Andrea Bacigalupo

DEFINING THE INTENSITY OF CONDITIONING REGIMENS : working definitions

Defining conditioning regimen intensity has become a critical issue for the hemopoietic stem cell transplant (HSCT) community. In the present report we propose to define conditioning regimens in 3 categories: (1) myeloablative (MA) conditioning, (2) reduced-intensity conditioning (RIC), and (3) nonmyeloablative (NMA) conditioning. Assignment to these categories is based on the duration of cytopenia and on the requirement for stem cell (SC) support: MA regimens cause irreversible cytopenia and SC support is mandatory. NMA regimens cause minimal cytopenia, and can be given also without SC support. RIC regimens do not fit criteria for MA or NMA regimens: they cause cytopenia of variable duration, and should be given with stem cell support, although cytopenia may not be irreversible. This report also assigns commonly used regimens to one of these categories, based upon the agents, dose, or combinations. Standardized classification of conditioning regimen intensities will allow comparison across studies and interpretation of study results.

Malignant Tumors Occurring after Treatment of Aplastic Anemia

BACKGROUND AND METHODS Recent studies have shown that long-term survivors of acquired aplastic anemia may be at high risk for malignant diseases. We assessed the risk of cancer after aplastic anemia was treated with immunosuppression or bone marrow transplantation and sought to identify risk factors according to treatment. The study population consisted of 860 patients treated by immunosuppression and 748 patients who had received bone marrow transplants for the treatment of severe aplastic anemia. The risk of cancer was analyzed overall and according to treatment relative to the risk in the general population. In calculating relative risk, we excluded patients with myelodysplastic syndromes or acute leukemias arising less than 6 months after treatment, and solid cancers arising less than 12 months after treatment, because of a possible association with aplastic anemia itself rather than with the treatment received. RESULTS Forty-two malignant conditions were reported in the 860 patients who received immunosuppressive therapy: 19 cases of myelodysplastic syndrome, 15 cases of acute leukemia, 1 case of non-Hodgkins lymphoma, and 7 solid tumors. Nine were reported in the 748 patients who received bone marrow transplants: two cases of acute leukemia and seven solid tumors. After the exclusions listed above, the overall relative risk of cancer was 5.50 (P < 0.001) as compared with that in the general European population; the risk was 5.15 (P < 0.001) after immunosuppressive therapy and 6.67 (P < 0.001) after transplantation. The 10-year cumulative incidence rate of cancer was 18.8 percent after immunosuppressive therapy and 3.1 percent after transplantation. The risk factors for myelodysplastic syndrome or acute leukemia after immunosuppressive therapy included the addition of androgens to the immunosuppressive treatment (relative risk = 0.28), older age (relative risk = 1.03), treatment in 1982 or later, as compared with 1981 or earlier (relative risk = 3.01), splenectomy (relative risk = 3.65), and treatment with multiple courses of immunosuppression (relative risk = 2.26). Risk factors for solid tumors after bone marrow transplantation were age (relative risk = 1.11 per year) and the use of radiation as a conditioning regimen before transplantation (relative risk = 9.56); such tumors occurred only in male patients. CONCLUSIONS Survivors of aplastic anemia are at high risk for subsequent malignant conditions. Myelodysplastic syndrome and acute leukemia tend to follow immunosuppressive therapy, whereas the incidence of solid tumors is similar after immunosuppression and after bone marrow transplantation.

Allogeneic bone marrow transplantation vs filgrastim-mobilised peripheral blood progenitor cell transplantation in patients with early leukaemia: first results of a randomised multicentre trial of the European Group for Blood and Marrow Transplantation

