median CD34(+) cell yield after chemomobilization was 2.48 × 10(6)/kg (range 0.99-8.49) after receiving one to two doses of plerixafor. All patients subsequently underwent ASCT without major unforeseen toxicities and engrafted successfully. No significant delays in time to neutrophil recovery were observed. Our experience highlights the safety and effectiveness of chemomobilization with plerixafor after G-CSF plus plerixafor (G+P) failure and suggests this is a viable salvage strategy after initial failed G+P mobilization.

CS1-specific chimeric antigen receptor (CAR)-engineered natural killer cells enhance in vitro and in vivo antitumor activity against human multiple myeloma.

Multiple myeloma (MM) is an incurable hematological malignancy. Chimeric antigen receptor (CAR)-expressing T cells have been demonstrated successfully in the clinic to treat B-lymphoid malignancies. However, the potential utility of antigen-specific CAR-engineered natural-killer (NK) cells to treat MM has not been explored. In this study, we determined whether CS1, a surface protein that is highly expressed on MM cells, can be targeted by CAR NK cells to treat MM. We successfully generated a viral construct of a CS1-specific CAR and expressed it in human NK cells. In vitro, CS1-CAR NK cells displayed enhanced MM cytolysis and interferon-γ (IFN-γ) production, and showed a specific CS1-dependent recognition of MM cells. Ex vivo, CS1-CAR NK cells also showed similarly enhanced activities when responding to primary MM tumor cells. More importantly, in an aggressive orthotopic MM xenograft mouse model, adoptive transfer of NK-92 cells expressing CS1-CAR efficiently suppressed the growth of human IM9 MM cells and also significantly prolonged mouse survival. Thus, CS1 represents a viable target for CAR-expressing immune cells, and autologous or allogeneic transplantation of CS1-specific CAR NK cells may be a promising strategy to treat MM.

Association of pre-transplantation positron emission tomography/computed tomography and outcome in mantle cell lymphoma.

Positron emission tomography/computed tomography (PET/CT)-positive findings before autologous SCT (auto-SCT) are associated with inferior PFS and OS in patients with relapsed Hodgkin's and diffuse large B-cell lymphoma. We classified pre-transplant PET/CT performed before auto-SCT as positive or negative to evaluate the impact of pre-transplant PET/CT in mantle cell lymphoma (MCL). In 29 patients, 17 were PET/CT(-) and 12 were PET/CT(+). PET/CT(+) patients were younger (P=0.04), had lower MCL International Prognostic Index (MIPI, P=0.04) scores, but increased bulky adenopathy >5 cm (45% vs 13%, P=0.09). With a median follow-up of 27 months (range: 5-55 months), 7 patients relapsed (4 in the PET/CT(-) group and 3 in the PET/CT(+) group) with 2 deaths in the PET/CT(+) group without a documented relapse. The estimated 2-year PFS was 64% (95% confidence interval (CI): 0.30-0.85) vs 87% (95% CI: 0.57-0.97) in PET/CT(+) and PET/CT(-) patients, respectively (P=0.054). OS was significantly decreased in PET/CT(+) patients (P=0.007), with 2-year estimates of 60% (95% CI: 0.23-0.84) vs 100% in PET/CT(-) patients. A positive pre-transplant PET/CT is associated with a poor prognosis in patients with MCL. Additional factors may impact the prognostic value of PET/CT, as several PET/CT(+) patients remain in remission.

How we approach patient evaluation for hematopoietic stem cell transplantation.

The evaluation of patients for hematopoietic stem cell transplantation is a complex process. The decision to recommend transplantation is not simply dependent on patient diagnosis; instead it is a specialized analytic decision process intricately dependent on a number of variables including patient age, performance status, medical comorbidities, family support structure, socioeconomic viability and motivation to participate in self-care, to name a few. The process of pre-transplant patient evaluation has substantial variability across different transplant centers, owing to lack of formal published guidelines. This review summarizes the process of pre-transplant patient evaluation and workup, and aims to describe components of a well-organized and evidenced-based patient selection process for SCT.

Pulmonary Nocardia and Aspergillus co-infection in a patient with chronic graft-versus-host disease.

