Nicoletta Sacchi

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.

Nonpermissive HLA-DPB1 disparity is a significant independent risk factor for mortality after unrelated hematopoietic stem cell transplantation

The importance of donor-recipient human leukocyte antigen (HLA)-DPB1 matching for the clinical outcome of unrelated hematopoietic stem cell transplantation (HSCT) is controversial. We have previously described an algorithm for nonpermissive HLA-DPB1 disparities involving HLA-DPB1*0901,*1001,*1701,*0301,*1401,*4501, based on T-cell alloreactivity patterns. By revisiting the immunogenicity of HLA-DPB1*02, a modified algorithm was developed and retrospectively tested in 621 unrelated HSCTs facilitated through the Italian Registry for oncohematologic adult patients. The modified algorithm proved to be markedly more predictive of outcome than the original one, with significantly higher Kaplan-Meier probabilities of 2-year survival in permissive compared with nonpermissive transplantations (55% vs 39%, P = .005). This was the result of increased adjusted hazards of nonrelapse mortality (hazard ratio [HR] = 1.74; confidence interval [CI], 1.19-2.53; P = .004) but not of relapse (HR = 1.02; CI, 0.73-1.42; P = .92). The increase in the hazards of overall mortality by nonpermissive HLA-DPB1 disparity was similar in 10 of 10 (HR = 2.12; CI, 1.23-3.64; P = .006) and 9 of 10 allele-matched transplantations (HR = 2.21; CI, 1.28-3.80; P = .004), both in early-stage and in advanced-stage disease. These data call for revisiting current HLA matching strategies for unrelated HSCT, suggesting that searches should be directed up-front toward identification of HLA-DPB1 permissive, 10 of 10 or 9 of 10 matched donors.

Bone marrow transplantation for chronic myeloid leukemia (CML) from unrelated and sibling donors: single center experience

This is a report on 60 consecutive patients with chronic myeloid leukemia (CML) who received an allogeneic bone marrow transplant (BMT) in this Unit. Donors were HLA-identical siblings (SIB) (n = 36) or unrelated donors (MUD) (n = 24) matched by serology for HLA A and B and by molecular biology for HLA DR. All patients were prepared with cyclophosphamide 120 mg/kg and fractionated total body irradiation 10–12 Gy. GVHD prophylaxis consisted of cyclosporin A (CsA) starting on day −7 and short-course methotrexate. Bone marrow was unmanipulated in all cases. Cytomegalovirus prophylaxis consisted of acyclovir for SIBs and foscarnet for MUDs. When compared to SIB transplants, MUD patients were younger (29 vs 36 years; P = 0.002), had younger donors (31 vs 39; P = 0.001), had a longer interval between diagnosis and BMT (1459 vs 263 days; P < 0.001) and received a smaller number of nucleated cells at transplant (3.3 vs 4.4 × 108/kg; P = 0.003). More MUDs had advanced disease (50 vs 17%, P = 0.005). The median day to 0.5 × 109/l neutrophils was similar in both groups (18 days for SIBs vs 17 days for MUDs; P = 0.06); the median platelet count on days +30, +50, +100 was significantly (P < 0.01) higher in sib than in mud patients (122 vs 38, 113 vs 50 and 97 vs 45 × 109/l, respectively). Acute GVHD was scored as absent-mild, moderate, or severe, in 36, 58 and 6% of SIBs vs 25, 42 and 33% in MUD patients (P = 0.01). Chronic GVHD was comparable (P = 0.1). The actuarial risk of CMV antigenemia at 1 year was 60% in both groups. There were six deaths in SIB patients (two leukemia, two infections, one GVHD, one pneumonitis) and four deaths in MUD patients (three acute GVHD and one infection). Fifty patients survive with a median follow-up of 656 days for SIBs and 485 for MUDs. The actuarial 3-year transplant-related mortality is 12% in SIBs and 17% in MUDs (P = 0.5); the actuarial relapse is 18% in SIBs vs 6% in MUDs (P = 0.4) and 3-year survival 78% in SIBs vs 82% in MUDs (P = 0.7). This study suggests that survival of CML patients after marrow transplantation from unrelated or sibling donors is currently similar, provided the former are well matched. The increased incidence of GVHD in MUD patients is possibly compensated by a lower risk of relapse.

