Hematopoietic cell transplantation in older patients with hematologic malignancies: replacing high-dose cytotoxic therapy with graft-versus-tumor effects

The risk of cytomegalovirus infection in non-myeloablative peripheral stem cell transplantation compared with conventional bone marrow transplantation

Non-myeloablative allogeneic peripheral stem cell transplantation (NST) is a novel therapeutic strategy for patients with hematologic malignancies. Whether non-myeloablative transplants are associated with increased risk of cytomegalovirus (CMV) infections is unknown. To clarify this issue, we compared the outcome of CMV infection following 24 allogeneic non-myeloablative peripheral blood stem cell transplants and 40 conventional bone marrow transplants (CBT). The NST regimen consisted (mg/kg). Twelve patients (50%) in the NST group and 17 (43%) in the CBT group developed positive antigenemia before day 100 (p=0.60). The time to the first appearance of positive antigenemia was not different between these two groups (p=0.40), and two groups showed similar initial and maximal antigenemia values (p=0.56 and p=0.68, respectively). Only one case of CMV colitis developed in the CBT group whereas CMV disease did not develop in the NST group. Although statistically insignificant, the treatment response against CMV antigenemia using ganciclovir was in favor of NST group. In conclusion, there was no difference in the risk of CMV infection between NST group and CBT group. Further prospective and controlled study is needed to clarify the impact of non-myeloablative procedure on the outcome of CMV infection.

Decreased RBCTs after reduced intensity conditioning allogeneic stem cell transplantation: predictive value of prior Hb level

BACKGROUND

RBCT (RBCT) requirements of stem cell transplant (SCT) recipients are often substantial and may be related to transplant type.

STUDY DESIGN AND METHODS

An analysis was done of RBCT requirements and Hb recovery kinetic in the first 60 days after HLA-identical sibling allogeneic SCT in a series of 110 consecutive patients treated for various malignant diagnoses. Patients were prepared with either an antithymocyte globulin (ATG) and reduced intensity chemotherapy-based conditioning (RIC) (n=64) or a myeloablative conditioning regimens (MAC; n=46). Patients received marrow (n=64) or PBPCs (n=46).

RESULTS

Overall, intensity of conditioning regimen (RIC vs. MAC; p=0.0005) and graft source (PBPC vs. marrow; p<0.0001) independently predicted RBCT requirements. Hb recovery was accelerated after RIC when compared to MAC allo-SCT (p=0.02). In RIC patients, RBCTs were inversely correlated to Hb level before conditioning (p<0.0001) and the dose of ATG (p=0.009). Moreover, Hb level before allo-SCT significantly influenced Hb recovery kinetic after RIC but had no impact on RBCT requirements and Hb recovery after MAC.

CONCLUSION

Thus, RIC conditioning creates a different pattern of erythropoiesis recovery as compared to a MAC regimen and suggest a need for studies aimed at further reducing RBCT and accelerating Hb recovery.

Haematopoietic stem cell transplantation with non-myeloablative conditioning in the outpatient setting: results, complications and admission requirements in a single institution

Thirty patients with haematological malignancies received peripheral blood stem cells from human leucocyte antigen (HLA)-identical sibling donors after non-myeloablative conditioning with fludarabine and total body irradiation. Twenty-seven patients received the transplant as an outpatient procedure. All patients engrafted. The probability of acute graft-versus-host disease (GVHD) grades II-IV and extensive chronic GVHD was 57% and 80%, respectively. Patients alive on day +365 experienced a median of 44 d (range 4-151) of hospitalization during the first year. In the entire cohort, GVHD accounted for 22%, infections for 18%, thrombotic thrombocytopenic purpura (TTP) for 16% and engraftment syndrome for 14% of the time in hospital. The 1-year risk of TTP was 26%. Acute GVHD was a risk factor for the development of TTP (P = 0.008). With a median follow-up of 602 d, the 2-year estimates for overall survival, progression-free survival, non-relapse mortality and relapse related mortality were 68%, 43%, 22% and 13%, respectively. This transplantation regimen is feasible and induces long-term remissions in heavily pretreated patients. The procedure can be performed in the outpatient setting, but complications could result in a substantial number of admissions during the first year.

Allogeneic stem cell transplantation as immunotherapy for nonhematological cancers

Over the past two decades biologic therapy has played an increasing role in the treatment of cancer. While this field is still early in its development, there now exists compelling evidence that the immune system is capable of detecting and eliminating cancer cells. Although the majority of immunotherapy approaches for metastatic cancer involve strategies designed to enhance autologous immunity, most would agree that the graft-versus-leukemia reaction induced following allogeneic stem cell transplantation represents modern day's most potent form of cancer immunotherapy. While allogeneic stem cell transplantation has gained recognition as a potentially curative "immunotherapy" for a growing number of different hematological malignancies, its efficacy in inducing antimalignancy effects against nonhematological cancers has only recently begun to be investigated. The historical basis, development, and preliminary clinical results of allogeneic stem cell transplantation as a form of immunotherapy for treatment refractory solid tumors are reviewed.

Targeted cancer therapy and immunosuppression using radiolabeled monoclonal antibodies

Radioimmunotherapy (RIT) as a means to target radiation therapy to tumor cells or to specifically suppress host immunity specifically in the setting of allogeneic transplantation is a promising new strategy in the armory of today's oncologist. Different approaches of RIT such as injection of a stable radioimmunoconjugate or the use of pretargeting are available. The choice of the radionuclide used for RIT depends on its radiation characteristics with respect to the malignancy or cells targeted. beta-Emitters with their lower energy and longer path length are more suitable for targeting bulky, solid tumors, whereas alpha-emitters with their high linear energy transfer and short path length are better suited to target cells or tumors of the hematologic system. Encouraging results have been obtained using these approaches treating patients with hematologic malignancies. While the results in solid tumors are somewhat less favorable, new strategies for patients with minimal residual disease (MRD), using adjuvant and locoregional treatment, are currently being investigated. In this report, we outline basic principles of RIT, give an overview of available radioimmunoconjugates and their clinical applications with special emphasis on their use in hematologic malignancies, including use in conditioning regimens for stem cell transplantation (SCT).

Allogeneic Hematopoietic Stem Cell Transplantation for Lymphoma

For patients with relapsed or refractory Hodgkin's or non-Hodgkin's lymphomas, allogeneic hematopoietic stem cell transplantation (HSCT) is a treatment option when autologous HSCT fails to achieve durable remission or is deemed inappropriate. Allogeneic HSCT can result in long-term survival even in patients with refractory lymphomas. The efficacy of allogeneic HSCT is attributed, at least in part, to an immune-mediated graft-versus-lymphoma (GVL) effect that can also be associated with significant toxicity resulting from graft-versus-host disease. However, clinical evidence of a potent GVL effect is inconsistent. Reduced-intensity conditioning before allogeneic HSCT can facilitate the use of this treatment in older patients and those at high risk. The decrease in toxicity with reduced-intensity regimens may be associated with a loss of antitumor effects. Patients with lymphoma should be selected for allogeneic HSCT on the basis of characteristics that strongly influence transplant outcomes, including histology, chemosensitivity, and donor source.

Current approach to diagnosis and management of chronic lymphocytic leukemia

The care of patients with chronic lymphocytic leukemia (CLL) has changed dramatically during the past decade. This review summarizes the work-up of lymphocytosis and the current diagnostic criteria and management of CLL. Although clinical staging (Rai and Binet) remains the foundation for determining prognosis, 50% of patients with early-stage disease at diagnosis will experience an aggressive course of disease with early progression and premature death due to CLL. New laboratory techniques (CD38, fluorescence in situ hybridization [FISH]) can identify some patients with early-stage CLL at high risk of rapid disease progression. The array of treatment options has expanded in recent years and now includes monoclonal antibodies used alone or in combination with purine nucleoside analogues and alkylating agents, which have culminated in dramatically improved response rates. Supportive care guidelines now include vaccination strategies, surveillance for secondary malignancies, and aggressive management of infectious complications. An early hematology consultation is recommended for all patients at diagnosis to identify and counsel high-risk patients with early-stage disease who may benefit from more frequent follow-up or early treatment as part of a clinical trial.

