Transplantation strategies for the management of patients with myelodysplastic syndromes.

Allogeneic stem cell transplantation (SCT) is the only therapeutic modality at present that may be delivered with curative intent in patients with myelodysplastic syndromes (MDS). Allogeneic CST replaces recipient dysplastic hemopoiesis with healthy donor haemopoiesis and immune system with an attendant graft-versus-leukemia (GvL) effect. Its applicability, however, is limited by the age of MDS patients, high rates of transplant-related mortality (TRM) and availability of a suitable HLA-matched donor. Results from several large centres indicated 3-year overall survival (OS) rates of 20-45%, which are almost equal with the results obtained by intensive chemotherapy alone. Failure was due primarily to TRM in patients with low-risk MDS and to disease recurrence in patients with high-risk MDS. Allogeneic SCT from matched unrelated donors produce poorer results than matched related siblings' transplantations. In an attempt to reduce TRM and deliver allogeneic SCT in a greater subgroup of MDS patients, many researchers used reduced-intensity allografts (RIC or "mini"-allograft) for MDS. Although differences in patient populations, preparative regimens, and graft-versus-host disease (GvHD) prophylaxis, as well as donor source (related vs. unrelated) have to be considered, OS of up to 40% at 3 years and disease-free survival (DFS) rates of almost 35% at 3 years have been reported in selected centres. However, randomized prospective studies are needed to further address the optimal choice of transplant conditioning intensity in MDS. Autologous SCT has been extremely investigated in MDS. It is limited to patients who have achieved a complete remission (CR), can be harvested, and are candidates for the procedure. Autologous SCT after successful induction chemotherapy may increase the proportion of long-term survivors, thus improving CR duration in some patients with MDS, particularly in younger patients in remission. Results for older patients are unsatisfactory. The relapse rate is up to 75%, with a 2-year probability of DFS of only 25% for patients 40-60 years of age. Therefore, there is very limited enthusiasm for the future of autologous SCT in the management of MDS patients.

FLT3 overexpression in acute promyelocytic leukemia patients without detectable FLT3-ITD or codon 835-836 mutations: a pilot study.

BACKGROUND: Activating mutations of the FLT3 receptor tyrosine kinase are common in acute promyelocytic leukemia (APL) but have uncertain prognostic significance. Information regarding FLT3 expression levels in APL without FLT3 mutations is lacking. MATERIALS AND METHODS: Using RT-PCR, mutation analysis of the FLT3 gene, regarding internal tandem duplications (ITDs) and codon 835-836 point mutations, was performed and real-time PCR was carried out to determine the level of FLT3 expression in 11 APL patients at diagnosis and 5 in haematological remission with molecularly detectable disease. RESULTS: High levels of FLT3 transcript, at least a 10-fold increase compared to the normal controls, were found at diagnosis in all 3 mutated cases and in 2 patients without detectable FLT3 mutations. CONCLUSION: FLT3 overexpression can be documented in patients without FLT3 mutations. These patients might benefit from treatment using specific FLT3 tyrosine kinase inhibitors. Larger studies are needed to evaluate the clinical and biological significance of FLT3 overexpression in the absence of FLT3 mutations.

alpha Interferon treatment of essential thrombocythaemia and other myeloproliferative disorders with excessive thrombocytosis.

The effect of recombinant interferon alfa-2b on platelet count, thrombocytosis-associated symptoms and marrow fibrosis was studied in 18 patients with myeloproliferative diseases and associated thrombocytosis (nine with essential thrombocythaemia, three with polycythaemia vera, three with myelofibrosis and three with chronic myelogenous leukaemia). A reduction of the platelet count below 600 x 10(9)/L was achieved in 94%, and below 400 x 10(9)/L in 77% of the patients within 8 to 330 days of treatment. The selective thrombocytosis-reducing effect of alpha interferon was maintained for long periods of time in most patients without serious side effects. Thrombocytosis-associated symptoms were relieved once the number of platelets was reduced to near normal levels. Marrow reticulin content was found to be reduced after treatment in two of the seven patients studied. Side effects of alpha interferon were flu-like symptoms, which usually subsided within 7 days of treatment.

