Biomedical subjects

F Frassoni

Publications and source records attributed to F Frassoni.

At least 37 records · Page 2Linked to original sources

PubMed2000

The dismal outcome in patients with acute leukaemia who relapse after an autograft is improved if a second autograft or a matched allograft is performed. Acute Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT).

All patients receiving autografts for acute leukaemia in remission between 1 January 1981 and 31 December 1996 and reported to the European Group for Blood and Marrow Transplantation and had a relapse, were included. The patients underwent an allograft (n = 90, group A), were treated with chemotherapy (n = 2584, group B) or received a second autograft (n = 74, group C). The 2-year survival after relapse was 32 +/- 5%, 11 +/- 1% and 42 +/- 6% in groups A, B and C, respectively. In group A, those with an HLA-A, -B and -DR compatible related or unrelated donor had a 2-year survival of 37 +/- 7% compared to 13 +/- 8% for those receiving a graft from an HLA mismatched donor (n = 20). The following factors were associated with better survival in multivariate analyses: an interval from first autograft to relapse >5 months (P < 0.00001), a first autograft performed later than 1991 (P < 0.00001), patient age below 26 years (median, P < 0.002), group B vs HLA mismatches from group A (P = 0.002), group C vs group B (P < 0.005), patients who were not treated with total body irradiation at first autograft (P < 0.02) and patients in first remission at first autograft (P = 0.02). To conclude, the poor outcome in these patients was improved if a second autograft was feasible (P < 0.005), or if an HLA-matched allograft was performed (NS). Bone Marrow Transplantation (2000).

Acute Disease↗

PubMed2000

Phenotypic and functional analysis of the HLA-class I-specific inhibitory receptors of natural killer cells isolated from peripheral blood of patients undergoing bone marrow transplantation from matched unrelated donors.

INTRODUCTION: Limited information is available on the natural killer cell reconstitution after bone marrow transplantation and on the possible role of these cells in graft-versus-host-disease. MATERIALS AND METHODS: Blood samples were collected at different time intervals after transplantation. Lymphocytes were analyzed for informative markers by immunocytofluorimetric analysis. Natural killer cells derived from patients undergoing matched unrelated donor transplant were cloned by limiting dilution in the presence of phytohemoagglutinin and IL2. The natural killer cell clones were analyzed for cytolytic activity. RESULTS: In the nine patients analyzed undergoing transplantation from sibling donors, the majority of peripheral blood lymphocytes during the first 80 d after BMT were represented by T lymphocytes, while in the 15 patients undergoing matched unrelated donor transplant natural killer cells consistently outnumbered T lymphocytes. During the early phases after transplantation, most CD56+CD3- natural killer cells did not express CD16 which was expressed at later intervals. Analysis of the inhibitory receptors specific for HLA-class I molecules showed that CD94/NKG2A, specific for HLA-E, unlike normal donors, was expressed by all natural killer cells including the early appearing CD16-negative ones. Killer inhibitory receptors of the Ig superfamily were expressed late and in low percentages after transplantation and were always coexpressed with CD94/NKG2A. Natural killer-cell clones efficiently lysed the HLA-class I-negative cell lines K562 and 721-221. Natural killer-cell populations or clones isolated from patients with graft-versus-host-disease, failed to lyse donor or recipient derived phytohemoagglutinin-induced lymphoblasts. CONCLUSION: Our analysis shows that (1) recipients of matched unrelated donors transplants exhibit a high proportion of NK cells (2) all NK cells express CD94/NKG2A while the HLA-class I-specific inhibitory receptors of Ig superfamily appear at later stages and (3) donor NK cells do not lysed donor or recipient target cells.

Adolescent↗

PubMed2000

The combined effect of total body irradiation (TBI) and cyclosporin A (CyA) on the risk of relapse in patients with acute myeloid leukaemia undergoing allogeneic bone marrow transplantation.