Clinical "cytokine storm" as revealed by monocyte intracellular flow cytometry: correlation of tumor necrosis factor alpha with severe gut graft-versus-host disease

BACKGROUND & AIMS

Gut graft-versus-host disease (GVHD) contributes significantly to lethality after allogeneic hematopoietic stem-cell transplantation (HSCT). In murine models, macrophage secretion of interleukin 1alpha (IL-1alpha) and tumor necrosis factor alpha (TNF-alpha) contributes to gut GVHD pathogenesis. To help characterize whether human gut GVHD has similar biological characteristics, monocyte IL-1alpha and TNF-alpha production were evaluated after HSCT.

METHODS

Patients with refractory hematologic malignancy (n = 17) underwent reduced-intensity conditioning, HLA-matched sibling HSCT, and cyclosporine A GVHD prophylaxis. After HSCT, monocyte IL-1alpha and TNF-alpha levels were measured using intracellular flow cytometry (IC-FCM), and results were correlated with clinical GVHD.

RESULTS

Incidences of acute GVHD were none (n = 3), grades I-II (n = 9), or grades III-IV (n = 5; each case with stage 2-3 gut GVHD). Posttransplantation monocyte IL-1alpha production (percentage of CD14(+)IL-1(+) cells) increased significantly from 8.7% +/- 3.7% (week 2) to 40.3% +/- 7.3% (week 4; P = 0.0065) and was not associated with GVHD severity (P = 1.00). Conversely, increases in monocyte TNF-alpha were quantitatively reduced and temporally delayed, from 0.6% +/- 0.2% (week 2) to 3.6% +/- 1.4% (week 6; P = 0.076). Most importantly, elevation of monocyte TNF-alpha level correlated with increased gut GVHD severity (P = 0.0041); increases in monocyte TNF-alpha levels typically preceded the onset of gut GVHD symptoms.

CONCLUSIONS

Human gut GVHD after reduced-intensity allogeneic HSCT is associated with monocyte cytokine secretion initially involving IL-1alpha, followed by TNF-alpha. Serial measurement of monocyte cytokines, in particular, TNF-alpha, by IC-FCM may represent a noninvasive method for GVHD monitoring, potentially allowing the identification of patients appropriate for early-intervention strategies.

Graft-versus-host disease is associated with a lower relapse incidence after hematopoietic stem cell transplantation in patients with acute lymphoblastic leukemia

To determine the graft-versus-leukemia effect after hematopoietic stem cell transplantation (HSCT), we studied 199 patients with acute lymphoblastic leukemia who underwent transplantation at Huddinge University Hospital between 1981 and 2001. Seventy-four patients were in first complete remission (CR1), and 125 were in later stages of the disease. Most patients had an HLA-identical sibling donor. Conditioning consisted mainly of total body irradiation and cyclophosphamide, and graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate. Acute GVHD developed in 143 patients and chronic GVHD in 67. The 5-year probability of relapse and relapse-free survival (RFS) were 32% and 49%, respectively, in patients in CR1, as compared with 53% and 33% in those with more advanced disease. In the multivariate risk factor analysis of relapse, we found that the absence of chronic GVHD (P<.001), absence of herpes simplex virus infection after HSCT (P=.003), combination prophylaxis with methotrexate and cyclosporine (P=.01), and >6 weeks from the diagnosis to CR (P=.025) were independent risk factors for relapse after HSCT. Factors associated with a better relapse-free survival were chronic GVHD (P<.001), ABO blood group mismatch (P=.006), younger patient age (P=.01), and an HLA-matched donor (P=.01). The association between herpes simplex virus infection and a low frequency of relapse is a new observation and may indicate that viral antigens play a role in the induction of an antileukemic effect.

Acute and chronic graft-versus-host disease after ablative and nonmyeloablative conditioning for allogeneic hematopoietic transplantation

In this study, we evaluated the influence of nonmyeloablative and ablative conditioning regimens on the occurrence of acute and chronic graft-versus-host disease (GVHD). One hundred thirty-seven patients undergoing matched-related sibling transplantations received the same GVHD prophylaxis. Myeloablative regimens included intravenous busulfan/cyclophosphamide (n=45) and fludarabine/melphalan (n=29). Patients in the nonmyeloablative group (n=63) received fludarabine/idarubicin/cytarabine, cisplatin/fludarabine/idarubicin, and fludarabine/cyclophosphamide. The actuarial rate of grade II to IV acute GVHD was significantly higher (hazard ratio, 3.6; 95% confidence interval, 1.5-8.8) in patients receiving ablative regimens (36%) compared with the nonmyeloablative group (12%). The cumulative incidence of chronic GVHD was higher in the ablative group (40%) compared with the nonmyeloablative group (14%). The rates were comparable within the first 200 days and were significantly higher in the ablative group beyond day 200 (hazard ratio, 5.2; 95% confidence interval, 1.2-23.2). Nonrelapse and GVHD-related mortality were relatively low in both groups. The use of the described nonmyeloablative preparative regimens was associated with a reduced incidence of grade II to IV acute GVHD and chronic GVHD compared with the busulfan/cyclophosphamide and fludarabine/melphalan transplant regimens. It is interesting to note that nonrelapse mortality with nonmyeloablative regimens in older and more debilitated patients was low (14%) and comparable to that achieved with standard high-dose regimens in younger patients.

Successful treatment with nonmyeloablative allogeneic hematopoietic stem cell transplantation in a patient with acute myeloid leukemia complicated with pulmonary infection

We describe the case of a 48-year-old man with acute myeloid leukemia complicated with pulmonary infection that was successfully treated by nonmyeloablative allogeneic peripheral blood stem cell transplantation with conditioning by low-dose total body irradiation and fludarabine. The disease was diagnosed immunophenotypically as myeloid/natural killer cell precursor acute leukemia. After two courses of induction therapy, complete remission was achieved. However, the patient developed pneumonia from prolonged severe neutropenia. Nonmyeloablative allogeneic transplantation was performed because of the active pulmonary infection and the patient's poor performance status. Myelosuppression after transplantation was mild, and the pulmonary infiltration was well controlled during the course of treatment. At the time of this report the patient was an outpatient in our clinic, and on day 500, his disease was in remission with well-controlled chronic graft-versus-host disease. Nonmyeloablative transplantation may provide a new therapeutic strategy for treating patients with active infection who cannot tolerate conventional transplantation with high-dose chemoradiotherapy.

Long-term follow-up of idiotype vaccination in human myeloma as a maintenance therapy after high-dose chemotherapy

The aim of this work was to evaluate the long-term immunological and clinical impact of idiotype (Id) vaccination in multiple myeloma (MM) patients in first remission after high-dose chemotherapy. A total of 15 patients received a series of subcutaneous (s.c.) injections of autologous Id, conjugated to keyhole limpet hemocyanin (KLH) and in association with low doses of GM-CSF. The median duration of follow-up was 110 months from diagnosis. The vaccine induced immune responses that lasted almost 2 years after the end of treatment. Antibody responses included anti-KLH IgM and IgG (90% of patients), anti-KLH IgE (30%), anti-GM-CSF IgG (20%), anti-Id IgG (20%), and anti-Id IgE (30%). Id-specific delayed type hypersensitivity skin tests were positive in 85% of tested patients. Following vaccination, a progressive recovery of T-cell receptor (TCR) diversity was observed and the loss of oligoclonality was significantly correlated with the remission duration. Although Id/KLH conjugates did not eliminate the residual tumor burden, the median progression-free survival, and overall survival were 40 and 82 months, respectively. A retrospective case-matched analysis showed similar results in patients treated with IFN-alpha alone or in association with steroids. This vaccine formulation can overcome Id-specific immune tolerance by inducing clinical responses that are worthy of further investigation.

