Marco Mielcarek

Graft-Versus-Tumor Effects After Allogeneic Hematopoietic Cell Transplantation With Nonmyeloablative Conditioning

PURPOSE We have used a nonmyeloablative conditioning regimen consisting of total-body irradiation (2 Gy) with or without fludarabine (30 mg/m(2)/d for 3 days) for related and unrelated hematopoietic cell transplantation (HCT) in patients with hematologic malignancies who were not candidates for conventional HCT because of age, medical comorbidities, or preceding high-dose HCT. This approach relied on graft-versus-tumor (GVT) effects for control of malignancy. PATIENTS AND METHODS We analyzed GVT effects in 322 patients given grafts from HLA-matched related (n = 192) or unrelated donors (n = 130). RESULTS Of the 221 patients with measurable disease at HCT, 126 (57%) achieved complete (n = 98) or partial (n = 28) remissions. In multivariate analysis, there was a higher probability trend of achieving complete remissions in patients with chronic extensive graft-versus-host disease (GVHD; P = .07). One hundred eight patients (34%) relapsed or progressed. In multivariate analysis, achievement of full donor chimerism was associated with a decreased risk of relapse or progression (P = .002). Grade 2 to 4 acute GVHD had no significant impact on the risk of relapse or progression but was associated with increased risk of nonrelapse mortality and decreased probability of progression-free survival (PFS). Conversely, extensive chronic GVHD was associated with decreased risk of relapse or progression (P = .006) and increased probability of PFS (P = .003). CONCLUSION New approaches aimed at reducing the incidence of grade 2 to 4 acute GVHD might improve survival after allogeneic HCT after nonmyeloablative conditioning.

Comparative analysis of risk factors for acute graft-versus-host disease and for chronic graft-versus-host disease according to National Institutes of Health consensus criteria

Risk factors for grades 2-4 acute graft-versus-host disease (GVHD) and for chronic GVHD as defined by National Institutes of Health consensus criteria were evaluated and compared in 2941 recipients of first allogeneic hematopoietic cell transplantation at our center. In multivariate analyses, the profiles of risk factors for acute and chronic GVHD were similar, with some notable differences. Recipient human leukocyte antigen (HLA) mismatching and the use of unrelated donors had a greater effect on the risk of acute GVHD than on chronic GVHD, whereas the use of female donors for male recipients had a greater effect on the risk of chronic GVHD than on acute GVHD. Total body irradiation was strongly associated with acute GVHD, but had no statistically significant association with chronic GVHD, whereas grafting with mobilized blood cells was strongly associated with chronic GVHD but not with acute GVHD. Older patient age was associated with chronic GVHD, but had no effect on acute GVHD. For all risk factors associated with chronic GVHD, point estimates and confidence intervals were not significantly changed after adjustment for prior acute GVHD. These results suggest that the mechanisms involved in acute and chronic GVHD are not entirely congruent and that chronic GVHD is not simply the end stage of acute GVHD.

Long-term outcomes among older patients following nonmyeloablative conditioning and allogeneic hematopoietic cell transplantation for advanced hematologic malignancies

CONTEXT A minimally toxic nonmyeloablative regimen was developed for allogeneic hematopoietic cell transplantation (HCT) to treat patients with advanced hematologic malignancies who are older or have comorbid conditions. OBJECTIVE To describe outcomes of patients 60 years or older after receiving minimally toxic nonmyeloablative allogeneic HCT. DESIGN, SETTING, AND PARTICIPANTS From 1998 to 2008, 372 patients aged 60 to 75 years were enrolled in prospective clinical HCT trials at 18 collaborating institutions using conditioning with low-dose total body irradiation alone or combined with fludarabine, 90 mg/m(2), before related (n = 184) or unrelated (n = 188) donor transplants. Postgrafting immunosuppression included mycophenolate mofetil and a calcineurin inhibitor. MAIN OUTCOME MEASURES Overall and progression-free survival were estimated by Kaplan-Meier method. Cumulative incidence estimates were calculated for acute and chronic graft-vs-host disease, toxicities, achievement of full donor chimerism, complete remission, relapse, and nonrelapse mortality. Hazard ratios (HRs) were estimated from Cox regression models. RESULTS Overall, 5-year cumulative incidences of nonrelapse mortality and relapse were 27% (95% CI, 22%-32%) and 41% (95% CI, 36%-46%), respectively, leading to 5-year overall and progression-free survival of 35% (95% CI, 30%-40%) and 32% (95% CI, 27%-37%), respectively. These outcomes were not statistically significantly different when stratified by age groups. Furthermore, increasing age was not associated with increases in acute or chronic graft-vs-host disease or organ toxicities. In multivariate models, HCT-specific comorbidity index scores of 1 to 2 (HR, 1.58 [95% CI, 1.08-2.31]) and 3 or greater (HR, 1.97 [95% CI, 1.38-2.80]) were associated with worse survival compared with an HCT-specific comorbidity index score of 0 (P = .003 overall). Similarly, standard relapse risk (HR, 1.67 [95% CI, 1.10-2.54]) and high relapse risk (HR, 2.22 [95% CI, 1.43-3.43]) were associated with worse survival compared with low relapse risk (P < .001 overall). CONCLUSION Among patients aged 60 to 75 years treated with nonmyeloablative allogeneic HCT, 5-year overall and progression-free survivals were 35% and 32%, respectively.