One hundred and fifty acute myeloid leukaemia (AML) patients in first remission received an allogeneic bone marrow transplant (BMT), after conditioning with cyclophosphamide 120 mg/kg and total body irradiation (TBI) 3.3 Gy x 3 (total nominal dose 9.9). The received dose, as recorded by thermoluminescent dosimeters, ranged between 7. 83 and 12.25 Gy. Patients who received TBI < 9.9 Gy (n = 34) had a significantly higher relapse rate when compared with patients receiving >/= 9.9 Gy (n = 116) (43% vs. 19%; P = 0.002). Graft versus host disease (GvHD) prophylaxis consisted of cyclosporin A (CyA) with or without methotrexate (MTX). The dose of CyA was either 1 or 5 mg/kg/day i.v. from day -1 to + 20, then 10 mg/kg/day orally until day + 365. Patients receiving 5 mg/kg CyA (n = 40) had a higher risk of relapse (49% vs. 15%; P = 0.0001). Thus, low-dose TBI (< 9.9 Gy) and high-dose CyA (5 mg/kg) were significant predictors of leukaemia relapse. Patients were then divided into three groups: those who had both negative predictors (< 9.9 Gy TBI and 5 mg/kg CyA; n = 26); those who had only one (either < 9.9 Gy TBI or 5 mg/kg CyA; n = 22); and those who had neither (>/= 9.9 Gy TBI and 1 mg/kg CyA; n = 102). The three groups were comparable for FAB subtype, interval diagnosis transplant and age. The 5-year actuarial relapse rate for these three groups of patients was 49%, 41% and 15%, with no difference between the first two and a significant difference when compared with the latter (P < 0.01). These data indicate that acute myeloid leukaemia can be cured with allogeneic bone marrow transplantation given an intensive conditioning regimen and low-dose immunosuppression post-graft. Either alone is insufficient to produce long-term disease-free survival. These results may be relevant for programmes of reduced intensity conditioning designed for patients with acute leukaemia.

Acute Disease↗

PubMed2000

Quality of life in 244 recipients of allogeneic bone marrow transplantation.

The number of long-term survivors after allogeneic bone marrow transplantation (BMT) has been increasing over the past years, and quality of life (QOL) has become an important end-point. We studied 244 patients undergoing an allogeneic BMT to identify factors and events influencing psychosocial outcome. Patients enrolled received the Psychosocial Adjustment to Illness Scale (PAIS) questionnaire assessing psychological and social adjustment to chronic illness or its sequelae. Eighty-two per cent of patients had a haematological disease. The median age was 28 years at BMT, and the median follow-up was 61 months. The median overall PAIS score for all patients was 56 (range 22-76): 25% (n = 61) of patients were considered to have a good QOL (</= 25 percentile score); 44% (n = 108) of patients had an intermediate QOL (26-75 percentile score) and 31% (n = 75) had a poor QOL (> 75 percentile score). Factors associated with a poor QOL in multivariate analysis were: patients' age at BMT (> 25 years, P < 0.01); presence of long-term sequelae (P < 0.01); chronic graft-versus-host disease (GVHD) (P < 0.05); and a short interval from BMT (< 5 years; P < 0.05). The QOL improved with time: 12% of patients reported a good QOL within 5 years compared with 38% after this time point and, conversely, 38% reported a poor QOL within 5 years compared with 24% after this time point (P < 0. 0001). Older patients had significantly poorer QOL compared with younger patients (< or = 25 years; P = 0.01). Females had significantly poorer scores when compared with males in the sexual (P < 0.0001) and psychological domains (P = 0.001). The data suggest that (i) one-third of patients undergoing allogeneic BMT report a poor QOL; (ii) factors associated with poor QOL are older age, presence of long-term sequelae, chronic GVHD and short follow-up; (iii) QOL is superior in long-term survivors; and (iv) BMT affects different aspects of life in males and females. A longitudinal study is ongoing to prove the effect of time on quality of life.

Adolescent↗

PubMed2000

Reduced intensity thiotepa-cyclophosphamide conditioning for allogeneic haemopoietic stem cell transplants (HSCT) in patients up to 60 years of age.

