Fludarabine vs cladribine plus busulfan and low-dose TBI as reduced intensity conditioning for allogeneic hematopoietic stem cell transplantation: a prospective randomized trial

Purine analogs are often used for conditioning preceding allogeneic hematopoietic stem cell transplantation (HCT). We prospectively tested fludarabine (Flu) 40 mg/m(2)/day x 5 days vs cladribine (Clad) 10 mg/m(2)/day x 5 days plus oral busulfan (1 mg/kg q6 h x 2 days) and total body irradiation 200 cGy in 32 recipients of matched sibling and unrelated donor (URD) HCT. Patients were similar in age (median 52 years), diagnosis, extensive pre-HCT therapy (56 vs 63%), and high-risk disease status (81 vs 93%). Neutrophil engraftment was prompt (median 11 vs 12 days), but early graft failure using Clad halted randomization. Platelet recovery was prompt (median Flu 18 vs Clad 24 days). Graft-versus-host disease (GVHD) after Flu vs Clad was similar; (acute grade II/IV 56 vs 69%, P=0.26; chronic 50 vs 31%, P=0.27). Nonrelapse mortality (Flu 25 vs Clad 38%, P=0.47) and progression-free survival at 3 years were similar as well. Multivariate analyses showed slightly, but not significantly lower relative risk (RR) of neutrophil engraftment with Clad (RR 0.6 (95% CI 0.2-1.3) P=0.16) and with URD RR 0.4 (0.2-1.0) P=0.04). Older patients with advanced hematologic malignancies achieve satisfactory outcomes using either of these reduced intensity conditioning regimens.

Marked increased risk of Epstein-Barr virus-related complications with the addition of antithymocyte globulin to a nonmyeloablative conditioning prior to unrelated umbilical cord blood transplantation

Umbilical cord blood (UCB) is increasingly used as an alternative source of hematopoietic stem cells for transplantation for patients who lack a suitable sibling donor. Despite concerns about a possible increased risk of Epstein-Barr virus (EBV) posttransplantation lymphoproliferative disorder (PTLD) after UCB transplantation, early reports documented rates of PTLD comparable to those reported after HLA-matched unrelated marrow myeloablative (MA) transplantations. To further investigate the incidence of EBV PTLD after UCB transplantation and potential risk factors, we evaluated the incidence of EBV-related complications in 335 patients undergoing UCB transplantation with an MA or nonmyeloablative (NMA) preparative regimen. The incidence of EBV-related complications was a 4.5% overall, 3.3% for MA transplantations, and 7% for NMA transplantations. However, the incidence of EBV-related complications was significantly higher in a subset of patients treated with an NMA preparative regimen that included antithymocyte globulin (ATG) versus those that did not (21% vs 2%; P < .01). Nine of 11 patients who developed EBV PTLD were treated with rituximab (anti-CD20 antibody), with the 5 responders being alive and disease free at a median of 26 months. Use of ATG in recipients of an NMA preparative regimen warrants close monitoring for evidence of EBV reactivation and potentially preemptive therapy with rituximab.

Cerebral X-linked adrenoleukodystrophy: the international hematopoietic cell transplantation experience from 1982 to 1999

Cerebral X-linked adrenoleukodystrophy (X-ALD) is a disorder of very-long-chain fatty acid metabolism, adrenal insufficiency, and cerebral demyelination. Death occurs within 2 to 5 years of clinical onset without hematopoietic cell transplantation (HCT). One hundred twenty-six boys with X-ALD received HCT from 1982 to 1999. Survival, engraftment, and acute graft-versus-host disease were studied. Degree of disability associated with neurologic and neuropsychological function and cerebral demyelination were evaluated before and after HCT. Complete data were available and analyzed for 94 boys with cerebral X-ALD. The estimated 5- and 8-year survival was 56%. The leading cause of death was disease progression. Donor-derived engraftment occurred in 86% of patients. Demyelination involved parietal-occipital lobes in 90%, leading to visual and auditory processing deficits in many boys. Overall 5-year survival of 92% in patients with 0 or 1 neurologic deficits and magnetic resonance imaging (MRI) severity score less than 9 before HCT was superior to survival for all others (45%; P <.01). Baseline neurologic and neuropsychological function, degree of disability, and neuroradiologic status predicted outcomes following HCT. In this first comprehensive report of the international HCT experience for X-ALD, we conclude that boys with early-stage disease benefit from HCT, whereas boys with advanced disease may be candidates for experimental therapies.