CMV reactivation after allogeneic HCT and relapse risk: evidence for early protection in acute myeloid leukemia

The association between cytomegalovirus (CMV) reactivation and relapse was evaluated in a large cohort of patients with acute myeloid leukemia (AML) (n = 761), acute lymphoblastic leukemia (ALL) (n = 322), chronic myeloid leukemia (CML) (n = 646), lymphoma (n = 254), and myelodysplastic syndrome (MDS) (n = 371) who underwent allogeneic hematopoietic cell transplantation (HCT) between 1995 and 2005. In multivariable models, CMV pp65 antigenemia was associated with a decreased risk of relapse by day 100 among patients with AML (hazard ratio [HR] = 0.56; 95% confidence interval [CI], 0.3-0.9) but not in patients with ALL, lymphoma, CML, or MDS. The effect appeared to be independent of CMV viral load, acute graft-versus-host disease, or ganciclovir-associated neutropenia. At 1 year after HCT, early CMV reactivation was associated with reduced risk of relapse in all patients, but this did not reach significance for any disease subgroup. Furthermore, CMV reactivation was associated with increased nonrelapse mortality (HR = 1.31; 95% CI, 1.1-1.6) and no difference in overall mortality (HR = 1.05; 95% CI, 0.9-1.3). This report demonstrates a modest reduction in early relapse risk after HCT associated with CMV reactivation in a large cohort of patients without a benefit in overall survival.

Graft-Versus-Host Disease and Graft-Versus-Tumor Effects After Allogeneic Hematopoietic Cell Transplantation

PURPOSE We designed a minimal-intensity conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) in patients with advanced hematologic malignancies unable to tolerate high-intensity regimens because of age, serious comorbidities, or previous high-dose HCT. The regimen allows the purest assessment of graft-versus-tumor (GVT) effects apart from conditioning and graft-versus-host disease (GVHD) not augmented by regimen-related toxicities. PATIENTS AND METHODS Patients received low-dose total-body irradiation ± fludarabine before HCT from HLA-matched related (n = 611) or unrelated (n = 481) donors, followed by mycophenolate mofetil and a calcineurin inhibitor to aid engraftment and control GVHD. Median patient age was 56 years (range, 7 to 75 years). Forty-five percent of patients had comorbidity scores of ≥ 3. Median follow-up time was 5 years (range, 0.6 to 12.7 years). RESULTS Depending on disease risk, comorbidities, and GVHD, lasting remissions were seen in 45% to 75% of patients, and 5-year survival ranged from 25% to 60%. At 5 years, the nonrelapse mortality (NRM) rate was 24%, and the relapse mortality rate was 34.5%. Most NRM was a result of GVHD. The most significant factors associated with GVHD-associated NRM were serious comorbidities and grafts from unrelated donors. Most relapses occurred early while the immune system was compromised. GVT effects were comparable after unrelated and related grafts. Chronic GVHD, but not acute GVHD, further increased GVT effects. The potential benefit associated with chronic GVHD was outweighed by increased NRM. CONCLUSION Allogeneic HCT relying on GVT effects is feasible and results in cures of an appreciable number of malignancies. Improved results could come from methods that control progression of malignancy early after HCT and effectively prevent GVHD.

