Evaluation of allogeneic transplantation in first or later minimal residual disease - negative remission following adult-inspired therapy for acute lymphoblastic leukemia.

Comparisons without hematopoietic cell transplantation (HCT) to myeloablative (MAC) or reduced-intensity HCT (RIC) for adults with acute lymphoblastic leukemia (ALL) in first minimal-residual-disease negative remission (MRD(Neg) CR1) are limited. Further, the importance of MRD(Neg) following salvage therapy (MRD(Neg) CR2+) is unknown. We evaluated 89 patients in MRD(Neg) CR1 after adult-inspired treatment: 33 received MAC (12 Philadelphia chromosome [Ph]+), 17 received RIC (13 Ph+), and 39 Deferred HCT (3 Ph+). Three-year overall survival (OS) estimates for MAC, RIC, and Deferred HCT were 71%, 69%, and 68%, while 3-year event-free survival (EFS) estimates were 65%, 54%, and 28%, respectively. Further, HCT in MRD(Neg) CR1 performed similarly to MRD(Neg) CR2+: 3-year OS estimates were 70% and 69%, and 3-year EFS estimates were 62% and 62%, respectively. In conclusion, adults with ALL in MRD(Neg) CR1 following adult-inspired therapy had similar OS with or without HCT, and HCT in MRD(Neg) CR2 + can yield long-term survival.

Hematopoietic Cell Transplantation after Solid Organ Transplantation.

Solid organ transplantation (SOT) followed by hematopoietic cell transplantation (HCT) has been used to treat a single disease with multiorgan involvement or 2 separate diseases, the first requiring SOT and the second often a possible complication of SOT. Results of such serial transplants have been reported sporadically in the literature, usually as single case studies. Thirteen autologous and 27 allogeneic HCTs after SOT published previously are summarized. A more detailed review is provided for an additional 16 patients transplanted at a single institution, 8 of whom had autologous and 8 of whom had allogeneic HCT after SOT. Five of 8 autologous transplant recipients are alive a median of 4.6 years after HCT. Four of 8 allogeneic HCT recipients are alive a median of 8.7 years after HCT. In carefully selected patients, HCT after SOT is feasible and associated with a low incidence of either solid organ or hematopoietic cell rejection.

Impact of minimal residual disease, detected by flow cytometry, on outcome of myeloablative hematopoietic cell transplantation for acute lymphoblastic leukemia.

In this retrospective study, we evaluated the impact of pre- and posttransplant minimal residual disease (MRD) detected by multiparametric flow cytometry (MFC) on outcome in 160 patients with ALL who underwent myeloablative allogeneic hematopoietic cell transplantation (HCT). MRD was defined as detection of abnormal B or T cells by MFC with no evidence of leukemia by morphology (<5% blasts in marrow) and no evidence of extramedullary disease. Among 153 patients who had pre-HCT flow data within 50 days before transplant, MRD pre-HCT increased the risk of relapse (hazard ratio (HR) = 3.64; 95% confidence interval (CI), 1.87-7.09; P = .0001) and mortality (HR = 2.39; 95% CI, 1.46-3.90, P = .0005). Three-year estimates of relapse were 17% and 38% and estimated 3-year OS was 68% and 40% for patients without and with MRD pre-HCT, respectively. 144 patients had at least one flow value post-HCT, and the risk of relapse among those with MRD was higher than that among those without MRD (HR = 7.47; 95% CI, 3.30-16.92, P < .0001). The risk of mortality was also increased (HR = 3.00; 95% CI, 1.44-6.28, P = .004). These data suggest that pre- or post-HCT MRD, as detected by MFC, is associated with an increased risk of relapse and death after myeloablative HCT for ALL.

Conditioning with treosulfan and fludarabine followed by allogeneic hematopoietic cell transplantation for high-risk hematologic malignancies.

In this prospective study 60 patients of median age 46 (range: 5-60 years), with acute myelogenous leukemia (AML; n = 44), acute lymphoblastic leukemia (ALL; n = 3), or myelodysplastic syndrome (MDS; n = 13) were conditioned for allogeneic hematopoietic cell transplantation with a treosulfan/fludarabine (Flu) combination. Most patients were considered at high risk for relapse or nonrelapse mortality (NRM). Patients received intravenous treosulfan, 12 g/m(2)/day (n = 5) or 14 g/m(2)/day (n = 55) on days -6 to -4, and Flu (30 mg/m(2)/day) on days -6 to -2, followed by infusion of marrow (n = 7) or peripheral blood stem cells (n = 53) from HLA-identical siblings (n = 30) or unrelated donors (n = 30). All patients engrafted. NRM was 5% at day 100, and 8% at 2 years. With a median follow-up of 22 months, the 2-year relapse-free survival (RFS) for all patients was 58% and 88% for patients without high-risk cytogenetics. The 2-year cumulative incidence of relapse was 33% (15% for patients with MDS, 34% for AML in first remission, 50% for AML or ALL beyond first remission and 63% for AML in refractory relapse). Thus, a treosulfan/Flu regimen was well tolerated and yielded encouraging survival and disease control with minimal NRM. Further trials are warranted to compare treosulfan/Flu to other widely used regimens, and to study the impact of using this regimen in more narrowly defined groups of patients.

Hematopoietic cell transplantation as curative therapy for idiopathic myelofibrosis, advanced polycythemia vera, and essential thrombocythemia.