Progenitor content of autologous grafts: mobilized bone marrow vs mobilized blood

The progenitor content of autologous peripheral blood progenitor and stem cell collections is a major determinant of prompt hematopoietic recovery following autologous stem cell transplantation. We analyzed unstimulated bone marrow (BM) and peripheral blood (PB) apheresis products in comparison to those collected following G-CSF or GM-CSF stimulation. We quantitated their committed (CFU-GM) and primitive (long-term culture-initiating cells, LTC-IC) progenitors in relation to hematologic recovery in 63 patients undergoing autografting for lymphoid malignancies. G-CSF, but not GM-CSF, substantially enriched the committed progenitor content (2.5-3.6-fold) of both PB and BM grafts. G-CSF also enriched the LTC-IC content of BM and PB compared to control grafts. GM-CSF augmented (11.5-fold) the LTC-IC content of stimulated BM, but not GM-CSF-mobilized PB. Neutrophil recovery was substantially quicker in recipients of BM or PB mobilized with G-CSF or GM-CSF. In contrast, red cell and platelet recovery was accelerated in recipients of GM-CSF-stimulated BM (but not PB) and G-CSF-stimulated PB (but not BM). No direct correlation between progenitor dose and hematopoietic recovery for neutrophils, platelets or red cells was observed. Cytokine stimulation can augment the committed and more primitive multilineage progenitor content of BM and PB grafts, to a differing extent. The uncertain relationship with multilineage myeloid recovery emphasizes the limitations in using clonogenic progenitor analyses to assess the adequacy of an autologous graft prior to transplantation.

A comparison of related donor peripheral blood and bone marrow transplants: importance of late-onset chronic graft-versus-host disease and infections

Peripheral blood hematopoietic stem cell (PBSC) transplants have been shown to result in more rapid engraftment than standard bone marrow transplants (BMTs). Little comparative data exist regarding complications in patients receiving transplants using these stem cell sources. In our study, 97 adults with advanced hematologic malignancies who received allogeneic PBSC transplants were compared with 97 adults who received allogeneic BMTs using identical preparative regimens and support parameters. The incidence of systemic infections and other major complications occurring within the first year after transplantation were calculated in both groups. Proportional hazard analysis was used to examine risk factors for death and complications in both groups. Patients receiving PBSC transplants had more rapid neutrophil (17 days versus 24 days; P <.001) and platelet engraftment (28 days versus 47 days; P <.001) than BMT recipients. The survival rate at 2 years was 38% in PBSC transplant recipients and 28% in marrow recipients (P =.08). There was no difference in rates of grade II to IV acute graft-versus-host disease (GVHD) between groups (PBSC 46%, BMT 51%; P =.3). PBSC transplant recipients were more likely to develop chronic GVHD after 180 days (hazard ratio 2.2; P =.05). Accompanying this "late-onset chronic GVHD," a pattern of more frequent late systemic fungal and cytomegalovirus infections was observed in PBSC transplant recipients. In conclusion, although PBSC transplant recipients engraft more quickly than BMT recipients and have somewhat better 2-year survival rates, they develop more frequent late-onset chronic GVHD and may have more late fungal and cytomegalovirus infections than marrow recipients. Further studies must examine this late-onset chronic GVHD and better characterize immune reconstitution in PBSC transplant recipients to understand their effects on patient recovery.

Evaluation of KIR ligand incompatibility in mismatched unrelated donor hematopoietic transplants. Killer immunoglobulin-like receptor

One of the functions of HLA class I alleles is interaction with natural killer (NK) cells. Receptors termed killer immunoglobulin-like receptors (KIRs) on NK cells recognize groups of HLA class I alleles, and interaction between receptor and class I allele inhibits reactivity of the NK cell. Failure to recognize the appropriate KIR ligand on a mismatched cell can trigger NK cell elimination of that target cell. Recent analysis of haploidentical hematopoietic transplantations has shown a reduction of graft failure, graft-versus-host disease, and relapse in those with KIR ligand incompatibility in the graft-versus-host direction. In this study we analyzed the effect of KIR ligand incompatibility on outcomes of unrelated donor bone marrow transplantations. The data show no advantage for KIR ligand incompatibility in this clinical setting as assessed by HLA-Bw4 and HLA-C alleles. It is possible that there will be a benefit of NK cell alloreactivity if strategies of haploidentical transplantation are used: high stem cell doses, extensive T-cell depletion, and no postgrafting immune suppression.