UNLABELLED: Transplant-related mortality (TRM) remains a major problem in older patients undergoing allogeneic haemopoietic stem cell transplants (HSCTs). We have therefore explored a less intensive conditioning in 33 patients with a median age of 52 years (range 43-60) transplanted from human leucocyte antigen (HLA)-identical siblings. The underlying disease was chronic myeloid leukaemia (n = 15), acute myeloid leukaemia (n = 6), myelodysplasia (n = 7) or a chronic lymphoproliferative disorder (n = 5); 15 patients (45%) had advanced disease. The regimen consisted of thiotepa (THIO; 10 mg/kg) on day -5 and cyclophosphamide (CY; 50 mg/kg) on days -3 and -2 (total dose 100 mg/kg). The source was bone marrow (BM) (n = 17) or granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood (PB) (n = 16), which were infused without manipulation. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin A (CyA) and a short course of methotrexate. Mean time to achieve a neutrophil count of 0.5 x 109/l was 17 d (range 11-23) and full donor chimaerism was detected in 79% of patients by day 100. Acute GVHD grade III or IV occurred in 3% of patients. Chronic GVHD was seen in 45% of patients, with a significant difference for PB (69%) compared with BM transplants (23%) (P = 0.009). For BM grafts, the actuarial 2-year TRM was 6%, the relapse 56% and survival 87%; for PB grafts, these figures were, respectively, 27%, 33% and 68%. Twenty-five patients are alive at a median follow-up of 762 d (range 216-1615) and 20 patients (60%) remain free of disease. Thirteen patients (39%) received donor lymphocyte infusion (DLI) either for persisting or relapsing disease and six patients had complete remission. IN CONCLUSION: (i) patients up to the age of 60 years can be allografted with reduced intensity conditioning; (ii) the procedure was associated with a low transplant-related mortality, particularly for bone marrow grafts, because of a lower risk of chronic GVHD; and (iii) DLI were required after transplant in half the patients for persisting disease or relapse.

Adult↗

PubMed2000

No impact of high-dose cytarabine on the outcome of patients transplanted for acute myeloblastic leukaemia in first remission. Acute Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT).

High-dose cytarabine is currently used in combination with anthracycline in the treatment of acute myeloblastic leukaemia (AML). Moreover, high-dose cytarabine has been reported to produce long-term disease-free survival in a proportion of patients, especially in certain subtypes of AML. However, it remains unknown whether the outcome of patients undergoing allogeneic or autologous stem cell transplantation is influenced by previous treatment with high-dose cytarabine. To this end, 1672 patients with AML in first remission who were reported to the Acute Leukaemia Working Party registry of the European Group for Blood and Marrow Transplantation (EBMT) and who were transplanted between 1980 and 1995 were analysed according to the dose intensity of cytarabine given at induction and/or consolidation. Autologous stem cell transplantation (ABMT) was performed in 846 patients and allogeneic bone marrow transplantation (BMT) in 826 patients. This study shows that the dose of cytarabine (Ara-C) given at induction and/or consolidation did not influence the relapse incidence in patients subsequently allografted or autografted. In addition, it did not give any advantage in terms of overall outcome. Therefore, high-dose (HD) Ara-C may not be needed for patients who have a planned stem cell transplantation (SCT) as post-remission therapy. Nevertheless, HD Ara-C may be utilized in certain subtypes of AML that are believed to be curable by chemotherapy alone.

Adolescent↗

PubMed2000

Feasibility and recent improvement of autologous stem cell transplantation for acute myelocytic leukaemia in patients over 60 years of age: importance of the source of stem cells.