A myeloablative allograft after rejection of two consecutive nonmyeloablative transplants from two different HLA identical siblings

A 55-year-old female with standard risk AML in second CR received an allogenic transplant from an HLA-matched sibling, using a nonmyeloablative conditioning regimen (NMST). On day +139, she rejected her graft with autologous reconstitution. She received a second NMST from a different HLA-matched sibling with an identical conditioning regimen and immunosuppression. On day +110, she rejected the second graft, with autologous reconstitution with blasts. She received a third allograft from the first sibling with a myeloablative busulfan-based conditioning regimen. She is now day +270, in CR, with full donor chimerism.

Graft-versus-leukemia reactions in allogeneic chimeras

There is a strong graft-versus-leukemia (GVL) effect of allogeneic stem cell transplantation (SCT) due to elimination of tumor cells by alloimmune effector lymphocytes. When leukemia relapses after allogeneic SCT, donor lymphocyte transfusions (DLTs) can induce sustained remissions in some patients. This review summarizes the current status on clinical use of DLT, the basis of GVL reactions, problems associated with this therapy, and new strategies to improve DLT. Several multicenter surveys demonstrated that the GVL effect of DLT is most effective in chronic myelogenous leukemia (CML), whereas it is less pronounced in acute leukemia and myeloma. Cytokine stimulation to induce differentiation of myeloid progenitor cells or to up-regulate costimulatory molecules on tumor cells may improve the efficacy of DLT. Infections and graft-versus-host disease (GVHD) are major complications of DLT. Control of GVHD may be improved using suicide gene-modified T cells for DLT, allowing T-cell elimination if severe GVHD develops. Hopefully, in the future, GVL effect can be separated from GVHD through adoptive transfer of selected T cells that recognize leukemia-specific antigens or minor histocompatibility antigens, which are expressed predominantly on hematopoietic cells, thereby precluding attack of normal tissues. In patients with leukemia and lymphomas with fast progression, tumor growth may outpace development of effector T cells. Here it may be preferable to select stem cell transplant donors with HLA-mismatches that allow alloreactive natural killer cells, which appear early after transplantation, to retain their cytolytic function. New approaches for adoptive immune therapy of leukemia, which promise a better prognosis for these patients, are being developed.

Nonmyeloablative reduced-intensity transplantation in multiple myeloma

Reduced-intensity conditioning (RIC) allogeneic transplants are being performed more frequently in a variety of hematologic malignancies. The aim is to exploit the graft-versus-tumor (GVT) effect seen after allografting without the toxicities of myeloablative conditioning. RIC regimens are being extensively explored for salvage therapy of myeloma. Although nonrelapse mortality rates are acceptable, relapse remains the most common cause of treatment failure. New combinations and novel therapies need to be explored to improve outcomes. This strategy should also be employed earlier in the course of the disease.

Adoptive immunotherapy with donor lymphocyte infusions after allogeneic hematopoietic cell transplantation following nonmyeloablative conditioning

This study retrospectively analyzed data from 446 patients given hematopoietic cell transplants from HLA-matched related or unrelated donors after conditioning with 2 Gy total body irradiation with or without fludarabine and postgrafting immunosuppression with mycophenolate mofetil and cyclosporine following grafting. Fifty-three of 446 patients received donor lymphocyte infusion (DLI) with a median CD3 dose of 1 × 107 cells/kg. Their diagnoses included myelodysplastic syndrome (n = 10), acute leukemia (n = 10), chronic leukemia (n = 11), multiple myeloma (n = 9), lymphoma (n = 9), and solid tumors (n = 4). Patients received DLI for persistent disease (n = 8), disease relapse (n = 17), progressive disease (n = 12), low donor chimerism with disease (n = 11), or low chimerism with disease remission (n = 5). Seventeen of the 53 patients (32%) are alive with a median follow-up of 30 months; 5 are in complete remission (CR), 2 are in partial remission (PR), and 10 have stable or progressive disease. Nine of 53 patients (17%) developed grades II to IV acute graft-versus-host disease. Of 48 patients receiving DLI for treatment of disease, 7 achieved CR and 5 PR, with an overall response rate of 25%. Six of 16 patients who received DLI for chimerism had increases in donor chimerism leading to sustained engraftment, whereas 10 eventually rejected their grafts. In conclusion, DLI is a potential treatment strategy, with acceptable toxicity, for patients with persistent, relapsed, or progressive disease after nonmyeloablative hematopoietic cell transplantation.

Immunoablative reduced-intensity stem cell transplantation: potential role of donor Th2 and Tc2 cells

Allogeneic reduced-intensity stem cell transplantation (RISCT) decreases regimen-associated morbidity and mortality, but it is unfortunately still constrained by the same immune T-cell reactions that limit myeloablative transplantation, including graft rejection, graft-versus-host disease (GVHD), and suboptimal graft-versus-leukemia (GVL) or graft-versus-tumor (GVT) effects. Graft rejection is mediated by host T cells, whereas GVHD and GVL/GVT effects are initiated by donor T cells, and to this extent, future advances in RISCT will likely benefit from an ability to modulate both donor and host T-cell immunity. As a step in this direction, we have developed a RISCT approach that first involves chemotherapy-induced host T-cell ablation, and second involves administration of allogeneic inocula enriched for donor CD4(+) Th2 and CD8(+) Tc2 T-cell subsets that in murine studies mediate reduced GVHD. In a pilot clinical trial, "immunoablative" RISCT with human leukocyte antigen (HLA)-matched related allografts resulted in rapid and complete donor chimerism and GVL effects early post-transplant, with GVHD being the primary toxicity. Using this immunoablative RISCT approach, we are now evaluating the feasibility and safety of augmenting allografts with additional donor CD4(+) Th2 cells that are generated in vitro via CD3/CD28 costimulation in the presence of interleukin (IL)-4. We review the biology of host and donor T-cell immunity during allogeneic RISCT and discuss the strategies of host immunoablation and donor Th2 and Tc2 cell therapy as potential means to improve the clinical results in RISCT.

A pilot study of reduced intensity conditioning and allogeneic stem cell transplantation from unrelated cord blood and matched family donors in children and adolescent recipients

Reduced intensity (RI) allogeneic stem cell transplantation (AlloSCT) was initially demonstrated in adults following HLA-matched family and unrelated adult donor AlloSCT. There is little information about RI AlloSCT in children. We report results of a pilot study of RI AlloSCT in 21 recipients (< or =21 years). Age: median 13 (0.5-21) years, 8F:13M, 14 unrelated cord blood units (UCB) (10 4/6, 4 5/6), two related BM (6/6, 5/6), four related PBSC (2 6/6, 2 5/6), and one related BM+PBSC (6/6). RI: fludarabine, busulfan (n=14); fludarabine, cyclophosphamide (n=4); fludarabine, melphalan (n=1); total body irradiation, fludarabine, cyclophosphamide (n=1); or fludarabine, cyclophosphamide, and etoposide (n=1). Graft-versus-host disease prophylaxis: FK506 0.03 mg/kg/day and mycophenolate mofetil 15 mg/kg/q 12 h. UCB median nuc/kg and CD34/kg was 4.3 x 10(7)/kg (0.9-10.8) and 1.9 x 10(5)/kg (0.3-6.9), and related BM/PBSC median nuc/kg and CD34/kg was 8.3 x 10(8) (4.7-18.9) and 5.0 x 10(6)/kg (4.6-6.4). Maximal chimerism following unrelated cord blood transplantation, 100% x 7, 98% x 1, 95% x 2, 55% x 1, and 0% x 3; related PBSC/BM, 100% x 5, 65% x 1, and 55% x 1. Graft failure occurred in 5/21 (24%). In summary, RI AlloSCT in children is feasible and tolerable (< or =25% GF) and results in > or =85% of recipients initially achieving > or =50% donor chimerism.