Low incidence of Epstein-Barr virus-associated posttransplantation lymphoproliferative disorders in 272 unrelated-donor umbilical cord blood transplant recipients

Umbilical cord blood (UCB) is being increasingly used for transplantation, but the ability of neonatal T cells to regulate Epstein-Barr virus (EBV)-associated lymphoproliferation is unknown. Because UCB transplantation (UCBT) is associated with a relatively low infused dose of donor T cells, frequent donor-recipient HLA disparity, and use of antithymocyte globulin during conditioning, we hypothesized that the risk of EBV-associated posttransplantation lymphoproliferative disorders (EVB-PTLD) after UCBT may be increased. To investigate the incidence of EBV-PTLD after UCBT, we analyzed 272 unrelated-donor UCBTs performed from August 1993 to December 1999 at Duke University Medical Center and the University of Minnesota. Five cases of EBV-PTLD were identified, with a cumulative incidence of 2% (95% confidence interval, 0.3%-3.7%) at 2 years. EBV-PTLD affected UCB recipients aged 1 to 49 years (median, 8 years), with 4 patients undergoing transplantation for leukemia and 1 for immunodeficiency. Patients received UCB grafts that were HLA matched (n = 1) or mismatched at 1 (n = 1) or 2 (n = 3) HLA loci. Diagnoses occurred at 4 to 14 months (median, 6 months) after UCBT, with 4 of 5 patients having preceding grade II to IV acute graft-versus-host disease and 1 being diagnosed at autopsy. Treatment of 4 patients consisted of withdrawal of immunosuppressive treatment and administration of rituximab, with 2 of 4 patients responding. Thus, the incidence of EBV-PTLD after unrelated-donor UCBT appears similar to that observed after transplantation using unrelated bone marrow (BM) and compares favorably with unrelated-donor T-cell-depleted BM transplantation. Because adoptive immunotherapy with donor lymphocytes is not an available option for recipients of unrelated-donor UCBT, new therapeutic strategies are needed, and rituximab appears promising.

Survival after transplantation of unrelated donor umbilical cord blood is comparable to that of human leukocyte antigen-matched unrelated donor bone marrow: results of a matched-pair analysis

Umbilical cord blood (UCB) is being increasingly used for hematopoietic stem cell transplantation and has been associated with a reduced incidence of severe graft-versus-host disease (GVHD). To further investigate the relative merits of unrelated donor UCB versus bone marrow (BM), a matched-pair analysis comparing the outcomes of recipients of 0 to 3 human leukocyte antigen (HLA)-mismatched UCB and HLA-A, B, DRB1-matched BM was performed. UCB patients, who received cyclosporine (CSA) and methylprednisolone (MP), were matched for age, diagnosis, and disease stage with BM patients, who received either methotrexate (MTX) and CSA (26 pairs) or T-cell depletion (TCD) and CSA/MP (31 pairs). Patients were predominantly children (median age, 5 years) undergoing transplantation for malignancy, storage diseases, BM failure, and immunodeficiency syndromes between 1991 and 1999. Although neutrophil recovery was significantly slower after UCB transplantation, the probability of donor-derived engraftment at day 45 was 88% in UCB versus 96% in BM-MTX recipients (P =.41) and 85% in UCB versus 90% in BM-TCD recipients (P =.32), respectively. Platelet recovery was similar in UCB versus BM pairs. Furthermore, incidences of acute and chronic GVHD were similar in UCB and BM recipients, with 53% of UCB versus 41% of BM-MTX recipients alive (P =.40) and 52% of UCB versus 56% of BM-TCD recipients alive at 2 years (P >.80), respectively. These data suggest that despite increased HLA disparity, probabilities of engraftment, GVHD, and survival after UCB transplantation are comparable to those observed after HLA-matched BM transplantation. Therefore, UCB should be considered an acceptable alternative to HLA-matched BM for pediatric patients.