A total of 193 patients with acute myelocytic leukaemia (AML) [147 in first complete remission (CR1)], ranging from 60 years to 75 years of age (median 63 years), were autografted between January 1984 and December 1998. The source of stem cells was peripheral blood (PB) in 128 patients, bone marrow in 51 patients and a combination of both in 14 patients. Total body irradiation (TBI) was used in 34 cases. Ninety-seven per cent of patients had successful engraftment of neutrophils on day 15 (range days 7-71) and of platelets on day 30 (range days 9-894). In patients autografted in CR1, the transplant-related mortality (TRM) was 15 +/- 4%, the relapse incidence (RI) was 58 +/- 5%, the leukaemia-free survival (LFS) was 36 +/- 5% and the overall survival was 47 +/- 5% at 3 years. The source and dose of stem cells were studied in particular; in patients transplanted in CR1, the RI was 44 +/- 11% in those receiving marrow compared with 63 +/- 6% in those receiving PB (P = 0.04). Patients autografted in CR1 who received higher granulocyte-macrophage colony-forming units (CFU-GM) doses (above the median) had a lower RI (47 +/- 11% vs. 79 +/- 9%, P = 0.009). There was a significant improvement in patients transplanted after March 1996; for those in CR1, the RI was 41 +/- 8% vs. 65 +/- 6% (P = 0.01), the LFS was 53 +/- 8% vs. 28 +/- 5% (P = 0.01) and the overall survival was 72 +/- 7% vs. 36 +/- 6% (P = 0.02). By multivariate analyses, significant factors for the outcome were the date of transplant with recent improvement and the source of stem cells, with a lower RI for marrow. Autologous stem cell transplantation (ASCT) is a potential therapeutic approach in patients with AML over 60 years of age; results have improved recently.

Aged↗

PubMed2000

Is there a graft-versus-leukaemia effect in the absence of graft-versus-host disease in patients undergoing bone marrow transplantation for acute leukaemia?

During a 13-year period, 5200 autografts, 1039 HLA-identical sibling transplants without acute or chronic graft-vs.-host disease (GVHD) and 67 twins were reported to the European Group for Blood and Marrow Transplantation EBMT. Follow-up time was a median of 32 months. Diagnoses were acute myeloid leukaemia (AML, 4521) and acute lymphoblastic leukaemia (ALL, 1785) in first complete remission. The probability of relapse at 5 years was 51 +/- 1% in the autografts, 45 +/- 8% in the twins and 34 +/- 2% among the HLA-identical siblings (auto vs. sibs, P < 0.0001). In multivariate analyses, the following factors were significantly associated with an increased risk of relapse: ALL vs. AML M3 [relapse rate (RR) 2.29, P < 0.0001], AML non-M3 vs. AML M3 (RR 1.8, P < 0.0001), autograft vs. sibling transplant (RR 1.76, P < 0.0001), interval diagnosis to transplantation < 261 d (RR 1.45, P < 0.001) and other conditioning vs. total body irradiation (RR 1.16, P = 0.001). Transplant-related mortality was the same in the three groups at approximately 10% at 2 years. Five-year leukaemia-free survival was 42 +/- 1% in the autografts, 44 +/- 8% in the twins and 58 +/- 2% among the siblings (auto vs. sibs, P < 0.0001). The factors significant for relapse were also significant in multivariate analyses for leukaemia-free survival. In addition, children had a significantly better leukaemia-free survival than adults (RR 0.82, P < 0.0001). Recipients of bone marrow from HLA-identical siblings without GVHD had a lower risk of relapse and a better leukaemia-free survival than recipients of autografts. This may be as a result of a graft-vs.-leukaemia effect in the absence of GVHD.

Acute Disease↗

PubMed2000

Bone marrow or peripheral blood as a source of stem cells for allogeneic transplants.

Peripheral blood stem cell transplants are being increasingly used in the allogeneic setting and are often preferred to the conventional bone marrow source. The aim of this report is to review available data on peripheral blood versus bone marrow hematopoietic stem cell transplantation. The discussion is restricted to HLA-identical sibling transplants receiving unmanipulated grafts. This is because data with appropriate follow-up are available only for this type of comparison: we have preliminary data on the use of peripheral blood from unrelated donors, and on the use of T-cell depletion/CD34+ selection methods. The latter are evolving rapidly and it may be difficult to find a concurrent group of patients receiving T-cell-depleted or CD34-selected marrow. The results of retrospective and prospective studies are similar: hematologic and immune recovery are faster after peripheral blood grafts, acute graft-versus-host disease is comparable, whereas chronic graft-versus-host disease is increased in recipients of peripheral blood transplants. Transplant-related mortality is similar in the two groups, whereas disease recurrence is lower after peripheral blood grafts. The general opinion is that peripheral blood grafts are indicated for patients with advanced disease, whereas for patients with early-phase disease the two sources may give comparable results.