Clinical and immunological restoration in patients with AIDS after marrow transplantation, using lymphocyte transfusions from the marrow donor.

The diagnosis of transfusion-associated acquired immunodeficiency syndrome (AIDS) was made in 2 patients who developed delayed opportunistic infections and severe cytopenias--56 months for the former (patient 1) and 22 months for the latter, (patient 2) following bone marrow transplantation (BMT) for aplastic anemia. In the third case, grafting for acute leukemia (patient 3) (HIV) infection was probably responsible for the failure of hematological and immunological reconstitution 8 months after allogeneic BMT. Each patient received 6 lymphocyte transfusions from the marrow donor for 3 weeks, combined with a 3-month course of low-dose recombinant alpha interferon. This treatment was followed by recombinant gamma interferon for 3 months. We showed that these 3 patients could resume a normal life for 9 months, at least, and that hematological restoration was observed. Our treatment succeeded in correcting the defect of proliferative response to Candida and the impairment of gamma interferon generation for 4 months in one patient and for more than 12 months in the other two recipients. Nevertheless T4 lymphocyte levels increased only slightly and HIV can still be isolated from the patients' blood. At the time of writing, patients 1 and 3 remain in good health with a partial immunological restoration while patient 2 has died of neurological impairment 2 years after the AIDS diagnosis. Although we cannot generalize this successful therapeutic approach to all patients with AIDS, the results may provide an interesting model of the potential effect of lymphocyte transfusions and the role of interferon therapy.

Legionnaires' disease after bone marrow transplantation.

Four patients developed legionnaires' disease after bone marrow transplantation. Two cases occurred early after transplant and were considered as part of a hospital epidemic due to contamination of water supply. The other two cases were considered to be sporadic because they occurred 3-4 weeks after hospital discharge. The outcome was good in two patients. In the third patient, recurrent disease was probably due to acquired resistance to macrolides, and complete cure was achieved after treatment with pefloxacin and rifampicin. The fourth patient died of overwhelming infection despite early treatment with erythromycin and pefloxacin. During the same period we treated 14 patients with pefloxacin for prevention of bacterial infection, of whom none developed Legionella pneumophila infection, while three of the patients reported here were in a group of 11 patients who received only oral non-absorbable antibiotics for gut decontamination. The fourth patient in this report was receiving no antibiotics. Thus pefloxacin seems to be effective as prophylaxis against L. pneumophila infection. When the hospital water supply was heated to 60 degrees C and chlorinated, the nosocomial cases in the hospital completely disappeared.

'Fetal' erythropoiesis following bone marrow transplantation as estimated by the number of F cells in the peripheral blood.

The aim of this study was to define factor(s) influencing fetal erythropoiesis following bone marrow transplantation. Thirty-one transplanted patients (14 males, 17 females) were studied. The underlying diseases were chronic myelogenous leukaemia (CML, 18 patients), acute myeloblastic leukaemia (AML, 7 patients) and acute lymphoblastic leukaemia (ALL, 6 patients). Reticulocyte and peripheral F cell estimation was carried out in donors and patients before transplantation and repeatedly during recovery. For F cell estimation, an indirect immunofluorescence assay was utilized. A significant increase above pre-BMT values in the percentage of F cells was observed in all patients from days 11 to 40 after transplantation. The increase of F cells on days 15, 18, 25, 32, 40 and 50 after transplantation was statistically significant in 14 patients who had shown an increase of F cells following chemotherapy (high responders) compared with the remaining 17 patients who did not respond so significantly. This finding supports the influence of the host bone marrow micro environment. The nature of the mechanisms operating remains to determined.

Detection of CD55- and/or CD59-deficient red cell populations in patients with lymphoproliferative syndromes.