Late outcomes after bone marrow transplant for aplastic anaemia

Allogeneic transplantation is effective in reconstituting haemopoiesis in severe aplastic anaemia (SAA). We report long-term health-related outcomes in 37 children and young adults with SAA transplanted between 1975 and 1996. The median length of follow-up was 17 years (range, 4-25 years). Using a case-control design, late social and medical outcomes in transplant recipients were compared with 146 control subjects matched for gender and age. The majority of patients received an irradiation-containing preparative regimen. There were no significant differences in the self-rating of health status between transplant recipients and controls (P = 0.8), with 71% reporting their health status as excellent and 29% as good compared with 74% and 26% of controls. They demonstrate the same normal psychosexual function as their peers and have similar educational achievements and employment history. Transplant recipients and controls are equally likely to have held a job or be currently employed and there are no significant differences in their personal income (OR = 0.60, 95% CI = 0.11-3.37). Although transplant recipients have had problems related to health insurance policies, the majority have adequate health insurance coverage. There were no differences in chronic health problems between transplant recipients and control subjects, except for expected increases in cataracts, short stature in men, hypothyroidism and gonadal dysfunction. Using self-assessment, these transplant recipients indicated an excellent level of satisfaction and social integration, showing transplantation to be an effective long-term therapy for SAA.

Impact of birthweight on healthcare charges within a managed care organization

OBJECTIVE

To determine the rate of low-birthweight (LBW) births and the association of LBW with utilization and healthcare charges in a managed care organization.

DESIGN

Observational study of computerized and medical record data.

PATIENTS AND METHODS

We assessed the rate of LBW (weight < 2500 g) for singleton infants born during 1993 and 1995 at 2 hospitals (1993, N = 3212; 1995, N = 3073). For a subset of infants born during 1995 (n = 1273), we examined differences in utilization and medical charges, by birthweight category (moderately LBW [MLBW; 1500 to 2499 g] vs normal birthweight [NBW]), at 1 year postdischarge.

RESULTS

In both 1993 and 1995, 3% of singleton infants were LBW infants, and 2% to 3% were macrosomic (> or = 4500 g). Complete data for analyses of utilization and healthcare charges were available on 1273 infants who were enrolled for the entire postdischarge year. The use of outpatient, emergency department (ED), and subspecialty care by MLBW infants and by NBW infants was similar. However, MLBW was associated with an increased rate of rehospitalization during the first year of birth (P < .01). MLBW infants' medical care charges were 46% higher than those of NBW infants (P = .0125).

CONCLUSIONS

MLBW infants and NBW infants had similar outpatient and ED service use during the first year after hospital discharge. Excess charges incurred by MLBW infants were primarily due to higher rates of rehospitalization. Of the 38 admissions, 21 were related to infection or fear of infection, and 4 were due to congenital malformations.

Response to thalidomide therapy in refractory chronic graft-versus-host disease

Chronic graft-versus-host disease (GVHD) refractory to standard immunosuppressive therapy remains a major cause of morbidity and mortality after allogeneic bone marrow transplantation (BMT). Thalidomide may be effective in some patients with high-risk or refractory chronic GVHD. We report a single-institution study of thalidomide in 37 BMT patients with extensive chronic GVHD refractory to standard immunosuppressive therapy. Acute GVHD occurred in 34 (91%) of patients and evolved progressively into chronic GVHD in 23 (62%) patients. Thalidomide was added to standard immunosuppressive therapy a median of 11 months (range 0-105 months) after the diagnosis of chronic GVHD. Fourteen of 37 (38%) patients responded after introduction of thalidomide (one complete, 13 partial). Ten of 21 (46%) children and four of 16 (25%) adults responded. Responses were seen in eight of 17 (47%) recipients of related donor marrow and six of 20 (30%) recipients of unrelated donor marrow. Eight of 23 (34%) patients with progressive onset of chronic GVHD showed a response. There were no deaths among the responders. The remaining 23 patients (62%) did not respond and of these only two survive, one with progressive scleroderma, and the other with bronchiolitis obliterans. Chronic GVHD with associated infection (most commonly disseminated fungal infection) was a major contributor to mortality in all cases. Overall, after initiation of thalidomide, the 2-year Kaplan-Meier survival was 41% (95% C.I. 24%-59%). We conclude that thalidomide is a useful and well-tolerated therapy for patients with previously treated refractory chronic GVHD, including those with progressive onset of chronic GVHD, recipients of unrelated donor marrow, and children. Earlier introduction of thalidomide as an adjunct to standard immunosuppressive therapy may lead to more frequent responses and possible better survival.