Bone Marrow Transplantation↗

PubMed2000

Issues in the manufacture and transplantation of genetically modified hematopoietic stem cells.

The advent of safe and practical means to correct, enhance or protect blood cells at the genetic level offers tantalizing therapeutic perspectives. At present, gene delivery using a replication-defective retrovirus is the most efficient method to stably transduce hematopoietic cells. The successful adaptation of retroviral infection to hematopoietic stem cells requires optimized transduction conditions that maximize gene transfer while preserving the cells' potential for engraftment and longterm hematopoiesis. The successful establishment of effective transduction protocols hinges on retrovirus biology as well as stem cell and transplantation biology. Interestingly, the genetic approach could permit novel strategies to promote host repopulation by transplanted stem cells. However, regulated and predictable expression of any transgene integrated at random chromosomal locations cannot be taken for granted. Investigation of the control of transgene expression and prevention of vector silencing will become increasingly important.

Animals↗

PubMed2000

Bone marrow transplantation for paroxysmal nocturnal hemoglobinuria.

BACKGROUND AND OBJECTIVE: Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal disease of the hemopoietic stem cell (HSC) characterized by intravascular hemolysis and increased risk of venous thrombosis. There are different therapeutic approaches for PNH which do not cure the disease, but can decrease its complications. Allogeneic bone marrow transplantation (BMT) may cure PNH. We reports here our experience of seven PNH patients who underwent allogeneic BMT. DESIGN AND METHODS: Between January 1991 and January 1999 seven patients with PNH, aged 23 to 37, were transplanted with unmanipulated bone marrow from HLA identical siblings. Median time from diagnosis to BMT was 2.5 years (range: 1-16). All patients were transfusion-dependent and had received various treatments before BMT: steroids, vitamins, cyclosporin A (CyA), growth factors. One patient had also been treated with anti-thymocyte globulin. One patient was HbsAg positive and one anti-HCV positive. At the time of BMT the median value of hemoglobin (Hb) was 9 g/dL (range 6.5-11), white blood cells 5&10(9)/L (range: 2.9-7.7), platelets 97&10(9)/L (range: 31-355), LDH: 2726 U/L. The conditioning regimen was cyclophosphamide (160 mg/kg) and busulfan (10-14 mg/kg), followed by unmanipulated bone marrow (median of 5&10(8) cells/kg) and CyA (+MTX in two patients) for prophylaxis of graft-versus-host disease (GvHD). RESULTS: All seven patients are alive, full chimeras, with complete hematologic recovery and no evidence of PNH, at a median follow up of 51 months post-BMT (6-103). Time to achieve a granulocyte count of 0.5&10(9)/L, platelets 30&10(9)/L and Hb 10 g/dL was respectively 16, 19 and 22 days. Acute GvHD was limited or mild in six patients, and severe in one. Chronic GvHD was extensive in two patients. INTERPRETATION AND CONCLUSIONS: This study confirms that HLA identical sibling BMT is an effective therapeutic option for PNH, also in the hemolytic phase of the disease: it also suggests that HBV and HCV infections are not an absolute contraindication.

Adult↗

PubMed1999

Autografting with philadelphia chromosome-negative mobilized hematopoietic progenitor cells in chronic myelogenous leukemia.

