Brentuximab vedotin in combination with or without donor lymphocyte infusion for patients with Hodgkin lymphoma after allogeneic stem cell transplantation.

In our study, we evaluated the safety and efficacy of Brentuximab vedotin (BV) with or without the addition of donor lymphocyte infusion (DLI) after allogeneic stem cell transplantation (allo-SCT) in 16 patients with advanced Hodgkin lymphoma (HL). Thirteen patients with relapsed HL after allo-SCT received BV as treatment for active disease. Three patients without progression of HL after allo-SCT received BV as consolidation. Twelve patients had been previously exposed to BV for treatment of relapse after autologous-SCT. Ten out of 16 patients received BV in combination with DLI. Among the 13 patients treated for active disease, CR and PR was observed in 7 and 2 patients, respectively. With a median follow-up of 13 months, 13 out of 16 patients are alive, while 3 died because of disease progression. The median PFS was 6 months. DLI-associated GVHD occurred in seven patients. Five patients with GVHD required immunosuppression, and in all cases, GVHD resolved after a short course of low dose steroids, implying that an anti-GVHD modulating effect could be induced by the concurrent administration of BV. No serious adverse event was observed in any of the patients.

Fludarabine and treosulfan compared with other reduced-intensity conditioning regimens for allogeneic stem cell transplantation in patients with lymphoid malignancies.

Allogeneic stem-cell transplantation (SCT) is a potentially curative therapy for lymphoid malignancies. Myeloablative conditioning is associated with high non-relapse mortality (NRM). Reduced-intensity condition (RIC) reduces NRM but relapse rate is increased. Novel regimens with intensive anti-malignancy activity but limited toxicity are of benefit. We evaluated outcomes of 144 lymphoma patients given allogeneic SCT with RIC consisting of fludarabine and treosulfan (FT, n=50), intravenous-busulfan (FB2, n=38) or melphalan (FM, n=56). Sixty-nine patients (48%) had chemo-sensitive disease and 75 (52%) had chemo-refractory disease at SCT. The median follow-up is 39 months (4-149). Three-year survival was 67, 74 and 48% after FT, FB2 and FM, in chemo-sensitive disease (P=0.14) and 34, 11 and 17% in chemo-refractory disease, respectively (P=0.08). Three-year NRM was 24, 24 and 54% (P=0.002), whereas relapse mortality was 22, 34 and 18%, respectively (P=0.13). Multivariate analysis identified a high comorbidity-score, chemo-refractory disease and FM as associated with shortened survival. In conclusion, FB2 is associated with low NRM and good results in chemo-sensitive disease, but with higher relapse mortality rates. FM controls disease better, but with high NRM. FT probably balances these outcomes more optimally. It is as safe as FB2 and as cytoreductive as FM, resulting in improved outcome, mostly in advanced disease.

Mobilized peripheral blood grafts include more than hematopoietic stem cells: the immunological perspective.

Although stem cell mobilization has been performed for more than 20 years, little is known about the effects of mobilizing agents on apheresis composition and the impact of graft cell subsets on patients' outcome. With the increasing use of plerixafor and the inclusion of poor mobilizers in autologous transplant procedures, new parameters other than CD34(+) stem cell dose are emerging; plerixafor seems to mobilize more primitive CD34(+)/CD38(-) stem cells compared with G-CSF, but their correlation with stable hematopoietic engraftment is still obscure. Immune recovery is as crucial as hematopoietic reconstitution, and higher T and natural killer cells infused within the graft have been correlated with better outcome in autologous transplant; recent studies showed increased mobilization of immune effectors with plerixafor compared with G-CSF, but further data are needed to clarify the clinical impact of these findings. In the allogeneic setting, much evidence suggests that mobilized T-cell alloreactivity is tempered by G-CSF, probably with the mediation of dendritic cells, even though no clear correlation with GVL and GVHD has been found. Plerixafor is not approved in healthy donors yet; early data suggest it might mobilize a GVHD protective balance of immune effectors, but further studies are needed to define its role in allogeneic transplant.

Secondary malignancies after allogeneic stem-cell transplantation in the era of reduced-intensity conditioning; the incidence is not reduced.

Secondary malignancies are well established complication in long-term survivors after allogeneic stem-cell transplantation (SCT) with myeloablative conditioning (MAC). Fludarabine-based reduced-intensity (RIC) and reduced-toxicity conditioning (RTC) regimens are increasingly used in the last decade; however, due to limited long-term follow-up, there is no data on secondary malignancies in this setting. The records of 931 consecutive patients given allogeneic SCT with MAC (n=257), RIC (n=449) or RTC (n=225), in a single institution over a 13-year period, were reviewed. Twenty-seven patients had secondary malignancy, diagnosed a median of 43 months (7 months-11.5 years) after SCT. The 10-year cumulative incidence was 5.6% (95% confidence interval (CI), 3.6-8.7), twice the expected rate in matched normal population. The incidence was 1.7, 7.4 and 5.7% after MAC, RIC and RTC, respectively (P=0.02). Multivariate analysis identified fludarabine-based conditioning (hazard ratio (HR) 3.5, P=0.05), moderate-severe chronic graft-versus-host disease (HR 2.8, P=0.01) and diagnosis of chronic myeloproliferative or non-malignant disease (HR 0.2, P=0.04) as risk-factors for secondary malignancy. The related 10-year mortality rate was 2.4% (95% CI, 1.0-5.4). In conclusion, the risk of secondary malignancies is not reduced and is even possibly increased in the era of fludarabine-based RIC/RTC. Patients and physicians should be aware of this association and life-long cancer screening is required for all transplant survivors.