Busulfan pharmacokinetics do not predict relapse in acute myeloid leukemia

The purpose of this study was to evaluate the influence of busulfan (BU) pharmacokinetics on survival, grades II-IV acute graft-versus-host disease (GVHD), non-relapse mortality (NRM) and relapse in a group composed of 45 children (<18 years) and seven adults with acute myeloid leukemia (AML) in first complete remission and undergoing hematopoietic stem cell transplantation (SCT). Fifty-two patients underwent autologous (n = 25) or allogeneic (n = 27) SCT. The median age was 8.9 years (range 0.6-53 years). Conditioning therapy consisted of BU and cyclophosphamide. Improved disease-free survival was found in those patients with a steady-state concentration of BU (CssBU) below the median (<578 mg/ml, P = 0.05), and the same trend was noted for overall survival (P = 0.07). This was secondary to a higher incidence of NRM in the group of patients with CssBU above the median (P = 0.06). There was no significant correlation with CssBU and relapse (P = 0.31). No association between CssBU and GVHD was found in allogeneic patients (P = 0.30). Relapse was evaluated among the subgroups of age (< or >10 years) and transplant type (allogeneic or autologous) with no statistically significant association observed among these factors. Multiple regression analysis for relapse revealed no significant correlation with CssBU above or below the median, age, or transplant type. In this study, CssBU below the median did not correlate with an inferior outcome for patients with AML. Pharmacokinetic dosing of BU may be important for prevention of NRM but does not appear to influence the risk of relapse in this largely pediatric population with AML.

Increasing incidence of diffuse alveolar hemorrhage following allogeneic bone marrow transplantation: cryptic etiology and uncertain therapy

Diffuse alveolar hemorrhage (DAH) is a non-infectious pulmonary complication of bone marrow transplantation (BMT) with resultant high mortality. It reportedly occurs primarily in autologous recipients. We examined the incidence of DAH in our center in order to assess potential risk factors and develop preventive strategies. Between 1991 and 1997, 23 cases of DAH occurred in 922 adult patients (2.5%) receiving BMT for hematological malignancy. Strikingly, 12 cases occurred in 1997 with the majority in recipients of allogeneic matched sibling donor stem cells. Treatment with high-dose steroids, 250 mg to 2 g/day, in 15 patients led to transient improvement in 10 patients, but 21 of the 23 patients required mechanical ventilation. Mortality was high with 17 patients (74%) dying a median of 39 days (range 22-47) post transplant; a median of 17 days post onset of DAH (range 5-34). Six patients are alive with a median follow-up of 18 months (range 12-60). No recognizable alteration in supportive care, conditioning regimen, GVHD prophylaxis or cytokine usage was associated with this striking increase in the frequency of DAH after allografting. Further follow-up is required to establish whether this increase in the incidence of DAH in allogeneic transplantation is an isolated occurrence or an ongoing problem. If indeed there is a real increase in the incidence of this complication, then efforts need to be directed towards elucidating a possible cause or risk factors. We offer the possibility that a new unidentified infection, undetected by current microbiological tests might contribute to this striking increase in DAH. These data, while not establishing a cause, suggest a markedly augmented risk of DAH in allogeneic BMT. In addition, high-dose corticosteroids have only limited efficacy as therapy for DAH after allotransplantation. Further investigation into the pathogenesis of this syndrome is essential as is prompt and immediate consideration of DAH in all patients with respiratory compromise early after BMT.

Thrombopoietic cytokines in relation to platelet recovery after bone marrow transplantation

In order to evaluate the importance of different thrombopoietic stimulatory cytokines in accelerating platelet recovery after bone marrow transplantation (BMT), we assayed serial plasma concentrations of three cytokines, thrombopoietin (TPO), interleukin-6 (IL-6), and IL-11 through the course of platelet nadir and recovery after BMT. Both mean TPO and IL-6 levels showed a marked rise and later fall preceding or coincident with the platelet nadir and recovery, suggesting their potential role as circulating regulators or stimulators of thrombopoiesis. In contrast, IL-11 levels remained remarkably constant through the whole course suggesting that this cytokine, though capable of stimulating thrombopoiesis, does not serve as a circulating regulator of platelet production. Additionally, we assayed the levels of these three cytokines following initial platelet transfusion to assess the capacity of transfused platelets to adsorb these thrombopoietic cytokines from the plasma and reduce their circulating levels, thus potentially modifying their availability for stimulating megakaryocyte proliferation. No consistent falls in TPO, IL-6 or IL-11 levels were observed following the initial two platelet transfusions. These data support the importance of circulating TPO and IL-6 as hormones capable of stimulating platelet production. Their physiologic relevance as in vivo regulators of thrombopoiesis and clinical utility for therapy of thrombocytopenia need further investigation.