Impact of unrelated donor status on the incidence and outcome of cytomegalovirus infections after non-myeloablative allogeneic stem cell transplantation

Little is known about the impact of cytomegalovirus (CMV) infections that occur after human leucocyte antigen (HLA)-matched unrelated donor (MUD) non-myleoablative haematopoietic stem cell transplantation (HCT). We analysed the incidence, onset and outcomes of CMV infections in 59 recipients of MUD and in 109 recipients of HLA-matched related donor (MRD) allogeneic HCT following non-myeloablative conditioning containing 2 Gy total body irradiation and fludarabine. In CMV seropositive recipients, antigenaemia occurred in 68% (MUD) and in 49% (MRD, P = 0.08); there were no differences in the maximum levels of CMV antigenaemia and the time to cessation with antiviral therapy. CMV viraemia by culture was more common in MUD compared with MRD HCT recipients in univariate analysis (26% vs. 6%, P = 0.01), however, this difference was not detectable after controlling for other factors. The rates of CMV disease in the first 100 d were similar in MUD (9%) and MRD (5%) HCT recipients. CMV disease tended to occur earlier in the MUD compared with the MRD recipients (median day 41 vs. day 80). Beyond day 100, rates of CMV disease remained similar in both cohorts (cumulative incidence: MUD 21% and MRD 14%). The 30-d and 1-year survivals after CMV disease diagnosis were not significantly different in both groups. Thus, there appeared to be a trend toward increased CMV reactivation in MUD compared with MRD non-myeloablative allogeneic HCT recipients; however, these differences did not reach statistical significance in this cohort and preemptive therapy was similarly effective in preventing CMV diseases.

Hepatic injury after nonmyeloablative conditioning followed by allogeneic hematopoietic cell transplantation: a study of 193 patients

Liver injury is a frequent, serious complication of allogeneic hematopoietic cell transplantation (HCT) following myeloablative preparative regimens. We sought to determine the frequency and severity of hepatic injury after nonmyeloablative conditioning and its relationship to outcomes. One hundred ninety-three consecutive patients who received 2 Gy total body irradiation with or without fludarabine were evaluated for end points related to liver injury. Patients with diseases treatable by HCT who were ineligible for conventional myeloablative allogeneic HCT because of advanced age and/or comorbid conditions were included. Fifty-one patients (26%) developed hyperbilirubinemia of 68.4 microM (4 mg/dL) or greater, most commonly resulting from cholestasis due to graft-versus-host disease (GVHD) or sepsis. Pretransplantation factors associated with liver dysfunction were a diagnosis of aggressive malignancy (hazard ratio [HR] 1.9; P =.04) and the inclusion of fludarabine in the conditioning regimen (HR 1.8; P =.07). Overall survival at 1 year was superior for patients who had maximal serum bilirubin levels in the normal (78%) or minimally elevated (22.23-66.69 microM [1.3-3.9 mg/dL]) ranges (69%) compared with those in the 68.4 to 117.99 microM (4-6.9 mg/dL; 20%), 119.7 to 169.29 microM (7.0-9.9 mg/dL; 17%), and 171.0 microM (10 mg/dL; 19%) or greater groups. In summary, significant jaundice occurred in 26% of patients and was predominantly due to cholestasis resulting from GVHD and/or sepsis. Aggressive malignancies (mainly advanced disease) and later development of jaundice after transplantation predicted inferior survival.

Development of early neutropenic fever, with or without bacterial infection, is still a significant complication after reduced-intensity stem cell transplantation

Little information is available on the clinical characteristics of infectious complications that occur in the early period after reduced-intensity stem cell transplantation (RIST). We retrospectively investigated the clinical features of neutropenic fever and infectious episodes within 30 days after RIST in 76 patients who had received fluoroquinolones as part of their antibacterial prophylaxis. Preparative regimens included cladribine 0.66 mg/kg or fludarabine 180 mg/m2 plus busulfan 8 mg/kg. All but 1 patient survived 30 days after transplantation, and 75 patients (99%) became neutropenic within a median duration of 9 days. Neutropenic fever was observed in 29 patients (38%), and bacterial infection was confirmed in 15 (20%) of these, including bacteremia (n = 13), bacteremia plus pneumonia (n = 1), and urinary tract infection (n = 1). The causative organisms were gram-positive (n = 9) and gram-negative organisms (n = 7), with a mortality rate of 6%. Neither viral nor fungal infection was documented. Multivariate analysis showed that the presence of neutropenia at the initiation of preparative regimens was an independent risk factor for subsequent documented bacterial infections (P =.026; 95% confidence interval, 1.25-35.1). We conclude that neutropenic fever and bacteremia remain common complications in RIST.

Female donors contribute to a selective graft-versus-leukemia effect in male recipients of HLA-matched, related hematopoietic stem cell transplants

Male recipients of transplants from female (F-->M) hematopoietic stem cell donors represent a special group in whom donor T cells that are specific for recipient minor histocompatibility antigens encoded by Y-chromosome genes may contribute to a graft-versus-leukemia (GVL) effect and to graft-versus-host disease (GVHD). We examined the contribution of donor/patient sex to the risk for relapse and GVHD in 3238 patients who underwent HLA-identical sibling hematopoietic stem cell transplantation (HSCT) for hematopoietic malignancies at a single institution. Compared with other sex combinations, male recipients of female transplants had the lowest risk for relapse and the greatest odds for GVHD. Remarkably, after controlling for GVHD as a time-dependent covariate, F-->M HSCT still exhibited a lower risk for relapse than other sex combinations, demonstrating a selective GVL effect distinct from that contributed by GVHD. A reduction in relapse after F-->M HSCT was observed in patients with chronic myelogenous leukemia (CML), acute myelogenous leukemia (AML), and acute lymphoblastic leukemia (ALL). Taken together, these data suggest that minor H antigens encoded or regulated by genes on the Y chromosome contribute to a selective GVL effect against myeloid and lymphoid leukemias after F-->M HSCT.

Acute graft-versus-host disease in patients with Fanconi anemia or acquired aplastic anemia undergoing bone marrow transplantation from HLA-identical sibling donors: risk factors and influence on outcome

To assess whether Fanconi anemia (FA) patients might be at risk for acute graft-versus-host disease (AGvHD) despite using low-intensity conditionings, we retrospectively analyzed the incidence of AGvHD and its impact on outcome in 37 FA patients and 73 patients with acquired aplastic anemia (AAA) that received transplants at Saint Louis Hospital from HLA-genotypic identical siblings with similar conditionings (thoraco-abdominal irradiation plus cyclophosphamide 20 [FA] or 150 mg/kg [AAA]). Despite being younger, FA patients had an increased risk of grades II to IV AGvHD (relative risk [RR], 2.00; P =.021), especially in younger patients (RR, 7.93; P =.014). The risks of requiring systemic corticosteroids to treat AGvHD and experiencing cortico-resistant AGvHD were significantly increased in FA patients. Although non-FA and FA patients had similar 10-year outcomes, acute and chronic GvHD had a biphasic effect on FA patient outcome with an additional cluster of lethal events starting by 5 years after transplantation. This late survival fall, restricted to FA patients, was closely related to head and neck carcinomas (15-year incidence: 53%). FA patients represent a group at risk regarding AGvHD when using irradiation-based conditionings. The impact of AGvHD on survival may not be limited to the early posttransplantation period and may be a major risk factor for head and neck carcinomas and late mortality in FA patients.

Will developments in allogeneic transplantation influence treatment of adult patients with sickle cell disease?

With improvements in the treatment of children with sickle cell disease (SCD), there has been a significant increase in the number of patients with SCD in adult hematology practice. Quality of life and life expectancy continue to be severely compromised in adult patients; hydroxyurea is the only treatment currently available that could reduce the severity and frequency of painful episodes. Allogeneic stem cell transplantation (SCT) has been offered to children with SCD as a curative option. We discuss the implications of new developments in the field of allogeneic SCT in the treatment of adult SCD patients in light of the experience derived from pediatric transplantation. These developments include innovations in the conditioning regimens, GVHD prophylaxis, and alternative donor SCT and their possible effect on adult SCD patients. Finally, we discuss a nonmyeloablative conditioning protocol for adult SCD patients and the eligibility criteria for adult SCD patients undergoing allogeneic transplantation.

