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T Barbui

Publications and source records attributed to T Barbui.

At least 55 records · Page 3Linked to original sources

Clinical sensitivity to anthracyclines in PH/BCR+ acute lymphoblastic leukemia.

Translocation t(9;22) or Philadelphia chromosome (Ph)/BCR-ABL rearrangement positive acute lymphoblastic leukemia (Ph/BCR+ ALL) is associated with a very short survival of about one year in most patients. We analyzed long-term outcome of 76 adults with Ph/BCR+ ALL, in order to detect which factors were associated with longer survival. Modifiable prognostic factors included type of treatment, allogeneic marrow transplant (allo-BMT), and early anthracycline dose intensity (high = H/A, low = L/A); unmodifiable factors were age, gender, FAB morphology, phenotype, blast count, P190/210 transcript, hepatospleno-lymphadenopathy, LDH level. Median patient age was 43 years (range 15-71). Four favorable prognostic factors (FPF) were found associated with greater likelihood of complete remission (blast count < 50 x 10(9)/l, p = 0.08), longer remission duration (age < 50 years, p < 0.001; H/A, p < 0.05), and lower relapse rate (allo-BMT, p = 0.017). Age and anthracycline dose intensity exerted a synergistic prognostic effect. According to the cumulative incidence of FPF in each patient (FPF 0-1 = 29, 2-3 = 42, 4 = 5), the probability of survival increased from nil to 0.22 to 0.60 at 5 years (p < 0.005). Adult Ph/BCR+ ALL is relatively sensitive to anthracyclines, which therefore should be prescribed at full dosage to patients not eligible to allo-BMT or in the waiting list for unrelated donor transplantation.

Adolescent↗

Treatment of essential thrombocythemia with special emphasis on leukemogenic risk.

Acute leukemia and myelodysplastic syndromes are rare, but almost invariably fatal, evolutions of essential thrombocythemia (ET). Three major factors are associated with blastic transformation: cytogenetic abnormalities, myelofibrotic features, and the use of cytotoxic agents. Hematological malignancies have been reported in ET patients after treatment with alkylating agents, such as busulphan, as well as other cytoreductive drugs, such as hydroxyurea. Concerns about leukemogenicity have led some to suggest limiting the indications of these drugs to patients at higher risk of bleeding and thrombosis. Major risk factors for thrombosis are age above 60 years and a previous thrombotic event, whereas an increased bleeding tendency has been reported with platelet counts in excess of 1000-1500x10(9)/l. No myelosuppressive therapy is recommended for younger patients if they are asymptomatic or their platelet counts are below 1500x10(9)/l. The threshold of 1500x10(9)/l is controversial, however, and cytoreduction can be considered when platelets are above 1000x10(9)/l or in the presence of risk factors for cardiovascular disease. In the presence of thrombotic events or extreme thrombocytosis, young ET patients can be managed with cytoreductive agents theoretically devoid of leukemogenic risk, such as a-interferon or anagrelide. Nevertheless, the mutagenic risk of anagrelide has not been investigated in long-term follow-up studies, and the ultimate place of these 'new' drugs in the management of ET patients remains to be established in prospective and controlled clinical trials.

Antineoplastic Agents↗

Diagnosis, pathogenesis and treatment of the myeloproliferative disorders essential thrombocythemia, polycythemia vera and essential megakaryocytic granulocytic metaplasia and myelofibrosis.