Immunosuppression and chronic graft-versus-host disease (GVHD) are major risk factors for the development of invasive pulmonary aspergillosis in bone marrow transplant patients. Although nocardial infections are well described in hematopoietic stem cell transplantation (HSCT) recipients, little information is available about the incidence of nocardiosis in patients with chronic GVHD after HSCT. Coexistence of invasive pulmonary aspergillosis and nocardiosis following non-myeloablative HSCT has not been reported previously. With the increasing use of pentostatin in the treatment of chronic GVHD in future and other nucleoside analogues as preparative regimens in patients undergoing reduced-intensity conditioning transplantation, the possibility of co-infection with rare organisms should be kept in mind while assessing at-risk patients.

Mobilizing stem cells from normal donors: is it possible to improve upon G-CSF?

Currently, granulocyte colony stimulating factor (G-CSF) remains the standard mobilizing agent for peripheral blood stem cell (PBSC) donors, allowing the safe collection of adequate PBSCs from the vast majority of donors. However, G-CSF mobilization can be associated with some significant side effects and requires a multi-day dosing regimen. The other cytokine approved for stem cell mobilization, granulocyte-macrophage colony stimulating factor (GM-CSF), alters graft composition and may reduce the development of graft-versus-host disease, but a significant minority of donors fails to provide sufficient CD34+ cells with GM-CSF and some experience unacceptable toxicity. AMD3100 is a promising new mobilizing agent, which may have several advantages over G-CSF for donor mobilization. As it is a direct antagonist of the interaction between the chemokine stromal-derived factor-1 and its receptor CXCR4, AMD3100 mobilizes PBSCs within hours rather than days. It is also well tolerated, with no significant side effects reported in any of the clinical trials to date. Studies of autologous and allogeneic transplantation of AMD3100 mobilized grafts have demonstrated prompt and stable engraftment. Here, we review the current state of stem cell mobilization in normal donors and discuss novel strategies for donor stem cell mobilization.

Once daily ganciclovir as initial pre-emptive therapy delayed until threshold CMV load > or =10000 copies/ml: a safe and effective strategy for allogeneic stem cell transplant patients.

Quantitative polymerase chain reaction (QPCR) for cytomegalovirus (CMV) is emerging as the preferred screening method for detection of CMV viremia in patients following allogeneic bone marrow and peripheral blood stem cell transplant. However, there are currently no universally accepted QPCR treatment thresholds at which to start pre-emptive therapy. We report here results of a pre-emptive therapy strategy using ganciclovir (GCV) 5 mg/kg initiated once daily (ODG) delayed till a threshold CMV load of > or =10 000 copies/ml whole blood in clinically stable patients. Sixty-nine at risk patients underwent allogeneic stem cell transplant. 48/69 (70%) patients had an initial episode of CMV viremia. 5/48 (10%) cleared viremia without requiring treatment. 28/43 (65%) patients requiring treatment initiated treatment with ODG. 17/28 (61%) patients successfully cleared CMV viremia on ODG, 10/28 (36%) patients required dose escalation to twice daily GCV for increasing viral loads. There were two cases of CMV disease (colitis) and no deaths due to CMV disease in patients initiating treatment with ODG. We conclude delaying pre-emptive therapy with ODG until whole blood QPCR> or =10 000 copies/ml is a safe and effective strategy for CMV viremia after allogeneic stem cell transplant in clinically stable patients.

Reduced risk of acute GVHD following mobilization of HLA-identical sibling donors with GM-CSF alone.

We retrospectively reviewed the results of transplanting peripheral blood progenitor cell (PBPC) allografts from HLA-matched sibling donors mobilized using various hematopoietic cytokines. Patients had received allografts mobilized with Granulocyte colony-stimulating factor (G-CSF) (G, N = 65) alone, G plus Granulocyte-macrophage colony stimulating factor (GM-CSF) (G/GM, N = 70), or GM-CSF alone at 10 or 15 microg/kg/day (GM, N = 10 at 10 microg/kg/day and 21 at 15 microg/kg/day). The CD34+ and CD3+ cell content of grafts were significantly lower following GM alone compared to G alone (P < 0.001 and 0.04, respectively). Nonhematopoietic toxicity observed in donors precluded dose escalation of GM-CSF beyond 10 microg/kg/day. Hematopoietic recovery was similar among all three groups. Grades II-IV acute graft-versus-host disease (GVHD) was observed in only 13% of patients in the GM alone group compared to 49 and 69% in the G alone or G/GM groups, respectively (P < 0.001). In a multivariate analysis, receipt of PBPC mobilized with GM alone was associated with a lower risk of grades II-IV acute GVHD (hazard ratio 0.21; 95% CI 0.073, 0.58) compared to G alone or G/GM. There were no differences in relapse risk or overall survival among the groups. Donor PBPC grafts mobilized with GM-CSF alone result in prompt hematopoietic engraftment despite lower CD34+ cell doses and may reduce the risk of grades II-IV acute GVHD following HLA-matched PBPC transplantation.