T-cell reconstitution after unmanipulated, CD8-depleted or CD34-selected nonmyeloablative peripheral blood stem-cell transplantation

BACKGROUND

We have previously shown that CD8 depletion or CD34 selection of peripheral blood stem cells (PBSC) reduced the incidence of acute graft-versus-host disease (GvHD) after nonmyeloablative stem-cell transplantation (NMSCT). In this study, we analyze the effect of CD8 depletion or CD34 selection of the graft on early T-cell reconstitution.

METHODS

Nonmyeloablative conditioning regimen consisted in 2 Gy total-body irradiation (TBI) alone, 2 Gy TBI and fludarabine, or cyclophosphamide and fludarabine. Patients 1 to 18 received unmanipulated PBSC, patients 19 to 29 CD8-depleted PBSC, and patients 30 to 35 CD34-selected PBSC.

RESULTS

T-cell counts, and particularly CD4+ and CD4CD45RA+ counts, remained low the first 6 months after nonmyeloablative stem-cell transplantation (NMSCT) in all patients. CD34 selection (P<0.0001) but not CD8 depletion of PBSC significantly decreased T-cell chimerism. Donor T-cell count was similar in unmanipulated compared with CD8-depleted PBSC recipients but was significantly lower in CD34-selected PBSC recipients (P=0.0012). T cells of recipient origin remained stable over time in unmanipulated and CD8-depleted PBSC patients but expanded in some CD34-selected PBSC recipients between day 28 and 100 after transplant. Moreover, whereas CD8 depletion only decreased CD8+ counts (P<0.047), CD34 selection reduced CD3+(P<0.001), CD8+(P<0.016), CD4+ (P<0.001), and CD4+CD45RA+ (P<0.001) cell counts. T-cell repertoire was restricted in all patients on day 100 after hematopoietic stem-cell transplantation but was even more limited after CD34 selection (P=0.002).

CONCLUSIONS

Despite of the persistence of a significant number of T cells of recipient origin, T-cell counts were low the first 6 months after NMSCT. Moreover, contrary with CD8 depletion of the graft that only affects CD8+ lymphocyte counts, CD34 selection dramatically decreased both CD8 and CD4 counts.

Nonmyeloablative stem cell transplantation with fludarabine and cyclophosphamide for patients with hematologic malignancies

We conducted a multi-center phase I/II trial of nonmyeloablative stem cell transplantation for patients with hematologic malignancies. The aim of this trial was to assess the safety and feasibility of this treatment modality for older or younger patients with significant organ dysfunction, who could not be treated with conventional high dose chemoradiotherapy. Twelve patients were treated with a conditioning regimen consisting of fludarabine and cyclophosphamide, followed by peripheral blood stem cell transplantation from human leukocyte antigen (HLA) identical siblings. Nonhematologic toxicities were mild. Median time to absolute neutrophils above 0.5 x 10(9)/l, 1.0 x 10(9)/l and platelets above 50 x 10(9)/l were 8, 10 and 12 days, respectively. Donor dominant hematopoiesis was achieved in all patients, with or without donor leukocyte infusion. The cumulative incidence of acute and chronic graft-versus-host disease (GVHD) was 75 and 56%, respectively. Only one patient experienced early death within 100 days, caused by acute GVHD complicated by fungal infection. All patients except one achieved complete remission. With a median follow-up of 330 days, expected progression-free survival is 75%. Overall survival is 76%. Our study confirms that nonmyeloablative stem cell transplantation with cyclophosphamide and fludarabine conditioning is a safe and promising treatment for elderly patients with hematologic malignancies. A further study in large-scale setting is warranted.

Hematopoietic cell transplantation: five decades of progress

During the past 50 years, the role of allogeneic hematopoietic cell transplantation (HCT) has changed from a desperate therapeutic maneuver plagued by apparently insurmountable complications to a curative treatment modality for thousands of patients with hematologic diseases. Now, cure rates following human leukocyte antigen (HLA) allogeneic HCT with matched siblings exceed 85% for some otherwise lethal diseases, such as chronic myeloid leukemia, aplastic anemia, or thalassemia. In addition, the recent development of non-myeloablative conditioning and stem cell transplantation has opened the way to include elderly patients with a wide variety of hematologic malignancies. Further progress in adoptive transfer of T cell populations with relative tumor specificity would make the transplant procedure more effective and would extend the use of allogeneic HCT for treatment of non-hematopoietic malignancies.

Strategies to reduce transplant-related mortality after allogeneic stem cell transplantation in elderly patients: Comparison of reduced-intensity conditioning and unmanipulated peripheral blood stem cells vs a myeloablative regimen and CD34+ cell selection

OBJECTIVES

The aim of this study was to compare two approaches used to reduce transplant-related mortality (TRM) after allogeneic peripheral blood stem cell transplantation (allo-PBSCT) in elderly patients.

PATIENTS AND METHODS

Data from 50 patients, 45 years of age or older, consecutively treated with an HLA-identical sibling allo-PBSCT at the Hospital de Sant Pau were analyzed. We have compared the outcome of patients treated with conventional myeloablative regimens and CD34(+)-selected cells (CD34(+) group; n=23) with those receiving reduced-intensity conditioning regimens, consisting of fludarabine (150 mg/m(2)) plus an alkylating agent, followed by unmanipulated grafts (RIC group; n=27). Patient characteristics were well balanced between the two groups, although patients in the RIC group were slightly older.

RESULTS

The incidence of acute graft-vs-host disease (GVHD) was similar in both groups. The 1-year cumulative incidence of extensive chronic GVHD was 38% in the RIC group and 17% in the CD34(+) group (p=0.2). After a median follow-up of 28 months, there were no differences in the relapse rate. Patients in the RIC group had a lower TRM, with a cumulative incidence of 7% vs 30% at 6 months and 15% vs 39% at 1 year (p=0.05). The Kaplan-Meier estimates of PFS at 2 years was 67% in the RIC group and 43% in the CD34(+) group (p=0.09) and the OS was 69% vs 43% (p=0.05), respectively.

CONCLUSION

CD34(+) cell selection reduced the risk of extensive cGVHD but was associated with a higher TRM. Although the number of patients is limited, our study suggests that this approach should be restricted to relatively young patients, as better outcomes can be achieved in elderly patients using RIC strategies.

Infectious complications following allogeneic HLA-identical sibling transplantation with antithymocyte globulin-based reduced intensity preparative regimen

In the setting of reduced-intensity conditioning (RIC) regimens for allogeneic stem cell transplantation (allo-SCT), the epidemiology of transplant-related infections is still poorly defined. In 101 high-risk patients who received an HLA-identical sibling allo-SCT after RIC, including fludarabine, busulfan and antithymocyte globulin (ATG), we report during the first 6 months a cumulative incidence of positive CMV antigenemia of 42% (95% CI 32-52%), developing at a median of 37 (range 7-116) days without evidence of CMV disease (median follow-up, 434 days). The cumulative incidence of bacteremia was 25% (95% CI 17-33%), occurring at a median of 67 (range 7-172) days, while patients had recovered a full neutrophil count. In all, 65% of the bacteremia (95% CI 49-81%) were gram negative. The cumulative incidence of fungal infections was 8% (95% CI 3-13%), with a median onset of 89 (range 7-170) days. In multivariate analysis, stem cell source (bone marrow; P=0.0002) was significantly associated with the risk of positive CMV antigenemia, while higher doses of prednisone (>2 mg/kg) represented the major risk factor for bacteremia (P=0.0001). Infectious-related mortality was 5% (95% CI 1-9%), with aspergillosis being the principal cause. Collectively, these results suggest that prospective efforts are warranted to develop optimal antimicrobial preventive strategies after RIC allo-SCT.