Initial therapy of acute graft-versus-host disease with low-dose prednisone does not compromise patient outcomes

We hypothesized that initial treatment of acute graft-versus-host disease (GVHD) with low-dose glucocorticoids (prednisone-equivalent dose of 1 mg/kg per day) instead of standard-dose glucocorticoids (prednisone-equivalent dose of 2 mg/kg per day) does not compromise major transplantation outcomes. We retrospectively analyzed outcomes among 733 patients who received transplants between 2000 and 2005 according to initial treatment with low-dose (n=347) versus standard-dose (n=386) systemic glucocorticoids. The mean cumulative prednisone-equivalent doses at day 100 after starting treatment were 44 and 87 mg/kg for patients given low-dose and standard-dose glucocorticoids, respectively. Adjusted outcomes between the groups given low-dose versus standard-dose glucocorticoids were not statistically significantly different: overall mortality (hazard ratio [HR], 1.10; 95% confidence interval [CI], 0.9-1.4), relapse (HR, 1.22; 95% CI, 0.9-1.7), nonrelapse mortality (HR, 1.06; 95% CI, 0.8-1.5). The small number of patients with grades III/IV acute GVHD at onset precluded definitive conclusions for this subgroup. In multivariate analysis, the risks of invasive fungal infections (HR, 0.59; 95% CI, 0.3-1.0) and the duration of hospitalization (odds ratio, 0.62; 95% CI, 0.4-0.9) were reduced in the low-dose prednisone group. We conclude that initial treatment with low-dose glucocorticoids for patients with grades I-II GVHD did not compromise disease control or mortality and was associated with decreased toxicity.

Multi-Institutional Study of Post-Transplantation Cyclophosphamide As Single-Agent Graft-Versus-Host Disease Prophylaxis After Allogeneic Bone Marrow Transplantation Using Myeloablative Busulfan and Fludarabine Conditioning

PURPOSE The clinical safety and efficacy of intravenous busulfan and fludarabine (IV Bu/Flu) myeloablative conditioning as well as graft-versus-host disease (GVHD) prophylaxis with high-dose, post-transplantation cyclophosphamide (PTCy) have been demonstrated independently in several single-institutional studies. We hypothesized that combining these two promising approaches in a multi-institutional study of human leukocyte antigen (HLA) -matched bone marrow transplantation would provide low rates of severe acute and chronic GVHD, low toxicity, and effective disease control. PATIENTS AND METHODS Ninety-two adult patients (median age, 49 years; range, 21 to 65 years) with high-risk hematologic malignancies were enrolled at three centers (clinical trial No. NCT00809276). Forty-five patients received related allografts, and 47 received unrelated allografts. GVHD prophylaxis was solely with PTCy at 50 mg/kg/day on post-transplantation days +3 and +4. RESULTS The cumulative incidences of grades 2 to 4 acute, grades 3 to 4 acute, and chronic GVHD were 51%, 15%, and 14%, respectively. Nonrelapse mortality (NRM) at 100 days and 1 year were 9% and 16%, respectively. With a median follow-up period of 2.2 years, the 2-year disease-free survival (DFS) and overall survival (OS) rates were 62% and 67%, respectively. Donor relatedness did not affect NRM, DFS, or OS. Patients in complete remission (CR) without evidence of minimal residual disease (MRD) had markedly better DFS (80%) and OS (80%) than patients in CR with MRD or with active disease at the time of transplantation (DFS, P = .0005; OS, P = .019). CONCLUSION This multi-institutional study demonstrates that PTCy can be safely and effectively combined with IV Bu/Flu myeloablative conditioning and confirms PTCys efficacy as single-agent, short-course GVHD prophylaxis for both acute and chronic GVHD after bone marrow transplantation from HLA-matched donors.