In a multicentre trial involving 20 transplant centres from 10 countries haematopoietic stem cells were obtained either from the bone marrow of 33 sibling donors or from the peripheral blood of 33 such donors after administration of filgrastim (10 μg/kg/day). The haematopoietic stem cells were infused into their HLA-identical recipients suffering from acute leukaemias in remission or chronic myeloid leukaemia in chronic phase. PBPC donors tolerated filgrastim administration and leukapheresis well with the most frequent side-effects being musculoskeletal pain, headache, and mild increases of LDH, AP, Gamma-GT or SGPT. Pain and haematoma at the harvest site and mild anaemia were the most frequent complaints of BM donors. Severe or life-threatening complications were not seen with any type of harvest procedure. Time to platelet recovery greater than 20 × 109/l was 15 days (95% confidence interval (CI) 13–16 days) in the PBPCT group and 19 days (CI 16–25) in the BMT group. Time to neutrophil recovery greater than 0.5 × 109/l was 14 days (CI 12–15 days) in the PBPCT group as compared to 15 days (CI 15–16 days) in the BMT group. The numbers of platelet transfusions administered to PBPCT and BMT patients were 12 (range: 1–28) and 10 (range: 3–39), respectively. Sixteen patients (48%) transplanted with bone marrow and 18 patients (54%) transplanted with PBPC developed acute GVHD of grades II–IV; acute GVHD of grades III or IV developed in six (18%) and seven (21%) patients, respectively. Kaplan–Meier plots for transplant-related mortality until day 100 and leukaemia-free survival at a median of 400 days after BMT or PBPCT showed no significant differences. Administration of filgrastim and leukapheresis in normal donors were feasible and well tolerated. The number of days with restricted activity and of nights spent in hospital was lower in donors of PBPC. Transplantation of PBPC to HLA-identical siblings with early leukaemia resulted in earlier platelet engraftment. The incidence of moderate to severe acute GVHD, transplant-related mortality, and leukaemia-free survival did not show striking differences. Further investigation of allogeneic PBPCT as a substitute for allogeneic BMT is warranted.

STROMAL DAMAGE AS CONSEQUENCE OF HIGH-DOSE CHEMO/RADIOTHERAPY IN BONE MARROW TRANSPLANT RECIPIENTS

Bone marrow transplant (BMT) relies on the engraftment of donor hemopoietic precursors in the host marrow space. Colony forming units-fibroblasts (CFU-f), the precursor compartment for the osteogenic lineage, are essential to hemopoietic stem cell survival, proliferation and differentiation. We have studied CFU-f in donors (aged 5 months to 62 years) and in patients who had received allogeneic BMT (aged 2 months to 63 years). In donor marrows we found an inverse correlation between CFU-f frequency and age. In BMT recipients CFU-f frequencies were reduced by 60%-90% (p < 0.05) and the numbers did not recover up to 12 years after transplant. Stromal reconstitution to normal levels was found only in patients < 5 years old. In all patients studied CFU-f post-BMT were of host origin. Patients with low CFU-f levels displayed also a decreased bone mineral density (p < 0.05) and significantly reduced levels of long-term culture-initiating cells (LTC-IC) (p < 0.05). Our study demonstrates that the marrow stromal microenvironment is seriously and irreversibly damaged after BMT. Donor cells do not contribute to reconstitute the marrow microenvironment, whose residual CFU-fs remain of host origin.

False-Positive Galactomannan Platelia Aspergillus Test Results for Patients Receiving Piperacillin-Tazobactam

At the bone marrow transplantation center of the San Martino Hospital (Genoa), we observed an increase in the rate of patients with positive Platelia Aspergillus (PA; Bio-Rad) test results, from 10% (38 of 386 patients) in the period from January 1999 through January 2003 to 36% (21 of 59 patients) in the period from February 2003 through May 2003. Positivity was significantly (P<.001) associated with the administration of piperacillin-tazobactam (PT) (17 [74%] of 23 patients who received PT had positive results vs. 4 [11%] of 36 who did not receive PT). Multivariate analysis found administration of PT ( chi 2=34.7; P<.001) and underlying disease ( chi 2=21.14; P<.001) to be associated with PA positivity. Of 15 PT batches tested, 12 had positive PA test results.

Direct intrabone transplant of unrelated cord-blood cells in acute leukaemia: a phase I/II study