Allografting with nonmyeloablative conditioning following cytoreductive autografts for the treatment of patients with multiple myeloma

The full potential of a graft-versus-myeloma effect after allogeneic hematopoietic cell transplantation (HCT) for patients with multiple myeloma (MM) has not been realized because of excessive early transplantation-related mortality (TRM) with conventional HCT. Autologous HCTs have been characterized by almost universal disease recurrences. The current trial combined autologous HCT with subsequent nonmyeloablative allogeneic HCT to maintain the benefits of both approaches with acceptable toxicity. Fifty-four patients, 52 years of age (median; range, 29-71 years), with previously treated stage II or III MM (52% refractory or relapsed disease) were given melphalan 200 mg/m2 and autologous HC transplants. Regimen-related toxicities after autologous HCT were moderate with a median of 6 days of neutropenia, 7 days of hospitalization, and 1 death from infection. Forty to 229 days later (median, 62 days), 52 patients received a single fraction dose of 2 Gy total body irradiation and HC transplants from HLA-identical siblings with postgrafting immunosuppression with mycophenolate mofetil (MMF) and cyclosporine (CSP). Patients experienced medians of 0 days of hospitalization, neutropenia, and thrombocytopenia. Sustained engraftment was uniform. With a median follow-up of 552 days after allografting, overall survival is 78%. One patient (2%) died before day 100 from disease progression. Thirty-eight percent of patients developed acute graft-versus-host disease (GVHD; grade II in all but 4 cases) and 46% chronic GVHD requiring therapy. Tumor responses occurred slowly. Thus far, 57% of patients have achieved complete remissions and 26% have achieved partial remissions for an overall response of 83%. Despite being evaluated in elderly patients with MM, this 2-step approach has reduced the acute toxicities of allogeneic HCT while achieving potent antitumor activities.

Risks and outcomes of idiopathic pneumonia syndrome after nonmyeloablative and conventional conditioning regimens for allogeneic hematopoietic stem cell transplantation

Idiopathic pneumonia syndrome (IPS) is a significant noninfectious complication of hematopoietic stem cell transplantation (HSCT). We compared the incidences and outcomes of IPS among patients who underwent allogeneic HSCT after nonmyeloablative (n = 183) compared with conventional (n = 917) conditioning between December 1997 and December 2001. Patients given nonmyeloablative conditioning were older than those given conventional conditioning (median ages, 53 vs 41 years; P =.001). The cumulative incidence of IPS was significantly lower at 120 days after nonmyeloablative conditioning than conventional conditioning (2.2% vs 8.4%; P =.003). In addition, greater patient age (older than 40 years), diagnosis of acute leukemia or myelodys-plastic syndrome, and severe acute graft-versus-host disease were associated with significantly increased risks for IPS. Among older patients (older than 40 years) given conventional conditioning, high-dose total body irradiation (TBI) was associated with an increased risk for IPS than were non-TBI-based regimens (16% vs 5.8%; P =.001). IPS occurred early after transplantation, progressed rapidly, and was associated with a high mortality rate (75%) despite aggressive support. Initiation of mechanical ventilation and the presence of renal insufficiency at IPS onset were associated with increased risks for death after IPS. These findings support the concept that lung damage from the conditioning regimen plays a crucial role in the development of IPS after HSCT.

Reduced-intensity conditioning for unrelated donor hematopoietic stem cell transplantation as treatment for myeloid malignancies in patients older than 55 years

Hematopoietic stem cell transplantation from unrelated donors is an effective treatment for myeloid malignancies, but its use is usually restricted to young patients without comorbidities. The development of reduced-intensity preparative regimens has allowed the extension of this form of treatment to older and medically infirm patients. We assessed the outcomes of patients older than 54 years who received unrelated donor transplants for the treatment of myeloid malignancies in our institution. There were 29 patients (median age, 59 years) with advanced acute myeloid leukemia (n = 13), myelodysplastic syndrome (n = 7), and chronic myeloid leukemia (n = 9) included. With a median follow-up of 27 months, the probability of overall and event-free survival, and nonrelapse mortality at one year were 44%, 37%, and 55%, respectively. Grades II to IV acute graft-versus-host disease (GVHD) occurred in 41% of patients and chronic GVHD developed in 63% of patients surviving more than 100 days. Of the 11 survivors, 9 were interviewed and reported good quality of life after transplantation using the Functional Assessment of Cancer Therapy-Bone Marrow Transplant Scale (FACT-BMT) questionnaire, with high scores in all dimensions. Unrelated donor transplantation is a treatment option for older patients with myeloid malignancies. The results in this cohort of patients are comparable with those reported in younger patients with similarly advanced disease.

Prior chemotherapy and allograft CD34+ dose impact donor engraftment following nonmyeloablative allogeneic stem cell transplantation in patients with solid tumors

Significant engraftment variability occurs among patients following nonmyeloablative hematopoietic cell transplantation. We analyzed the impact of multiple factors on donor myeloid and T-cell engraftment in 36 patients with metastatic tumors undergoing cyclophosphamide/fludarabine-based conditioning. Higher CD34(+) doses facilitated donor myeloid engraftment, while prior chemotherapy exposure facilitated both donor myeloid and T-cell engraftment. At day 30, median donor T-cell and myeloid chimerism was 98% and 76%, respectively, in those patients with prior chemotherapy versus 88% (P =.008) and 26% (P <.0001) in chemotherapy-naive patients. Donor myeloid chimerism at day 45 was predicted by prior chemotherapy exposure and the log(10) of the CD34(+) dose (adjusted coefficient of determination [R(2)] =.47; P <.0001), while chemotherapy alone impacted donor T-cell engraftment. Patients with prior chemotherapy were more likely to develop acute grades II to IV graft-versus-host disease (GVHD; 8/18) compared with chemotherapy-naive patients (2/18; P =.031). Thus, tailoring the intensity of nonmyeloablative conditioning based on prior chemotherapy exposure is an important consideration in trial design.

Cytomegalovirus infections in allogeneic stem cell recipients after reduced-intensity or myeloablative conditioning assessed by quantitative PCR and pp65-antigenemia

Since the incidence of cytomegalovirus (CMV) infections after hematopoietic stem cell transplantation (HSCT) may depend on the intensity of the pretreatment, we studied the incidence of CMV infections after reduced-intensity compared to myeloablative conditioning. A total of 82 patients with matched related or unrelated donors were prospectively monitored for CMV infections after HSCT by CMV-PCR techniques, CMV-antigenemia and clinical observation. A total of 45 patients received reduced-intensity conditioning consisting of fludarabine, busulfan and ATG and 37 patients received myeloablative conditioning. Leukocyte engraftment occurred after a median of 15 vs 18 days (P=0.012) and platelet engraftment after 12 days vs 20 days (P=0.001), respectively. Acute graft-versus-host disease (GVHD) grade II-IV was observed in 58 vs 54% patients (P=0.737), respectively. The onset and peak values of CMV-antigenemia and DNAemia and the incidence of CMV infections did not differ statistically significantly between the two treatment groups. Multivariate analysis confirmed CMV seropositivity of the recipient (P=0.035), acute GVHD II-IV (P=0.001) but not the type of conditioning as significant risk factors for CMV-antigenemia. In conclusion, the kinetics of CMV-antigenemia and DNAemia and the incidence of CMV infections were not statistically different in patients who received HSCT after reduced-intensity conditioning with fludarabine, busulfan and ATG compared to myeloablative conditioning.