Cord-Blood Transplantation in Patients with Minimal Residual Disease

BACKGROUND The majority of patients in need of a hematopoietic-cell transplant do not have a matched related donor. Data are needed to inform the choice among various alternative donor-cell sources. METHODS In this retrospective analysis, we compared outcomes in 582 consecutive patients with acute leukemia or the myelodysplastic syndrome who received a first myeloablative hematopoietic-cell transplant from an unrelated cord-blood donor (140 patients), an HLA-matched unrelated donor (344), or an HLA-mismatched unrelated donor (98). RESULTS The relative risks of death and relapse between the cord-blood group and the two other unrelated-donor groups appeared to vary according to the presence of minimal residual disease status before transplantation. Among patients with minimal residual disease, the risk of death was higher in the HLA-mismatched group than in the cord-blood group (hazard ratio, 2.92; 95% confidence interval [CI], 1.52 to 5.63; P=0.001); the risk was also higher in the HLA-matched group than in the cord-blood group but not significantly so (hazard ratio, 1.69; 95% CI, 0.94 to 3.02; P=0.08). Among patients without minimal residual disease, the hazard ratios were lower (hazard ratio in the HLA-mismatched group, 1.36; 95% CI, 0.76 to 2.46; P=0.30; hazard ratio in the HLA-matched group, 0.78; 95% CI, 0.48 to 1.28; P=0.33). The risk of relapse among patients with minimal residual disease was significantly higher in the two unrelated-donor groups than in the cord-blood group (hazard ratio in the HLA-mismatched group, 3.01; 95% CI, 1.22 to 7.38; P=0.02; hazard ratio in the HLA-matched group, 2.92; 95% CI, 1.34 to 6.35; P=0.007). Among patients without minimal residual disease, the magnitude of these associations was lower (hazard ratio in the HLA-mismatched group, 1.28; 95% CI, 0.51 to 3.25; P=0.60; hazard ratio in the HLA-matched group, 1.30; 95% CI, 0.65 to 2.58; P=0.46). CONCLUSIONS Our data suggest that among patients with pretransplantation minimal residual disease, the probability of overall survival after receipt of a transplant from a cord-blood donor was at least as favorable as that after receipt of a transplant from an HLA-matched unrelated donor and was significantly higher than the probability after receipt of a transplant from an HLA-mismatched unrelated donor. Furthermore, the probability of relapse was lower in the cord-blood group than in either of the other groups.

Pre- and post-transplant quantification of measurable ('minimal') residual disease via multiparameter flow cytometry in adult acute myeloid leukemia.

Measurable (‘minimal’) residual disease (MRD) before or after hematopoietic cell transplantation (HCT) identifies adults with AML at risk of poor outcomes. Here, we studied whether peri-transplant MRD dynamics can refine risk assessment. We analyzed 279 adults receiving myeloablative allogeneic HCT in first or second remission who survived at least 35 days and underwent 10-color multiparametric flow cytometry (MFC) analyses of marrow aspirates before and 28±7 days after transplantation. MFC-detectable MRD before (n=63) or after (n=16) transplantation identified patients with high relapse risk and poor survival. Forty-nine patients cleared MRD with HCT conditioning, whereas two patients developed new evidence of disease. The 214 MRDneg/MRDneg patients had excellent outcomes, whereas both MRDneg/MRDpos patients died within 100 days following transplantation. For patients with pre-HCT MRD, outcomes were poor regardless of post-HCT MRD status, although survival beyond 3 years was only observed among the 58 patients with decreasing but not the seven patients with increasing peri-HCT MRD levels. In multivariable models, pre-HCT but not post-HCT MRD was independently associated with overall survival and risk of relapse. These data indicate that MRDpos patients before transplantation have a high relapse risk regardless of whether or not they clear MFC-detectable disease with conditioning and should be considered for pre-emptive therapeutic strategies.

Donor statin treatment protects against severe acute graft-versus-host disease after related allogeneic hematopoietic cell transplantation

We retrospectively analyzed outcomes among 567 patients with hematologic malignancies who had hematopoietic cell transplantation from human leukocyte antigen-identical sibling donors between 2001 and 2007 for a correlation between statin use and risk of graft-versus-host disease (GVHD). Compared with allografts where neither the donor nor recipient was treated with a statin at the time of transplantation (n = 464), statin use by the donor and not the recipient (n = 75) was associated with a decreased risk of grade 3-4 acute GVHD (multivariate hazard ratio, 0.28; 95% confidence interval, 0.1-0.9). Statin use by both donor and recipient (n = 12) was suggestively associated with a decreased risk of grade 3 or 4 acute GVHD (multivariate hazard ratio, 0.00; 95% confidence interval, undefined), whereas statin use by the recipient and not the donor (n = 16) did not confer GVHD protection. Risks of chronic GVHD, recurrent malignancy, nonrelapse mortality, and overall mortality were not significantly affected by donor or recipient statin exposure. Statin-associated GVHD protection was restricted to recipients with cyclosporine-based postgrafting immunosuppression and was not observed among those given tacrolimus (P = .009). These results suggest that donor statin treatment may be a promising strategy to prevent severe acute GVHD without compromising immunologic control of the underlying malignancy.