Allo-SCT for AML and MDS with treosulfan compared with BU-based regimens: reduced toxicity vs reduced intensity.

Allo-SCT with reduced-intensity conditioning (RIC) results in lower non-relapse mortality (NRM), but higher relapse rate than myeloablative conditioning (MAC) in AML/myelodysplastic syndromes (MDS). Novel regimens with intensive anti-leukemic activity, but with limited toxicity will be of benefit. In all, 85 patients with AML/MDS, not eligible for MAC, were given fludarabine-treosulfan conditioning (FT). Outcomes were compared with those in patients given fludarabine-BU RIC (FB2, n=106) or reduced-toxicity (RTC) conditioning (FB4, fludarabine and myeloablative BU dose, n=85). The 5-year NRM was 29%, 20% and 18% after FT, FB2 and FB4, respectively (P=NS). Multivariate analysis (MVA) identified comorbidity score (HCT-CI) >2 and advanced disease as adverse factors with no independent impact of regimen. The 5-year relapse rate was 36%, 47% and 40%, respectively (P=0.17). MVA identified advanced disease as the major adverse factor, while FT had significantly lower relapse rate (hazard ratio 0.6, P=0.03). The 5-year survival (OS) was 37% with advanced disease. HCT-CI >2 and age ≥ 50 were found as adverse factors. The 5-year OS was 46%, 44% and 50% after FT, FB2 and FB4 in early-intermediate-stage disease (P=NS) and 33%, 9% and 28% in advanced disease, respectively (P=0.02). FT is an RTC regimen with intensive anti-leukemia effect in MAC non-eligible patients.

Ibritumomab tiuxetan (Zevalin) combined with reduced-intensity conditioning and allogeneic stem-cell transplantation (SCT) in patients with chemorefractory non-Hodgkin's lymphoma.

Allogeneic SCT is an effective therapy for lymphoma. Reduced-intensity conditioning (RIC) reduces non-relapse mortality (NRM) associated with myeloablative conditioning but relapse rates are high when performed in active disease. This study was designed to explore the safety and outcome of ibritumomab tiuxetan (Zevalin) combined with RIC in patients with advanced lymphoma. The study included 12 patients, median age 54 years (37-62), with a median of four prior treatments (2-6) and active disease documented on PET-CT. Zevalin 0.4 mCi/kg was given on day -14 and fludarabine combined with BU (n=6) or melphalan (n=6) was started on day -6. GVHD prevention was tapered 3 months after SCT to augment the graft-versus-lymphoma effect. All patients engrafted, a median of 14 days after SCT. Eighty-three percent achieved CR/PR. With a median follow-up of 21 months (12-37), 2-year PFS is 33%. Only three patients relapsed; cumulative incidence 25%. NRM was 42%, predominantly due to acute GVHD. Zevalin-RIC is feasible with consistent engraftment, acceptable organ toxicity, but high rates of acute GVHD. The low incidence of relapse suggests augmented anti-lymphoma effect. Zevalin-RIC merits further study. Better results may be achieved in patients earlier in disease course and with longer duration of immune-suppression.

Comparison between two fludarabine-based reduced-intensity conditioning regimens before allogeneic hematopoietic stem-cell transplantation: fludarabine/melphalan is associated with higher incidence of acute graft-versus-host disease and non-relapse mortality and lower incidence of relapse than fludarabine/busulfan.

Reduced-intensity conditioning (RIC) regimens are increasingly used in allogeneic stem-cell transplantation (SCT). There are no data whether any of these regimens has advantage and in what setting. We retrospectively analyzed SCT outcomes in 151 patients given fludarabine-based RIC for various hematological malignancies; 72 conditioned with fludarabine and intravenous-busulfan (FB) and 79 with fludarabine and melphalan (FM). FM was more myelosuppressive. Grade III-IV organ toxicity occurred in 31 and 53% of FB and FM recipients (P=0.005) and acute graft-versus-host disease grade II-IV in 33 and 53%, respectively (P=0.01). Non-relapse mortality rate (NRM) was 16 and 40%, respectively (P=0.003). Active disease (HR 2.2, P=0.003) and prior autologous SCT (HR 1.7, P=0.04) predicted inferior overall survival (OS). Among patients transplanted in remission, OS was 72 and 36% after FB and FM, respectively (P=0.03) due to increased NRM with FM. Similarly, patients transplanted in active disease experienced higher NRM with FM, however lower relapse rates resulted in equivalent OS. In conclusion, there are marked differences in outcome between RIC regimens that are theoretically dose-equivalent. The FM regimen is more myelosuppressive and toxic but controls disease better. FB was associated with improved survival in patients transplanted in remission. These observations merit further study in prospective studies.