Reduced-intensity allogeneic stem cell transplantation for patients whose prior autologous stem cell transplantation for hematologic malignancy failed

Autologous hematopoietic stem cell transplantation (autoSCT) is an effective treatment for patients with various hematologic malignancies. Despite the significant improvement in the overall outcome, disease progression after transplantation remains the major cause of treatment failure. With longer follow-up, therapy-related myelodysplasia/acute myelogenous leukemia is becoming an important cause of treatment failure. The prognosis for these 2 groups of patients is very poor. Allogeneic hematopoietic stem cell transplantation (alloSCT) is a potential curative treatment for these patients. However, the outcome with conventional myeloablative alloSCT after failed autoSCT is typically poor because of high transplant-related mortality. In an attempt to reduce the treatment-related toxicity, we studied a reduced-intensity conditioning regimen followed by alloSCT for patients with progressive disease or therapy-related myelodysplasia/acute myelogenous leukemia after autoSCT. This report describes the outcomes of 28 patients with hematologic malignancies who received a reduced-intensity alloSCT after having treatment failure with a conventional autoSCT. Fourteen patients received a hematopoietic stem cell transplant from a related donor and 14 from an unrelated donor. The conditioning regimen consisted of low-dose (2 Gy) total body irradiation with or without fludarabine in 4 patients and the combination of melphalan (140 mg/m(2)) and fludarabine in 24. Cyclosporine and mycophenolate mofetil were used for posttransplantation immunosuppressive therapy, as well as graft-versus-host disease (GVHD) prophylaxis, in all patients. All patients engrafted and had >90% donor chimerism on day 100 after SCT. Currently, 13 patients (46%) are alive and disease free, 7 patients (25%) developed disease progression after alloSCT, and 8 (32%) died of nonrelapse causes. Day 100 mortality and nonrelapse mortality were 25% and 21%, respectively. With a median follow-up of 24 months for surviving patients, the 2-year probabilities of overall survival, event-free survival, and relapse rates were 56.5%, 41%, and 41.9%, respectively. Six patients (21%) developed grade III to IV acute GVHD. Among 21 evaluable patients, 15 (67%) developed chronic GVHD. We conclude that (1) reduced-intensity alloSCT is feasible and has an acceptable toxicity profile in patients who have previously received autoSCT and that (2) although follow-up was short, a durable remission may be achieved in some patients who would otherwise be expected to have a poor outcome.

Low-dose total-body irradiation and fludarabine followed by hematopoietic cell transplantation from HLA-identical sibling donors do not induce complete T-cell donor engraftment in most patients with progressive hematologic diseases

OBJECTIVE

The aim of this study was to determine whether nonmyeloablative transplants (NMT) result in complete and sustained donor engraftment in patients with progressive hematologic diseases compared to patients with stable disease or who are in remission.

MATERIALS AND METHODS

We prospectively monitored the kinetics of engrafting of T cells and myeloid cells in 10 consecutive adult patients with hematologic diseases submitted to NMT from an HLA-identical sibling donor. Patients were considered ineligible for conventional allogeneic transplantation because of age, concomitant diseases, or previous autologous transplant. Conditioning regimen and graft-vs-host disease posttransplant prophylaxis consisted of 2-Gy total-body irradiation plus fludarabine 30 mg/m(2)/day for 3 days, and cyclosporin and mycophenolate mofetil, respectively.

RESULTS

One patient died in remission, and eight relapsed or progressed at a median of 68 days (15-335). On day +56, only 1 (11%) of 9 patients analyzed had achieved T-cell complete donor chimerism (CC), whereas 6 (67%) had achieved myeloid CC (p=0.05). Median time for T-cell CC to occur was 110 days (56-150) compared with 42 days (28-100) to achieve myeloid CC (p=0.002). The only parameter associated with T-cell CC was the status of the disease at the time of transplantation. Thus, 5 (100%) of 5 patients with stable disease or who were in remission before the transplant achieved T-cell CC compared with only 1 (20%) of 5 patients with progressive disease (p=0.05).

CONCLUSION

Conditioning regimen based on fludarabine and 2-Gy total-body irradiation allows cell immunotherapy for old and medically infirm patients, but its antitumoral effect in patients with progressive hematologic disease is limited.

Bone marrow as stem cell source for allogeneic HLA-identical sibling transplantation following reduced-intensity preparative regimen

OBJECTIVE

Reduced-intensity conditioning regimens (RIC) and peripheral blood stem cells (PBSC) are increasingly used for allogeneic stem cell transplantation (allo-BMT). RIC has been shown to allow engraftment with minimal early transplant-related mortality (TRM). However, in the context of RIC, the use of bone marrow (BM) as stem cell source is still little evaluated.

PATIENTS AND METHODS

In this report, we analyzed the outcome of 32 high-risk patients with hematological malignancies who received an HLA-identical sibling allo-BMT after RIC including fludarabine, busulfan, and anti-thymocyte globulin (ATG).

RESULTS

Sustained neutrophil and platelet recovery occurred at a median of 13 days (range, 10-19) and 17 days (range, 0-45) respectively. Early and durable full donor chimerism could be established as soon as the first month after allo-BMT. Also, a sustained and early CD8(+) T-cell recovery was observed, but the CD4(+) T-cell compartment remained profoundly low. The cumulative incidences of grade II-IV acute GVHD and chronic GVHD were 26% (95% CI, 11-41%) and 31% (95% CI, 15-47%) respectively. The overall cumulative incidence of TRM was 28% (95% CI, 12-44%) occurring mainly in patients aged over 50. In this setting, GVHD showed a protective effect on disease progression or relapse with better progression-free survival for patients with GVHD as compared to patients without GVHD (p=0.03).

CONCLUSIONS

Collectively, these results confirm that the use of BM grafts for RIC is feasible with durable donor engraftment and no detrimental GVHD.

Allogeneic hematopoietic stem cell transplantation for myeloproliferative disorders and myelodysplastic syndromes

Allogeneic SCT is the most effective method to achieve cure in patients with MPD and MDS. This approach is associated with significant risk of morbidity (eg, GVHD) and TRM, although the incidence and severity vary based on donor and recipient characteristics. For young patients with HLA-matched donors, SCT is the preferred therapy. Efforts to improve outcome for older patients and for patients with alternative donors have led to decreased treatment-associated complications with associated better long-term DFS.

Immunologic recovery after hematopoietic cell transplantation with nonmyeloablative conditioning

OBJECTIVE

We studied immune reconstitution in 51 recipients of HLA-identical hematopoietic cellular transplant (HCT) after nonmyeloablative conditioning compared to a reference group of 67 recipients after myeloablative conditioning.

METHODS

Nonmyeloablative conditioning consisted of 2 Gy total-body irradiation+/-fludarabine and postgrafting cyclosporine and mycophenolate mofetil. All patients received G-CSF-mobilized peripheral blood mononuclear cells. Patients were followed with serial assessments of lymphocyte subset counts, antibody levels, virus-induced lymphoproliferation, and limiting-dilution assays for cytomegalovirus (CMV) T helper (T(H)) cells. Rates of infections over the first year after transplant were calculated.

RESULTS

During the first 180 days, absolute lymphocyte subset counts were similar (except higher total and memory B cell counts on day 80 in nonmyeloablative patients). At 1 year, however, total and naïve CD4 counts, and naïve CD8 counts, were higher in myeloablative patients. The levels of antibodies were similar at all time points and after vaccinations. The function of CD4 cells assessed by virus-induced lymphoproliferation was similar. However, the absolute counts of CMV T(H) cells were higher at days 30 and 90 (p=0.002 and p=0.0003, respectively) after nonmyeloablative conditioning. The rates of definite infections were lower for nonmyeloablative patients during the first 90 days, but were higher later. The higher number of CMV-specific T cells days 30 and 90 after nonmyeloablative HCT coincided with a lower rate of CMV infections during that time.

CONCLUSION

The immunity of nonmyeloablative HCT recipients appears better than the immunity of conventional HCT recipients early, but not late, after HCT.

Relapse or progression after hematopoietic cell transplantation using nonmyeloablative conditioning: effect of interventions on outcome

OBJECTIVE

This study analyzes the effect of interventions aimed at reinducing remissions in patients with relapse or progression of malignant disease following allogeneic hematopoietic cell transplantation (HCT) using nonmyeloablative conditioning.

METHODS

We performed a retrospective analysis of 81 instances of relapse or progression occurring among 224 patients given HCT as treatment of their hematologic malignancies. All patients received conditioning with 2 Gy total-body irradiation with or without fludarabine and with postgrafting immunosuppression with mycophenolate mofetil and cyclosporine.