Intensive chemotherapy given in early chronic phase of chronic myelogenous leukemia (CML) has resulted in high numbers of circulating Philadelphia (Ph) chromosome-negative hematopoietic progenitor cells (HPC). We have autografted 30 consecutive patients with CML in chronic phase with HPC collected in this way to facilitate restoration of Ph-negative hematopoiesis in bone marrow after high-dose therapy. Hematopoietic recovery to greater than 0.5 x10(9)/L neutrophils and to greater than 25 x 10(9)/L platelets occurred in all patients, a median of 13 (range, 9 to 32) days and 16 (range, 6 to 106) days postautograft, respectively. Regenerating marrow cells were Ph-negative in 16 (53%) patients and greater than 66% Ph-negative in 10 (33%) patients. Twenty-eight patients are alive 6 to 76 months (median, 24 months) after autografting. Three patients have developed blast crisis from which 2 have died. Eight patients are in complete cytogenetic remission at a median of 20 (range, 6 to 44) months with a median ratio BCR-ABL/ABL of 0.002 (range, <0.001 to 0.01). Eight patients are in major cytogenetic remission at a median of 22 (range, 6 to 48) months. No patient died as a consequence of the treatment. All patients had some degree of stomatitis that was severe in 15 (50%) patients. Gastrointestinal and hepatic toxicities were observed in about one fourth of patients. Thus, autografting with Ph-negative mobilized HPC can result in prolonged restoration of Ph-negative hematopoiesis for some patients with CML; moreover, most autograft recipients report normal or near normal activity levels, suggesting that this procedure need not to be associated either with prolonged convalescence or with chronic debility.

Adult↗

PubMed1999

Total body irradiation correlates with chronic graft versus host disease and affects prognosis of patients with acute lymphoblastic leukemia receiving an HLA identical allogeneic bone marrow transplant.

PURPOSE: To investigate whether different procedure variables involved in the delivery of fractionated total body irradiation (TBI) impact on prognosis of patients affected by acute lymphoblastic leukemia (ALL) receiving allogeneic bone marrow transplant (BMT). METHODS AND MATERIALS: Ninety-three consecutive patients with ALL receiving a human leukocyte antigen (HLA) identical allogeneic BMT between 1 August 1983 and 30 September 1995 were conditioned with the same protocol consisting of cyclophosphamide and fractionated TBI. The planned total dose of TBI was 12 Gy (2 Gy, twice a day for 3 days). Along the 12-year period, variations in delivering TBI schedule occurred with regard to used radiation source, instantaneous dose rate, technical setting, and actual total dose received by the patient. We tested these different TBI variables as well as factors related to patient, state of disease, and transplant-induced disease to investigate their influence on transplant-related mortality, leukemia relapse, and survival. RESULTS: At median follow-up of 7 years (range 3-15 years) the probabilities of leukemia-free survival (LFS) and overall survival (OS) for the 93 patients were 60% and 41%, respectively. At univariate analysis, chronic graft versus host disease (cGvHd) (p = 0.0005), age (p = 0.01), and state of disease (p = 0.03) were factors affecting LFS whereas chronic GvHd (p = 0.0005), acute GvHd (p = 0.03), age (p = 0.0001), and GvHd prophylaxis (p = 0.01) were factors affecting overall survival. The occurrence of chronic GvHd was correlated with actually delivered TBI dose (p = 0.04). Combined stratification of prognostic factors showed that patients who received the planned total dose of TBI (12 Gy) and were affected by chronic GvHd had higher probabilities of LFS (p = 0.01) and OS (p = n.s.) than patients receiving less than 12 Gy and/or without occurrence of chronic GvHd. Moreover, TBI dose had a significant impact on LFS in patients transplanted in first remission (p = 0.05). At multivariate analysis, TBI dose was an independent factor affecting overall survival (p = 0.05) as well as chronic GvHd (p = 0.001) and age (p = 0.04). CONCLUSIONS: This retrospective analysis showed that different variables involved in TBI delivery may influence the occurrence of cGvHd and affect prognosis of patients with ALL receiving allogeneic BMT. The total dose of 12 Gy, administered in six fractions over 3 days, appears to be an effective and low toxic regimen for ALL patients transplanted in first remission.

Adolescent↗

PubMed1999

Allogeneic bone marrow transplant or second autograft in patients with acute leukemia who relapse after an autograft. Acute Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT).