Allogeneic hematopoietic stem-cell transplantation in AML and MDS using myeloablative versus reduced-intensity conditioning: the role of dose intensity.

Allogeneic stem-cell transplantation (SCT) with both myeloablative and reduced-intensity conditioning (RIC) is an effective therapy in AML/MDS. However, the relative merits of each may differ in different settings. To define the role of dose intensity, we analyzed SCT outcomes of 112 consecutive patients with AML/MDS. A total of 45 patients met eligibility criteria for standard myeloablative conditioning and were given intravenous-busulfan (12.8 mg/kg) and cyclophosphamide (ivBuCy). A total of 67 noneligible patients were given RIC with fludarabine and intravenous-busulfan (6.4 mg/kg, FB2, n=41) or a modified myeloablative regimen with fludarabine and myeloablative doses of intravenous-busulfan (12.8 mg/kg, FB4, n=26). The overall survival (OS) at 2 years was 50, 49 and 47% after ivBuCy, FB4 and FB2, respectively (P=NS). Nonrelapse mortality was higher after ivBuCy, 22 vs 8% (P=0.05), but relapse rates were lower. Active disease at SCT was the most significant predictor of reduced survival in multivariable analysis (HR 4.5, P=0.0001). Myeloablative and RIC regimens had similar outcomes when leukemia was in remission at SCT; however, patients with active disease could only be salvaged by myeloablative conditioning. Among the latter, OS was 45% after ivBuCy but no FB2 recipient survived (P=0.02). Patients with active disease, ineligible for standard myeloablation, could tolerate modified myeloablation well; however, long-term outcome cannot be determined yet.

Hematopoietic stem-cell transplantation from unrelated donors in elderly patients (age >55 years) with hematologic malignancies: older age is no longer a contraindication when using reduced intensity conditioning.

Allogeneic stem cell transplantation (SCT) is a potentially curative approach for patients with hematological malignancies. Reduced-intensity conditioning regimens allow SCT in elderly patients; however, there are only limited data on the feasibility and outcomes of unrelated donor SCT in these patients. In this study, we analyzed, retrospectively, data of 36 patients with various hematological malignancies and median age 58 years (range, 55-66), who were given unrelated donor SCT after reduced-intensity conditioning. The preparative regimen consisted of fludarabine combined with oral busulfan (8 mg/kg, n=8), intravenous busulfan (6.4 mg/kg, n=11), treosulfan (30 g/m(2), n=5) or melphalan (100-150 mg/m(2), n=12). Patients were also given serotherapy, ATG (n=32), or alemtuzumab (n=4). The probabilities of overall survival, disease-free survival, and nonrelapse mortality at 1 year after SCT were 52, 43, and 39%, respectively. Acute graft-versus-host disease (GVHD) grade II-IV and chronic GVHD occurred in 31 and 45%, respectively. Multivariable analysis determined that survival rates were higher in patients with chemosensitive disease (HR 4.5), and patients conditioned with intravenous busulfan or treosulfan (HR 3.9). Unrelated donor SCT is feasible in elderly patients, with outcomes that are similar to younger patients. Favorable outcome was observed in patients with myeloid malignancies, and those transplanted in remission and early in the course of disease. Age alone should not be considered a contraindication to unrelated donor SCT.

Myotonic dystrophy gene analysis in affected Israeli families.

Myotonic dystrophy (DM) is an autosomal dominant disease with an estimated incidence of 1:7,500 individuals. The clinical manifestations are variable and include muscle wasting and weakness, myotonia, intellectual impairment, cardiac abnormalities, cataracts, and testicular atrophy. Despite its phenotypic variability, the disease is genetically homogeneous, and a specific molecular defect has been located to chromosome 19q13.3 and found to be associated with the expansion and instability of trinucleotide (CTG) repeats. Whereas normal individuals have 5-36 CTG repeats, affected individuals have 50 to several thousands. Therefore, DM can now be diagnosed accurately using molecular biology techniques that allow detailed analysis and determination of the size of DNA in the unstable DM gene region. In this way even mildly affected patients can be identified. We used this method to study the DM gene in 11 affected Israeli families (39 individuals). In most of the families, the unstable DNA sequence increased in size when transmitted to offspring. In one of the families we found contraction of the CTG repeat in a DM offspring of an affected male; and in another family a CTG repeat contraction occurred in three offspring of an affected female while in the fourth offspring there was CTG expansion. Southern blot analysis using BglI restriction provided the most accurate technical results. There was an obvious phenotype/genotype correlation between the size of the CTG repeat and severity of disease.