RESULTS

Overall survival of patients after relapse or progression was 36%. Fifteen of the 81 patients were given no interventions. Three of these 15 (20%) patients are alive with disease while 12 died with disease progression. Sixty-six patients (81%) received interventions, including withdrawal of immunosuppression (n=32), donor lymphocyte infusions (n=13), or chemotherapy (n=21). Twenty of the 66 (30%) are alive, 5 in complete remission, 4 in partial remission, 1 with stable and 10 with progressive disease. The overall response rate to intervention was 27%. Forty-six (70%) of the patients given interventions died, mainly due to relapse/progression. Patients not receiving interventions had a 1-year survival estimate of 15% compared to 41% in patients given interventions. Factors associated with survival in patients given intervention were disease response (p=0.002), disease category (p=0.001), and time to relapse from transplantation (p=0.0005).

CONCLUSIONS

While the overall prognosis of patients relapsing or progressing after nonmyeloablative HCT is poor, interventions such as the combined use of immunotherapy and chemotherapy can improve patient survival.

Low T-cell chimerism is not followed by graft rejection after nonmyeloablative stem cell transplantation (NMSCT) with CD34-selected PBSC

We investigate the feasibility of CD34-selected peripheral blood stem cell (PBSC) transplantation followed by pre-emptive CD8-depleted donor lymphocyte infusions (DLI) after a minimal conditioning regimen. Six patients with advanced hematological malignancies ineligible for a conventional myeloablative transplant (n=5) or metastatic renal cell carcinoma (n=1), and with an HLA-identical (n=4) or alternative (n=2) donor were included. The nonmyeloablative conditioning regimen consisted in 2 Gy TBI alone (n=4), 2 Gy TBI and fludarabine (RCC patient, n=1) or cyclophosphamide and fludarabine (patient who had previously received 12 Gy TBI, n=1). Post transplant immunosuppression was carried out with cyclosporin (CyA) and mycophenolate mofetil (MMF). Initial engraftment was achieved in all patients. One out of six patients (17%) experienced grade > or =2 acute GVHD only after abrupt cyclosporin discontinuation and alpha interferon therapy for life-threatening tumor progression. T-cell chimerism was 23% (19-30) on day 28, 32% (10-35) on day 100, 78% (49-95) on day 180 and 99.5% (99-100) on day 365. Three out of four patients who had measurable disease before the transplant experienced a complete response. We conclude that CD34-selected NMSCT followed by CD8-depleted DLI is feasible and preserves engraftment and apparently also the graft-versus-leukemia (GVL) effect. Further studies are needed to confirm this encouraging preliminary report.

Intensive care unit outcomes in elderly cancer patients

As the number of elderly patients receiving oncologic therapies increases, the need for better outcome predictors for the critically ill elderly with cancer increases. Physicians should not view age as an indicator of poor ICU outcome, as many elderly patients with cancer will derive the same benefit from intensive care as their younger counterparts. Such a gain can be accomplished without overuse of valuable resources. Similar prognostic factors that are applied to the younger cancer patients should also be applied to the elderly. These parameters, in addition to clinical judgment, can be helpful in deciding who will benefit from ICU care regardless of age. Oncologists and critical care physicians will need to collaborate and change the paradigm of ICU care for the elderly.

Allogeneic peripheral blood stem cell transplantation for high-risk non-Hodgkin's lymphoma

A high incidence of nonrelapse mortality (NRM) has limited the use of allogeneic transplantation for poor prognosis non-Hodgkin's lymphoma (NHL). We sought to improve the outcome of allografting by utilizing Filgrastim-mobilized peripheral blood stem cells (PBSC) in combination with either standard ablative or reduced-intensity conditioning. A total of 21 patients with intermediate/high-grade lymphoma and seven patients with low-grade histology were enrolled on protocols using PBSC. All patients were considered high risk for recurrence and/or NRM because of age >50 (n=16), refractory disease (n=17), failed autologous transplant (n=11) and abnormal organ function (n=2). In all, 17 patients received ablative regimens and 11 received modified conditioning including fludarabine, intravenous busulfan and ATG. Tacrolimus and mini-dose methotrexate were used for graft-versus-host-disease (GVHD) prophylaxis. Median follow-up was 38 months. Disease-free and overall survival were 57 and 58%. Seven of the 11 patients who relapsed after a previous transplant remain disease free. Four of the 10 patients with recurrent/persistent disease post transplant responded to additional therapy including withdrawal of immunosuppression+/-DLI. These results support a potent graft-versus-lymphoma effect and suggest that patients who relapse after an autologous transplant can be salvaged with an allogeneic transplant.

Minimal GVHD following in-vitro Tcell–depleted allogeneic stem cell transplantation with reduced-intensity conditioning allowing subsequent infusions of donor lymphocytes in patients with hematological malignancies and solid tumors

OBJECTIVE

Allogeneic stem cell transplantation (alloSCT) following reduced-intensity conditioning offers a relatively nontoxic regimen while preserving rapid and sustained engraftment. Acute and chronic graft-vs-host disease (GVHD) is, however, a significant cause of severe morbidity. To reduce the incidence of GVHD, we treated a group of high-risk patients with a reduced-intensity conditioning regimen followed by in vitro T-cell-depleted alloSCT using Campath 1-H incubation.

PATIENTS AND METHODS

Eighteen patients were treated with fludarabine (6 x 30 mg/m(2)), busulphan (2 x 3.2 mg/kg), and ATG (4 x 10 mg/kg) followed by the infusion of high-dose T-cell-depleted peripheral stem cells from sibling donors. No posttransplant GVHD prophylaxis was administered. At 6 months after alloSCT, low-dose donor lymphocyte infusion (DLI) was administered.

RESULTS

All patients had sustained engraftment of donor cells with a median of 95% donor cells at 3 months after alloSCT. Minimal acute and no chronic GVHD was observed after alloSCT. A high incidence of cytomegalovirus (CMV) reactivation but no CMV disease was observed. Eleven patients received DLI at a median of 6.5 months after alloSCT. Acute GVHD grade II-III developed in 6 patients. All patients showed improvement of donor chimerism after DLI. With a median follow-up of 211 days, 11 patients are alive. Particular in patients with chronic lymphocytic leukemia and acute myeloid leukemia, a significant graft-vs-tumor effect was observed.

CONCLUSIONS

In vitro T-cell-depleted alloSCT following reduced-intensity conditioning leads to durable donor engraftment without GVHD. The high levels of donor chimerism allow the subsequent use of cellular immunotherapy to treat residual disease.

Lineage-specific chimaerism after stem cell transplantation in children following reduced intensity conditioning: potential predictive value of NK cell chimaerism for late graft rejection

Chimaerism of FACS-sorted leucocyte subsets (CD14+, CD15+, CD3-/56+, CD3+/4+, CD3+/8+, CD19+) was monitored prospectively between days +14 and +100 in 39 children undergoing allogeneic stem cell transplantation with reduced intensity-conditioning regimens. Cell subsets exceeding 1% of nucleated cells were subject to cell sorting. Chimaerism was analysed by dual-colour FISH and/or by short tandem repeat-polymerase chain reaction. The chimaerism pattern on day +28 was evaluated with regard to its correlation with graft rejection. Of 39 patients, nine patients had donor chimaerism (DC) in all subsets. Mixed/recipient chimaerism (MC/RC) was detectable within T cells in 62%, within NK cells in 39% and within monocytes and granulocytes in 38% of the patients. The correlation of secondary graft rejection with the chimaerism pattern on day +28 revealed the strongest association between RC in NK-cells (P<0.0001), followed by T cells (P=0.001), and granulocytes and monocytes (P=0.034). Notably, patients with RC in T cells rejected their graft only if MC or RC was also present in the NK-cell subset. By contrast, none of the children with DC in NK cells experienced a graft rejection. These observations suggest that, in the presence of recipient T-cell chimaerism, the chimaerism status in NK-cells on day +28 might be able to identify patients at high risk for late graft rejection.