A total of 104 patients, aged 18 to 70 years, with a diagnosis of chronic idiopathic myelofibrosis (CIMF), polycythemia vera (PV), or essential thrombocythemia (ET) with marrow fibrosis were transplanted from allogeneic (56 related and 45 unrelated) or syngeneic (n = 3) donors. Busulfan (BU) or total body irradiation (TBI)-based myeloablative conditioning regimens were used in 95 patients, and a nonmyeloablative regimen of fludarabine plus TBI was used in 9 patients. The source of stem cells was bone marrow in 43 patients and peripheral blood in 61 patients. A total of 63 patients were alive at a follow-up of 1.3-15.2 years (median, 5.3 years), for an estimated 7-year actuarial survival rate of 61%. Eleven patients had recurrent/persistent disease, of whom 8 died. Nonrelapse mortality was 34% at 5 years. Patients conditioned with targeted BU (plasma levels 800-900 ng/mL) plus cyclophosphamide (tBUCY) had a higher probability of survival (68%) than other patients. Dupriez score, platelet count, patient age, and comorbidity score were statistically significantly associated with mortality in univariate models. In a multivariable regression model, use of tBUCY (P = .03), high platelet count at transplantation (P = .01 for PV/ET; P = .39 for other diagnoses), younger patient age (P = .04), and decreased comorbidity score (P = .03) remained statistically significant for improved survival. Our findings show that hematopoietic cell transplantation offers potentially curative treatment for patients with ICMF, PV, or ET.

Reduced incidence of acute and chronic graft-versus-host disease with the addition of thymoglobulin to a targeted busulfan/cyclophosphamide regimen.

To reduce the incidence of graft-versus-host disease (GVHD), we added Thymoglobulin (THY) to dose-adjusted oral busulfan plus cyclophosphamide (targeted BUCY). The starting dose of THY was 4.5 mg/kg given over days -3, -2, and -1, escalated in steps of 1.5 mg/kg in cohorts of 15 evaluable patients. Escalation was dependent on acute GVHD incidence and Epstein-Barr virus reactivation. Fifty-six patients with myelodysplastic syndrome and other myeloid disorders underwent transplantation with peripheral blood progenitor cells from related (n=30) or unrelated (n=26) donors. All but 2 patients achieved engraftment, and 56% survived in remission beyond 1 year. The incidence of acute GVHD was 50%, and that of chronic GVHD was 34%. The highest THY dose was 6.0 mg/kg, a dose at which 1 patient experienced Epstein-Barr virus reactivation. Nine patients did not receive the prescribed THY dose. Results were comparable for related and unrelated transplants and for patients given 4.5 or 6.0 mg/kg THY. Among 27 myelodysplastic syndrome patients (14 with related and 13 with unrelated donors) who underwent transplantation concurrently with targeted BUCY without THY, the incidence of acute and chronic GVHD was 82%. Thus, THY 4.5 to 6.0 mg/kg seemed beneficial for GVHD prevention in BUCY-conditioned patients who underwent transplantation with peripheral blood progenitor cells, although relapse-free survival did not differ significantly from that in comparable historical controls not given THY.

Conditioning with targeted busulfan and cyclophosphamide for hemopoietic stem cell transplantation from related and unrelated donors in patients with myelodysplastic syndrome.

A total of 109 patients (aged 6-66 years; median, 46 years) with myelodysplastic syndrome (MDS) were treated with busulfan (BU) targeted to plasma concentrations of 800 to 900 ng/mL plus cyclophosphamide (CY), 2 x 60 mg/kg, and hemopoietic stem cell (HSC) transplantation from related (n = 45) or unrelated donors (n = 64). At the time of transplantation, 69 patients had less than 5% myeloblasts in the marrow, and 40 patients had more advanced disease. All but 2 evaluable patients had engraftment. The Kaplan-Meier estimates of 3-year relapse-free survival (RFS) were 56% for related and 59% for unrelated recipients. The cumulative incidences of relapse were 16% for related and 11% for unrelated recipients. Nonrelapse mortality (NRM) at 100 days (3 years) was 12% (28%) for related and 13% (30%) for unrelated recipients. The only factor significant for RFS was the etiology of MDS (de novo better than treatment related; P =.03). Factors significantly correlated with relapse were advanced French-American-British classification (P =.002) and International Prognostic Scoring System score (P =.009), poor-risk cytogenetics (P =.03), and treatment-related etiology (P =.03). None of the factors examined was statistically significant for NRM. Patient age and donor type had no significant impact on outcome. RFS tended to be superior in patients receiving transplants with peripheral blood rather than marrow stem cells. Thus, a targeted BUCY regimen provided effective transplant conditioning for patients with MDS receiving transplants from HLA-identical siblings or alternative donors. Although there was still considerable nonrelapse morbidity and mortality, the present regimen was used successfully even in patients older than 60 years of age.

Induction of complete remission of advanced stage mycosis fungoides by allogeneic hematopoietic stem cell transplantation.

Advanced mycosis fungoides (MF) is incurable with conventional treatments. High-dose chemoradiotherapy with autologous bone marrow transplantation has induced remissions in a small number of patients with MF, but this modality is limited by a high relapse rate. We report induction of complete remission in a 37-year-old woman with rapidly progressive stage IV MF with allogeneic stem cell transplantation (Allo SCT). She remains in continuous complete remission 2 years after transplant. Allo SCT for MF is theoretically attractive, because there is no contamination of the graft by malignant cells, and because of the possibility of graft-versus-tumor effect. Although the results in this patient are encouraging, more patients and longer follow-up are needed to define the usefulness of Allo SCT in the treatment of MF.