Among 2752 patients with acute leukemia who had recurrent leukemia after autograft in remission and were reported to the EBMT, 94 underwent an allogeneic bone marrow transplant and 74 received a second autograft. Recipients of HLA-mismatched related or unrelated bone marrow had an increased transplant-related mortality (TRM, P = 0.017) and a decreased leukemia-free survival (LFS, P = 0.03), compared to recipients of HLA matched related or unrelated bone marrow. Outcome in recipients of HLA-compatible related or unrelated bone marrow was compared to those receiving a second autograft. TRM at 2 years was 51 +/- 8% in recipients of matched allografts and 26 +/- 6% following a 2nd autograft (P < 0.05). Two-year LFS was 27 +/- 7% and 35 +/- 6% in the two groups, respectively (NS). Multivariate analysis in these two groups showed that TRM was increased in patients who were in 2nd or later remission at 1st autograft (P < 0. 05) and allograft recipients (P < 0.05). Relapse was more common in patients with ALL (P < 0.001), above 25 years of age (P < 0.02), autograft performed later than 1991 (P < 0.05), and in second autografts (P < 0.05). LFS was decreased in patients >25 years of age (P < 0.01), if the interval from first autograft to relapse was 8 months or less (P < 0.01) and if TBI was used at first autograft (P < 0.05).

Adolescent↗

PubMed1999

Relapse after allogeneic BMT for chronic myeloid leukemia (CML) may be sustained by a small number of leukemic 'stem cells': a hypothesis.

'.the leukemic stem line is a small minority within the total cell mass;. when the leukemic stem line is not exceeding the normal stem cell numbers, its proliferation may still be under partial control.' LG Lajtha, Blood Cells 1981; 7: 45-62 We performed cytogenetic analysis on fresh bone marrow cells and on progenitor cell colonies in a patient who relapsed after allogeneic BMT for CML and was subsequently treated with donor lymphocyte infusions (DLI). Two Philadelphia-positive clones were identified at relapse. One clone displayed an additional chromosomal abnormality most likely induced by radio-chemotherapy and therefore arising in a single cell. This cell displays the characteristics of a stem cell, since it was able to support 20% of Ph-positive hemopoiesis for 5 months. If the progeny of a single Ph-positive stem cell account for 20% of hemopoiesis, a very low number of leukemic stem cells may sustain relapse after allogeneic BMT. This is in keeping with two observations: (1) at relapse, long-term culture initiating cells (LTC-IC) were all donor-derived and Ph-negative; (2) on average, the pace of the disease is very slow after relapse following allogeneic-BMT. Therefore, we hypothesize that a small number of leukemic stem cells may be involved in the initial events of relapse following BMT for CML.

Bone Marrow Transplantation↗

PubMed1999

Normal primitive haemopoietic progenitors are more frequent than their leukaemic counterpart in newly diagnosed patients with chronic myeloid leukaemia but rapidly decline with time.

We carried out studies to quantify Ph-negative progenitors both in steady state and during regeneration after chemotherapy and G-CSF in 23 newly diagnosed chronic myeloid leukaemia (CML) patients (group A) and in 14 individuals more than a year from diagnosis (nine in chronic and five in accelerated phase, group B). In steady-state bone marrow, Ph-negative long-term culture initiating cells (LTC-IC) and Ph-negative colony-forming-cells (CFC) were detected in 18/23 and 14/23 patients of group A versus 3/14 and 3/14 patients of group B (P<0.001 and P<0.02, respectively). The absolute number of mobilized Ph-negative progenitors was markedly higher in group A versus group B (P<0.02 for LTC-IC, P<0.003 for CFC). 12/16 newly diagnosed patients mobilized Ph-negative LTC-IC only and the yield was in the range of normal allogeneic donors. Overall the frequency of Ph-negative LTC-IC in the bone marrow predicted the yield of Ph-negative LTC-IC mobilized into peripheral blood (P<0.001). The bone marrow frequency of Ph-positive LTC-IC was considerably lower than the normal counterpart. Taken together, these findings suggest that normal progenitors are relatively well preserved in newly diagnosed CML patients, but tend to rapidly decline with time. This observation helps in the understanding of the pathogenesis of CML and has potential implications for autografting. The optimal time for a successful collection of Ph-negative circulating progenitors would appear to be soon after diagnosis.