Pulmonary cytolytic thrombi: a newly recognized complication of stem cell transplantation

Over the past 5 years we have recognized a new pulmonary complication of hematopoietic stem cell transplantation (HSCT) associated with fever and pulmonary nodules termed 'pulmonary cytolytic thrombi' (PCT). Retrospective analysis of medical and radiographic records and pathologic material from 13 HSCT recipients with PCT and a review of the Blood and Marrow Transplant Database for all patients with radiographic evidence of pulmonary nodules or who underwent open-lung biopsy from 1 January 1993 to 31 December 1998 (n = 1228) were performed. The median age of patients with PCT was 11.9 years (range, 1.3-29.7 years). All patients developed fever at a median of 72 days (range, 8-343 days) post transplant, followed by pulmonary nodules on chest CT. Eleven patients were receiving therapy for active GVHD (acute, grades I-IV (n = 10); extensive chronic (n = 1)). Biopsy of the pulmonary nodules revealed a unique pattern of necrotic, basophilic thromboemboli with amorphous material suggestive of cellular breakdown products. This was descriptively labeled 'pulmonary cytolytic thrombi'. Immunohistochemical staining revealed entrapped leukocytes and disrupted endothelium, but was negative for histiocytes. Cultures and immunohistochemical stains were negative for infectious agents. Empiric therapy included systemic corticosteroids (n = 9) and amphotericin (n = 7). Nine patients survive with resolution of PCT at a median follow-up of 1.5 years. Bone Marrow Transplantation (2000) 25, 293-300.

Autologous stem cell transplantation for high-risk pediatric solid tumors

Many solid tumors exhibit a steep dose-response to alkylating agents, and autologous stem cell transplantation (ASCT) allows escalation of the chemotherapy dose for treatment of high risk solid tumors. We have transplanted 24 children and young adults with relapsed or metastatic solid tumors on two consecutive ASCT protocols consisting primarily (protocol MT 8911) or exclusively (MT 9408) of alkylating agents. The median time to neutrophil engraftment was 21 days in protocol MT 8911 (no prophylactic use of growth factors) and 14 days in MT 9408 (G-CSF, 5 microg/kg, started on day 0). Disease-free survival estimated by the Kaplan-Meier method is 39% (95% CI: 19-59%) at 2 years after transplant and 34% (95% CI: 14-54%) at 4 years after transplant. Six of the nine patients with metastatic or relapsed disease that were transplanted while in complete remission (four patients with Ewing's sarcoma family of tumors and two patients with anaplastic Wilms tumor) are alive and disease-free with a median follow-up of 37 months (range 20-74 months). The estimated 4 year survival for patients receiving a transplant while in high risk remission was 78% (95% CI: 51-100%). In contrast, 13/15 patients that were transplanted while in partial remission died because of progressive disease or transplant-related complications. There were three transplant-related deaths (12.5%), including one patient with multiorgan failure, and two patients with complications of hepatic veno-occlusive disease. Our data indicate that autologous stem cell transplantation should be considered for consolidation therapy of high risk and relapsed pediatric patients with solid tumors who have achieved complete remission.

High spontaneous IL-10 production in unrelated bone marrow transplant recipients is associated with fewer transplant-related complications and early deaths

Interleukin 10 (IL-10) is a potent inhibitor of proliferative T cell responses toward alloantigens, and suppresses the production of pro-inflammatory cytokines which are important in cellular activation and recruitment to sites of inflammation. Because of these properties, we hypothesized that high IL-10 production in patients prior to BMT may predict a better outcome. To investigate this, peripheral blood mononuclear cells (PBMNC) were obtained from 58 recipients (11 autologous, 25 related donor (RD), and 22 unrelated donor (URD)), prior to conditioning therapy. PBMNC were cultured for 24 h in the presence and absence of lipopolysaccharide (LPS) and culture supernatants were assayed for IL-10 using an ELISA method. Spontaneously produced and LPS-stimulated IL-10 levels were correlated with the development of transplant-related complications (TRC) including grade II-IV acute GVHD, veno-occlusive disease, idiopathic pneumonia syndrome and multi-organ dysfunction syndrome, and with death before day 100. For the autologous group, there were no TRC and only one death prior to day 100; therefore, no statistical comparisons to IL-10 levels could be made. In the RD group, 36% developed one or more TRC and 24% died before day 100; however, there were no statistically significant associations between spontaneous or LPS-induced IL-10 levels. In URD patients 41% developed TRC and 55% died prior to day 100. In this group, higher levels of spontaneous IL-10 production were associated with a lower overall occurrence of TRC (P = 0.03) and early death (P = 0.04). Our data would indicate that higher levels of IL-10 production prior to URD BMT may predict fewer TRC, as well as early deaths. The hypothesis that high IL-10 production prior to BMT may decrease complications following URD BMT warrants further testing.