Low-dose short-course intravenous ganciclovir as pre-emptive therapy for CMV viremia post allo-PBSC transplantation.

In contrast to allogeneic bone marrow transplantation (allo-BMT), there is a paucity of data on cytomegalovirus (CMV) infection and preemptive therapy (PT) strategies following allogeneic peripheral blood stem cell (allo-PBSC) transplantation. We report here on the patterns of CMV infection in a cohort of 225 patients following sibling donor allo-PBSC transplantation. In an attempt to reduce neutropenia, we used intravenous low-dose short-course (LDSC) ganciclovir (GCV) 5 mg/kg once daily for 21 days as preemptive therapy. A total of 165 recipient-donor pairs were CMV seropositive. An initial episode of viremia (detected by shell vial/tube culture) occurred in 75/165 (45%) at a median of day +35 (17-445) post allo-PBSC. In all, 58 patients received PT with LDSC GCV. Among 58, 55 (94%) completed the 21-day course of PT. A second episode of viremia occurred in 19/58 (33%) at day+80 (50-174) and a third episode in 5/58 (9%) at day+134 (103-218). Among patients receiving LDSC GCV, 5/58(9%) developed disease (four pneumonia, one colitis) at day+211 (63-487). No patient on LDSC GCV exhibited a decline in their ANC below 500/microl and none required growth factors. LDSC GCV is extremely well tolerated and cost-effective as PT for CMV viremia following allo-PBSC transplantation.

Clinical application of hematopoietic progenitor cell expansion: current status and future prospects.

In the past decade, we have witnessed significant advances in ex vivo hematopoietic stem cell culture expansion, progressing to the point where clinical trials are being designed and conducted. Preclinical milestone investigations provided data to enable expansion of portions of hematopoietic grafts in a clinical setting, indicating safety and feasibility of this approach. Data derived from current clinical trials indicate successful reconstitution of hematopoiesis after myeloablative chemoradiotherapy using infusion of ex vivo-expanded perfusion cultures. Future avenues of exploration will focus upon refining preclinical and clinical studies in which cocktails of available cytokines, novel molecules and sophisticated expansion systems will explore expansion of blood, marrow and umbilical cord blood cells.

Fludarabine and melphalan-based conditioning for patients with advanced hematological malignancies relapsing after a previous hematopoietic stem cell transplant.

Severe regimen-related toxicity often complicates second transplant procedures performed in patients with hematological malignancies that have relapsed after an initial hematopoietic stem cell (HSC) transplant. Therefore, we studied the safety and efficacy of a reduced-intensity fludarabine and melphalan based conditioning regimen in 11 patients who had relapsed following an autologous (n = 7) or allogeneic (n = 4) HSC transplant. All patients received allogeneic peripheral blood HSC from either an HLA-identical (n = 7) or an HLA-mismatched (n = 4) relative. Diagnoses included AML (n = 9), ALL (n = 1), or Hodgkin's disease (n = 1). Only one patient was in complete remission at the time of second transplant. The median interval between first transplant and relapse was 163 days (range 58-1885). Recipients of HLA-mismatched transplants received antithymocyte globulin in addition to fludarabine and melphalan as part of the conditioning regimen. All 11 patients received acute GVHD prophylaxis consisting of tacrolimus and methotrexate. Ten of 11 patients achieved hematopoietic engraftment with a median time to absolute neutrophil count >0.5 x 10(9)/l and to platelet count of >20 x 10(9)/l of 14 and 19 days, respectively. All engrafting patients achieved 100% donor chimerism on initial analysis, except for one with persistent leukemia at day +19. Two patients experienced grade 3 regimen-related toxicity, manifesting as acute renal failure. Acute GVHD grades 2-4 occurred in two recipients and chronic GVHD in four. The 100-day mortality from all causes was 36%. Ten of 11 patients (91%) died a median of 140 days (range 9-996) after the second transplant. The causes of death included relapse (n = 5), sepsis (n = 4), and idiopathic pneumonia syndrome (n = 1). One patient with AML survives in remission at 880 days post-transplant. We conclude that fludarabine- and melphalan-based conditioning promotes full donor chimerism, even following HLA-mismatched transplants. However, the regimen may be more beneficial when applied to patients undergoing allogeneic HSC transplantation earlier in their disease course.