Adult↗

PubMed1999

Coexistence of normal and clonal haemopoiesis in aplastic anaemia patients treated with immunosuppressive therapy.

Cytogenetic abnormalities and paroxysmal nocturnal haemoglobinuria (PNH) phenotype are frequent findings in aplastic anaemia patients treated with immunosuppressive therapy (IST). In this study we investigated whether the appearance of clonal haemopoiesis influences patient outcome and survival. 97 patients entered this study and were followed from the onset of the disease for a median follow-up (FU) of 53 months. 93% are alive, 56% achieved complete remission, 30% partial remission, both transfusion independent, and 14% did not respond. Three groups were identified: (A) patients without evidence of emerging clones (71/97); (B) patients who acquired chromosomal abnormalities (13/97); (C) patients who showed low expression of glycosyl phosphatidylinositol anchored proteins (GPI-AP) (PNH phenotype) at presentation or later (16/97). Three patients showed both PIG-AP deficiency and chromosomal abnormalities. The actuarial survival of patients without clonal haemopoiesis (n = 71) at 6 years was 95%, for patients with chromosomal abnormalities (n = 13), 88%, and for patients with PIG-AP deficiency (n = 16), 89%. There was no difference in the probability of becoming transfusion independent in the three groups (93%, 92% and 88% respectively). This study confirmed that a proportion of severe aplastic anaemia (SAA) patients exhibit clonal markers during the time after IST, often coexisting with cytogenetically or phenotypically normal haemopoiesis. There was no significant clinical impact of these abnormalities on transfusion independence and survival at the median follow-up of 4 years.

Adolescent↗

PubMed1998

Risk assessment for patients with chronic myeloid leukaemia before allogeneic blood or marrow transplantation. Chronic Leukemia Working Party of the European Group for Blood and Marrow Transplantation.

BACKGROUND: Transplantation of blood or bone-marrow stem cells is the treatment of choice for selected patients with chronic myeloid leukaemia (CML). Transplantation is used with increasing frequency and success, but remains associated with substantial risks of morbidity and mortality. Other treatments with satisfactory short-term outcome are available. For appropriate counselling of patients, a rapid and simple way to assess risk is needed. METHODS: Data from 3142 patients (1873 [60%] male, 1269 [40%] female; mean age 34 years, range <1-60 years) treated with allogeneic blood or marrow transplants for CML between 1989 and 1997, reported to the European Group for Blood and Marrow Transplantation (EBMT), were used to develop and test a simple risk score based on previously reported major pretransplant risk factors: histocompatibility, stage of disease at time of transplantation, age and sex of donor and recipient, and time from diagnosis to transplantation. We analysed probabilities of survival, leukaemia-free survival, transplant-related mortality, and relapse incidence with respect to these risk factors. FINDINGS: At the time of analysis, 1922 (61%) of the 3142 patients were alive-1567 (65%) of those with HLA-identical sibling donors and 417 (57%) of those with unrelated donors. 1682 (54%) were alive without relapse. 1220 (39%) patients had died, 1013 (83%) of transplant-related causes, 207 (17%) of relapse. 447 (14%) patients had relapsed. The final scoring system was highly predictive for leukaemia-free survival, survival and transplant-related mortality. Survival at 5 years was 72%, 70%, 62%, 48%, 40%, 18%, and 22% for patients with scores 0, 1, 2, 3, 4, 5, and 6, respectively. Risk of transplant-related mortality was 20%, 23%, 31%, 46%, 51%, 71%, and 73%. Data showed the same trends for HLA-identical sibling transplants and unrelated transplants for transplants done in 1989-93 and 1994-96. INTERPRETATION: Pretransplant risk factors are cumulative for individual patients with CML having blood or marrow transplantation. A simple system based on five main factors gives adequate risk assessment for counselling of patients and taking decisions.

Adolescent↗