B cell lymphoproliferative disorders following hematopoietic stem cell transplantation: risk factors, treatment and outcome

Twenty-six cases of B cell lymphoproliferative disorder (BLPD) were identified among 2395 patients following hematopoietic stem cell transplants (HSCT) for which an overall incidence of BLPD was 1.2%. The true incidence was probably higher, since 9/26 of the diagnoses were made at autopsy. No BLPD was observed following autologous HSCT, so risk factor analyses were confined to the 1542 allogeneic HSCT. Factors assessed were HLA-mismatching (> or = 1 antigen), T cell depletion (TCD), presence of acute GvHD (grades II-IV), donor type (related vs unrelated), age of recipient and donor, and underlying disease. Factors found to be statistically significant included patients transplanted for immune deficiency and CML, donor age > or = 18 years, TCD, and HLA-mismatching, with recipients of combined TCD and HLA-mismatched grafts having the highest incidence. Factors found to be statistically significant in a multiple regression analysis were TCD, donor age and immune deficiency, although 7/8 of the patients with immunodeficiencies and BLPD received a TCD graft from a haploidentical parent. The overall mortality was 92% (24/26). One patient had a spontaneous remission, but subsequently died >1 year later of chronic GVHD. Thirteen patients received therapy for BLPD. Three patients received lymphocyte infusions without response. The only patients with responses and longterm survival received alpha interferon (alphaIFN). Of seven patients treated with alphaIFN there were four responses (one partial and three complete). These data demonstrate that alphaIFN can be an effective agent against BLPD following HSCT, if a timely diagnosis is made.

Comparative analysis of autografting in chronic myelogenous leukemia: effects of priming regimen and marrow or blood origin of stem cells

The aims of this study were (1) to evaluate the effect of intermediate (cyclophosphamide alone) or intensive (mitoxantrone, cytosine arabinoside, cyclophosphamide) priming on the cytogenetic response in mobilized bone marrow (BM) or peripheral blood (PB) progenitors in patients with chronic myelogenous leukemia (CML), (2) to determine the incidence of cytogenetic remissions after mobilized progenitor transplantation in CML, and (3) to determine the effect of in vivo priming on the ability to select Philadelphia chromosome-negative (Ph-negative) CD34(+)HLA-DR- cells from mobilized BM or PB in quantities sufficient for transplantation. Between February 1994 and March 1997, 44 patients were enrolled in three sequential protocols. Although the duration of neutropenia after only cyclophosphamide mobilization was shorter, clinical morbidity for the intermediate and intensive priming protocols was similar. Cytogenetic responses in mobilized PB progenitors were similar after mobilization with either intermediate or intensive chemotherapy. The degree of Ph negativity in the mobilized product correlated with disease stage at the time of mobilization (early chronic phase [ECP] > late CP > accelerated phase). Cytogenetic responses after transplantation with mobilized progenitors obtained after the different regimens were similar. The cytogenetic status of the graft predicted the cytogenetic status of marrow obtained 3 weeks after transplantation whereas cytogenetic responses 3, 6, and 12 months after transplantation correlated with the number of BCR/ABL-negative CD34(+)HLA-DR- cells, but not the number of Ph-negative metaphases in the graft. In patients with ECP CML, mobilized PB collections yielded significantly more CD34(+)HLA-DR- cells than from steady state or mobilized BM. CD34(+)HLA-DR- cells were Ph negative and polyclonal (X-chromosome inactivation) in the majority of ECP CML patients, before and after mobilization and irrespective of the mobilization regimen. Because infusion of large numbers of Ph-negative CD34(+)HLA-DR- cells predicted superior outcome after transplantation, approaches in which CD34(+)HLA-DR- cells are selected from mobilized PB may result in longer lasting and clinically significant cytogenetic responses after transplantation.