INTRODUCTION: Paroxysmal nocturnal hemoglobinuria is an acquired clonal stem cell disorder characterized by the decrease or absence of glycosylphosphatidylinositol-anchored molecules from the surface of the affected cells, such as CD55 and CD59, resulting in chronic intravascular hemolysis, cytopenia and increased tendency to thrombosis. PNH-phenotype has been described in various hematological disorders, mainly in aplastic anemia and myelodysplastic syndromes, while it has been reported that complete deficiency of CD55 and CD59 has also been found in patients with lymphoproliferative syndromes, like non-Hodgkin's lymphomas. MATERIALS AND METHODS: The presence of CD55- and/or CD59-defective red cell populations was evaluated in 217 patients with lymphoproliferative syndromes. The study population included 87 patients with NHL, 55 with HD, 49 with CLL, 22 with ALL and four with hairy cell leukemia. One hundred and twenty-one healthy blood donors and seven patients with PNH were also studied as control groups. The sephacryl gel microtyping system was performed for the detection of CD55- and CD59-deficient red cell populations. Ham and sucrose lysis tests were also performed in all samples with CD55 or CD59 negative populations. RESULTS: Red cell populations deficient in both CD55 and CD59 molecules were detected in 9.2% of patients with lymphoproliferative syndromes (more often in ALL and nodular sclerosis type of HD) and in all PNH patients. CD55-deficient red cell populations were found in 8.7% of LPS patients (especially in low grade B-cell NHL), while CD59-deficient populations were found in only two patients with low grade B-cell NHL. CONCLUSION: These data indicate a possible association between paroxysmal nocturnal hemoglobinuria phenotype and lymphoproliferative syndromes, while further investigation is necessary to work out the mechanisms and the significance of the existence of this phenotype in these patients.

Acute promyelocytic leukemia relapsing into FAB-M2 acute myeloid leukemia with trisomy 8.

Acute promyelocytic leukemia was diagnosed in a 48-year-old man; the karyotype was normal, whereas reverse transcriptase polymerase chain reaction (RT-PCR) analysis identified PML/RAR alpha chimeric transcripts of the bcr3 type. Rather unexpectedly, the patient did not respond to alltrans retinoic acid administration; he attained complete remission with conventional chemotherapy and became PML/RAR alpha negative. Two years later, while PML/RAR alpha negative on RT-PCR, he presented with thrombocytopenia. Bone marrow examination was compatible with myelodysplasia of the RAEB type; the karyotype was normal. Then, after 10 months, he developed overt acute myeloid leukemia with PML/RAR alpha negative, French-American-British M2 blasts; karyotypic analysis revealed mosaicism for trisomy 8.

Trisomy 11 with loss of the Y chromosome and trisomy 13 in a case of de novo acute myeloid leukemia.

We report a man with de novo acute myeloid leukemia (M4 of the FAB classification) bearing two abnormal clones in the bone marrow cells. The clones showed trisomy 11 with loss of the Y chromosome and trisomy 13, respectively.

Cytogenetic analysis and RAS mutations in primary myelodysplastic syndromes.

Cytogenetic analysis was performed in 60 patients with primary myelodysplastic syndromes--diagnosed, treated, and followed in our department. In 41 cases, the presence of the NRAS mutation was also evaluated. The aim of this study was to evaluate the prognostic value of chromosomal abnormalities and NRAS mutation. The median age of the patients was 67 years (18-88 years), and the French-American-British classification was as follows: refractory anemia 26, refractory anemia with ring sideroblasts 4, refractory anemia with excess of blast cells 15, refractory anemia with excess of blast cells in transformation 3, and chronic myelomonocytic leukemia 12. Survival analysis was performed for the patients with a normal (n = 35), an abnormal (n = 25) karyotype and with a single (n = 15) or multiple (n = 10) cytogenetic abnormalities. Abnormal karyotypes were detected in 25 of the 60 patients (41.6%). Fifteen of these patients had a single and 10 had two or more lesions. The median survival of the patients with a normal (33.1 months) and with an abnormal (36.5 months) karyotype was not significantly different. Patients with multiple lesions had a reduced median survival compared with patients with single anomalies (19.2 versus 39.7 months, p = 0.5). Patients with an abnormal karyotype progressed to acute leukemia more frequently compared with patients without lesions (36 versus 28.6%, p = 0.5). NRAS mutation was detected in 2 of 10 CMMoL patients studied and in none of the 31 patients with other types of myelodysplastic syndrome. Marrow blasts more than 10% significantly affected survival.