HLA matching affects clinical outcome of adult patients undergoing haematopoietic SCT from unrelated donors: a study from the Gruppo Italiano Trapianto di Midollo Osseo and Italian Bone Marrow Donor Registry

The importance of HLA donor–recipient matching in unrelated haematopoietic SCT (HSCT) is the subject of debate. In this retrospective study, we analyzed 805 adult patients from the Italian Registry receiving HSCT for a haematological malignancy from January 1999 to June 2006 and correlated the degree of HLA matching with transplant outcome. All patient–donor pairs had high-resolution typing at HLA-A, -B, -C, -DRB1 and -DQB1. There was a significantly higher risk of overall mortality, non-relapse mortality, graft failure and acute GVHD (aGVHD) for patients receiving HSCT from an unrelated donor with one or more low- or high-resolution mismatch/es (Mm/s). When only a single HLA Mm is present (9/10 matched pairs), mortality risk is higher than among 10/10 matched pairs in patients transplanted with acute leukaemia in the first CR (‘early’ patients) but not in the other patients (advanced patients): HR=1.69, 95% CI=0.94–3.02, P=0.08; HR=1.03, 95% CI=0.80–1.32, P=0.82, for early and advanced patients, respectively. These results confirm that the advantage of a 10/10 match has a greater effect in early patients, thus suggesting that a 9/10 matched donor can be chosen in patients with advanced disease lacking a rapidly available 10/10 matched one.

The intra-bone marrow injection of cord blood cells extends the possibility of transplantation to the majority of patients with malignant hematopoietic diseases

Cord blood transplant (CBT) in adult patients is scarcely utilized because of the risk of graft failure or very delayed platelet recovery. To improve the capacity and the speed to engraft, we have developed an intra-bone (IB) cord blood transplant technique. 75 patients with hematological malignancies, categorized by disease phase as early (18%), intermediate (20%) and advanced (62%), were transplanted. The median cell dose (TNC) infused was: 2.6 (1.35-5.4)×10(7)/kg; the HLA disparity was: 12 cases=5/6, 62 cases=4/6 and 1 case=3/6 matched antigens. 72/75 patients engrafted (96%); median day of recovery of neutrophils (PMN) >500×10(9)/L and platelets (PLT) >20 000×10(9)/L was: 23 (14-44) and 35 (16-70) days respectively. The outcomes at 2 years according to Kaplan-Meier are: OS=46%±5; RI=18%±2; NRM=39%±5. Acute GVHD incidence/severity was: grade 0-I=64%, II=14%, III-IV=0%. The incidence of Chronic GVHD was globally low but in 3 cases was very severe. Intra-bone CBT is associated with high rate of engraftment, early and robust platelet recovery, low incidence of acute GVHD. A very promising aspect is that the relapse rate is low considering the advanced phase of the disease in two/thirds of patients. A suitable CBU was found for nearly every patient searching for a CBU. Therefore, IB CBT extends the possibility to transplant any patient for whom this approach represents the sole possibility of long-term survival.

Impact of marrow unrelated donor search duration on outcome of children with acute lymphoblastic leukemia in second remission

Summary:We analyzed the outcome of 167 consecutive children with second CR acute lymphoblastic leukemia (ALL), for whom an unrelated donor (UD) search was activated between 1989 and 1998 at a median time of 2 months after relapse. A suitable donor was identified for 70 patients at 1 year and 6.5 months before and after 1995 from search activation, respectively; a further leukemia relapse occurred during the search in 94 children at a median of 4 months after search activation, 36 of whom underwent UD (14) or other types of transplant (22), beyond second CR, while 58 died of progressive disease. Of 73 patients not experiencing a second relapse, 64 underwent UD (46) or other types of transplant (18), while nine proceeded with chemotherapy, and only four of them survived. The 3-year disease-free survival (DFS) from second CR for the 167 patients is 15.1%, whereas 3-year DFS after transplant for the 60 UD and 40 alternative donor transplanted children is 31.6 and 25.4%, respectively. In conclusion, a further relapse is the main factor adversely affecting outcome of children with second CR ALL. Thus, for these patients, the search should be activated early after relapse and either a UD or an alternative transplant should be performed as early as possible.