BACKGROUND Cord-blood transplants are associated with delayed or failed engraftment in about 20% of adult patients. The aim of this phase I/II study was to establish the safety and efficacy of a new administration route (intrabone) for cord-blood cells, measured by the donor-derived neutrophil and platelet engraftment. METHODS Adult patients with acute leukaemia, for whom an unrelated stem-cell transplantation was indicated and no suitable unrelated human leucocyte antigen (HLA)-matched donor had been identified, were included in the study and underwent a cord-blood transplant in San Martino Hospital, Genoa, Italy. Eight patients were in first complete remission, ten in second complete remission, and 14 had advanced-stage, refractory disease. HLA matching was 5/6, 4/6, and 3/6 for 9, 22, and one patient, respectively. Cord-blood cells were concentrated in four 5-mL syringes, and were infused in the superior-posterior iliac crest under rapid general anaesthesia. Median transplanted cell dose was 2.6 x 10(7)/kg (range 1.4-4.2). The primary endpoint was the probability of neutrophil and platelet recovery after intrabone cord-blood transplantantion. Secondary endpoints included the incidence of acute graft-versus-host disease, relapse, and overall survival. This trial is registered on the ClinicalTrials.gov website, number NCT 00696046. FINDINGS Between March 31, 2006, and Jan 25, 2008, 32 consecutive patients with acute myeloid leukaemia (n=20) or acute lymphoblastic leukaemia (n=12) underwent a cord-blood transplant (median age 36 years [range 18-66]). No complications occurred during or after the intrabone infusion of cells. Four patients with advanced-stage disease died within 12 days of the procedure. Median time to recovery of neutrophils in 28 patients (>/=0.5 x 10(9)/L) was 23 days (range 14-44) and median time to recovery of platelets in 27 patients (>/=20 x 10(9)/L) was 36 days (range 16-64). All patients were fully chimeric from 30 days after transplantation to the last follow-up visit, suggesting an early complete donor engraftment. No patient developed grade III-IV acute graft-versus-host disease. Causes of death were transplant related (n=5), infection (n=7), and relapse (n=4). 16 patients were alive and in haematological remission at a median follow-up of 13 months (range 3-23). INTERPRETATION Our preliminary data suggest that direct intrabone cord-blood transplantation overcomes the problem of graft failure even when low numbers of HLA-mismatched cord-blood cells are transplanted, thus leading to the possibility of use of this technique in a large number of adult patients.

Haematopoietic stem cell transplantation for patients with myelo- dysplastic syndromes and secondary acute myeloid leukaemias: a report on behalf of the Chronic Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT)

Allogeneic stem cell transplantation from an HLA‐identical sibling donor is a curative treatment option for a young patient with myelodysplastic syndrome, limited by age and lack of sibling donors. Alternative stem cell sources have been used more recently, such as unrelated donors, non‐identical family members or autologous transplants. This analysis of 1378 transplants reported to the European Group for Blood and Marrow Transplantation (EBMT) addresses the outcome of the varying procedures according to the known risk factors. The estimated disease‐free survival (DFS) and estimated relapse risk at 3 years were both 36% for 885 patients transplanted with stem cells from matched siblings. In the multivariate analysis, age and stage of disease had independent prognostic significance for DFS, survival and treatment‐related mortality. Patients transplanted at an early stage of disease had a significantly lower risk of relapse than patients transplanted at more advanced stages. The estimated DFS at 3 years was 25% for the 198 patients with voluntary unrelated donors, 28% for the 91 patients with alternative family donors and 33% for the 126 patients autografted in first complete remission. The non‐relapse mortality was 58% for patients with unrelated donors, 66% for patients with non‐identical family donors and 25% for autografted patients. The relapse rate of 18% was relatively low for patients with non‐identical family donors, 41% for patients with unrelated donors and 55% for patients treated with autologous stem cell transplantation. Both allogeneic and autologous stem cell transplantation have emerged as treatment options for patients with myelodysplastic syndromes. Transplantation with an HLA‐identical sibling donor is the preferred treatment option. Patients without an HLA‐identical sibling donor may be treated with either autologous stem cell transplantation or an alternative donor transplantation. Patients younger than 20 years may be treated with an unrelated donor transplantation. Patients older than 40 years, and probably also patients between 20 and 40 years, may benefit most from an autologous stem cell transplantation.

A multicenter prospective phase 2 randomized study of extracorporeal photopheresis for treatment of chronic graft-versus-host disease

Chronic graft-versus-host disease (cGVHD) is a major limitation of successful hematopoietic cell transplantation. The safety and efficacy of extracorporeal photopheresis (ECP) for 12 to 24 weeks together with standard therapy was compared with standard therapy alone in patients with cutaneous manifestations of cGVHD that could not be adequately controlled by corticosteroid treatment. The primary efficacy end point was a blinded quantitative comparison of percent change from baseline in Total Skin Score (TSS) of 10 body regions at week 12. Ninety-five patients were randomized to either ECP and standard therapy (n = 48) or standard therapy alone (n = 47). The median percentage improvement in TSS at week 12 was 14.5% for the ECP arm and 8.5% for the control arm (P = .48). The proportion of patients who had at least a 50% reduction in steroid dose and at least a 25% decrease from baseline in TSS was 8.3% in the ECP arm at week 12 and 0% in the control arm (P = .04). The nonblinded investigator assessment of skin complete or partial responses revealed a significant improvement in favor of ECP (P < .001). ECP was generally well tolerated. These results suggest that ECP may have a steroid-sparing effect in the treatment of cGVHD. Clinical trials registered at www.ClinicalTrials.gov as NCT00054613.

Unmanipulated Haploidentical Bone Marrow Transplantation and Posttransplantation Cyclophosphamide for Hematologic Malignancies after Myeloablative Conditioning

Fifty patients with high-risk hematologic malignancies, underwent an unmanipulated haploidentical bone marrow transplantation (BMT), followed by posttransplantation high-dose cyclophosphamide (PT-CY): the myeloablative (MA) conditioning consisted of thiotepa, busulfan, fludarabine (n = 35), or total body irradiation (TBI), fludarabine (n = 15). The median age was 42 years (range, 18-66 years); 23 patients were in remission, 27 had active disease, and 10 patients were receiving a second allograft. Graft-versus-host disease (GVHD) prophylaxis consisted in PT-CY on day +3 and +5, cyclosporine (from day 0), and mycophenolate (from day +1). Three patients died before engraftment, and 2 patients had autologous recovery: 45 patients (90%) had full-donor chimerism on day +30. The median day for neutrophil engraftment was day +18 (range, 13-30 days). The cumulative incidence of grade II-III acute GVHD (aGVHD) was 12%, and of moderate chronic GVHD (cGVHD) 10%. With a median follow-up for surviving patients of 333 days (range, 149-623 days), the cumulative incidence of transplantation-related mortality (TRM) was 18%, and the rate of relapse was 26%. The actuarial 22-month disease-free survival (DFS) rate was 68% for patients in remission and 37% for patients with active disease (P < .001). Causes of death were pneumonia (n = 3), hemorrhage (n = 3), sepsis (n = 3), and relapse (n = 7). In conclusion, an MA conditioning regimen followed by haploidentical BMT with PT-CY results in a low risk of aGVHD and cGVHD and encouraging rates of TRM and DFS.

Allogeneic Hematopoietic Stem-Cell Transplantation for Patients 50 Years or Older With Myelodysplastic Syndromes or Secondary Acute Myeloid Leukemia

PURPOSE This study was performed to examine the characteristics of transplant activity for patients with myelodysplastic syndromes (MDS) older than 50 years within the European Group for Blood and Marrow Transplantation, and to evaluate the factors predicting outcome within this group of patients. PATIENTS AND METHODS We performed a retrospective multicenter analysis of 1,333 MDS patients age 50 years or older who received transplantation within the EBMT since 1998. The median recipient age was 56 years, with 884 patients (66%) age 50 to 60 years and 449 (34%) patients older than 60 years. There were 811 HLA-matched sibling (61%) and 522 (39%) unrelated donor transplants. Five hundred patients (38%) received standard myeloablative conditioning (SMC), and 833 (62%) received reduced intensity conditioning (RIC). RESULTS The 4-year estimate for overall survival of the whole cohort was 31%. On multivariate analysis, use of RIC (hazard ratio [HR], 1.44; 95% CI, 1.13 to 1.84; P < .01) and advanced disease stage at transplantation (HR, 1.51; 95% CI, 1.18 to 1.93; P < .01) were associated with an increased relapse rate. In contrast, advanced disease stage at transplantation (HR, 1.43; 95% CI, 1.13 to 1.79; P = .01), use of an unrelated donor (P = .03), and RIC (HR, 0.79; 95% CI, 0.65 to 0.97; P = .03) were independent variables associated with nonrelapse mortality. Advanced disease stage at transplantation (HR, 1.55; 95% CI, 1.32 to 1.83; P < .01) was the major independent variable associated with an inferior 4-year overall survival. CONCLUSION Allogeneic hematopoietic stem-cell transplantation remains a potential curative therapeutic option for many older patients with MDS. In this analysis, disease stage at time of transplantation, but not recipient age or the intensity of the conditioning regimens, was the most important factor influencing outcomes.