The CIBMTR score predicts survival of AML patients undergoing allogeneic transplantation with active disease after a myeloablative or reduced intensity conditioning: a retrospective analysis of the Gruppo Italiano Trapianto Di Midollo Osseo

The CIBMTR score predicts survival of AML patients undergoing allogeneic transplantation with active disease after a myeloablative or reduced intensity conditioning: a retrospective analysis of the Gruppo Italiano Trapianto Di Midollo Osseo

Estimation of human leukocyte antigen class I and class II high-resolution allele and haplotype frequencies in the Italian population and comparison with other European populations

The high-resolution (HR) allele and haplotype frequencies of class I and II human leukocyte antigen (HLA) system were determined in the Italian population from a sample of donors recruited in the Italian Bone Marrow Donor Registry (IBMDR). This study analyzed the HLA-A, -B, -C, -DRB1, and -DQB1 loci. Two different samples were used: donors HR typed at least for one allele, usually when selected for donor-recipient matching (respectively: 3596, 7591, 4715, 57345, and 8196), to make a list of the observed alleles and determine the relative frequencies of the alleles in each class of the corresponding antigen; donors HR randomly typed for both the alleles (respectively: 975, 1643, 1569, 22114, and 2087) to estimate the allele and haplotype frequencies, and two loci linkage disequilibrium. The number of alleles showing a frequency >1% on the total number of observed alleles are 18/75 HLA-A, 28/142 -B, 17/57 -C, 23/154 -DRB1, and 13/31 -DQB1. In each locus they account for more than 88% of the total cumulative frequencies. The most frequent alleles are A*02: 01, B*35: 01, C*04:01, DRB1*07:01, DQB1*03:01. The most frequent five-locus haplotype in the 338 donors randomly typed is A*01: 01-C*07:01-B*08: 01-DRB1*03:01-DQB1*02:01. The genetic comparison of the Italian population with 16 European populations shows a south-north gradient.

Definitions of histocompatibility typing terms

Histocompatibility testing for stem cell and solid organ transplantation has become increasingly complex as newly discovered HLA alleles are described. HLA typing assignments reported by laboratories are used by physicians and donor registries for matching donors and recipients. To communicate effectively, a common language for histocompatibility terms should be established. In early 2010, representatives from Clinical, Registry, and Histocompatibility organizations joined together as the Harmonization of Histocompatibility Typing Terms Working Group to define a consensual language for laboratories, physicians, and registries to communicate histocompatibility typing information. The Working Group defined terms for HLA typing resolution, HLA matching, and a format for reporting HLA assignments. In addition, definitions of verification typing and extended typing were addressed. The original draft of the Definitions of Histocompatibility Typing Terms was disseminated to colleagues from each organization to gain feedback and create a collaborative document. Commentary gathered during this 90-day review period were discussed and implemented for preparation of this report. Histocompatibility testing continues to evolve; thus, the definitions agreed on today probably will require refinement and perhaps additional terminology in the future.

Chronic GVHD is associated with inferior relapse risk irrespective of stem cell source among patients receiving transplantation from unrelated donors

Chronic GVHD (cGVHD) has been associated with reduced risk of relapse after allo-SCT for onco-hematological disease due to a graft-vs-malignancy effect. Here we retrospectively analyzed a series of 802 adult patients transplanted from unrelated donors and found that cGVHD was associated with significantly lower relapse and that the limited form was associated with a survival advantage: hazard ratio for OS=0.63 (0.46–0.87); P=0.004; this was due to combination of relapse reduction and similar non-relapse mortality with respect to patients without cGVHD. Importantly, the graft-vs-malignancy effect observed here did not differ when PBSC or BM were used as stem cell source, thus suggesting that the protective effect of limited cGVHD is similar after PBSC- or BM-based transplantation. These findings could have practical implications and suggest no qualitative difference between cGVHD occurring after transplantation performed with different stem cell sources.