According to strict clinical, hematological and morphological criteria, the Philadelphia (Ph) chromosome negative chronic myeloproliferative disorders essential thrombocythemia (ET), polycythemia vera (PV), and agnogenic myeloid (megakaryocytic/granulocytic) metaplasia (AMM) or idiopathic myelofibrosis (IMF) are three distinct disease entities with regard to clinical manifestations, natural history and outcome in terms of life expectancy. As clonality studies have clearly demonstrated that fibroblast proliferation in AMM, as well as in many other conditions such as advanced stages of Ph(+)-essential thrombocythemia, Ph(+)-granulocytic leukemia, and Ph(-)-polycythemia vera, is polyclonal indicating that myelofibrosis is secondary to the megakaryocytic granulocytic metaplasia in these various conditions, AMM is illogically labeled as IMF. As abnormal megakaryocytic granulocytic metaplasia is the essential feature preceding the early prefibrotic stage of AMM, the term essential megakaryocytic granulocytic metaplasia (EMGM) can readily be used to characterize this condition more appropriately at the biological level. Clinical, hematological and morphological characteristics, in particular megakaryocytopoiesis and bone marrow cellularity, reveal diagnostic features, which enable a clear-cut distinction between ET, PV and EMGM or classical IMF. The characteristic increase and clustering of enlarged megakaryocytes with mature cytoplasm and multilobulated nuclei and their tendency to cluster in a normal or only slightly increased cellular bone marrow represent the hallmark of ET. The characteristic increase and clustering of enlarged mature and pleiomorphic megakaryocytes with multilobulated nuclei and proliferation of erythropoiesis in a moderate to marked hypercellular bone marrow with hyperplasia of dilated sinuses are the specific diagnostic features of untreated PV. EMGM, including the early prefibrotic stages as well as the various myelofibrotic stages of classical IMF appear to be a distinct neoplastic dual proliferation of abnormal megakaryopoiesis and granulopoiesis. The histopathology of the bone marrow in prefibrotic EMGM and in classical IMF is dominated by atypical, enlarged and immature megakaryocytes with cloud-like immature nuclei, which are not seen in ET and PV at diagnosis and during follow-up. Myelofibrosis in ET, PV and EMGM is graded into: no reticulin fibrosis (MF0), early reticulin fibrosis (MF1), advanced reticulin sclerosis with minor or moderate collagen fibrosis (MF2) and advanced collagen fibrosis with osteosclerosis (MF3). Myelofibrosis is not a feature of ET at diagnosis and during long-term follow-up. Myelofibrosis may be present in a minority of PV-patients at diagnosis and usually becomes apparent during long-term follow-up in the majority of PV-patients. Myelofibrosis secondary to the abnormal megakaryocytic and granulocytic myeloproliferation constitutes a prominent feature in the majority of EMGM/IMF at time of diagnosis and usually progresses more or less rapidly during the natural history of the disease. Life expectancy is normal in ET, normal during the 1st ten years and compromised during the 2nd ten years follow-up in PV, but significantly shortened in the prefibrotic stage of EMGM as well as in the various myelosclerotic stages of classical IMF. First line treatment options in prospective randomized clinical trials of newly diagnosed MPD-patients are control of platelet function with low-dose aspirin versus reduction of platelet count with anagrelide, interferon or hydroxyurea in ET; control of platelet and erythrocyte counts by interferon alone versus bloodletting plus hydroxyurea on indication in PV; interferon versus no treatment in the early stages of EMGM; a wait and see strategy in the fibrotic stages of EMGM or classical IMF with favorable prognostic factors, and bone marrow transplantation in classical IMF with poor prognostic factors at presentation or during short-term follow-up.

Aspirin↗

Clinical outcome after autologous transplantation in non-Hodgkin's lymphoma patients with high international prognostic index (IPI).

BACKGROUND: Dose intensification and autologous stem cell transplantation as front-line therapy in non-Hodgkin's lymphoma patients (NHL) is a matter for debate, although preliminary data suggest a role for it in patients at high risk of resistance or relapse according to the international prognostic index (IPI). PURPOSE AND STUDY DESIGN: To compare retrospectively the clinical outcome of two cohorts of NHL patients with high-risk IPI treated with MACOP-B for 12 weeks (38 patients) or high-dose chemotherapy (44 patients) including eight weeks of MACOP-B, one or two intensification cycles with mitoxanthrone, dexamethasone, high-dose ara-C and finally BEAM chemotherapy with autologous hemopoietic progenitor cell transplantation. RESULTS: The actuarial estimate of event (progression, relapse or death)-free survival (EFS) at three years was better (58% vs. 41%, P = 0.08) for patients treated with intensive regimen even though the overall survival did not show a statistically significant difference (63% vs. 50%, P = 0.27). Multivariate analysis showed that the high-dose chemotherapy program was the only independent variable correlating with a reduction in the event rate. CONCLUSION: Early autologous stem-cell transplantation might improve the clinical outcome of high-risk patients according to IPI.

Adolescent↗

Stage-modified international prognostic index effectively predicts clinical outcome of localized primary gastric diffuse large B-cell lymphoma. International Extranodal Lymphoma Study Group (IELSG)

BACKGROUND: The definition of prognostic parameters in early stages of gastric lymphoma is still controversial. The aim of this retrospective analysis was to assess the value of the stage-modified international prognostic index (IPI) in predicting the outcome of a large, consecutive series of patients with PGL of diffuse large B-cell histology (DLCL). PATIENTS AND METHODS: Three hundred twelve consecutive, newly-diagnosed, patients with localized PGL (stages I-IIE according to the 'Lugano staging system for GI lymphomas') referred from April 1972 to December 1997 to eight Italian and one Swiss centers were reviewed and their outcomes updated to June 1998. One hundred three patients were treated with single-modality therapy, while two hundred four received combined-modality treatment, most of which included surgery and short-term chemotherapy. RESULTS: After a median follow-up of 66 months (range 0.6-300 months), 195 (64%) were alive in first continuous complete remission (CCR). The five-year estimates of overall survival (OS) and event-free survival (EFS) were 75% and 67%, respectively. OS and EFS varied according to IPI, from, respectively, 90% and 82% for patients with 0-1 risk factors, to 40% and 35% for patients with > or = 3 risk factors (P = 0.00001). Cox regression analysis showed that IPI was the strongest predictor of survival. CONCLUSIONS: This study shows that stage-modified IPI is an effective predictive model in patients with primary DLCL of the stomach, enabling identification of patients with significantly different outcomes.

Adolescent↗

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↗

Primary effusion lymphoma after heart transplantation: a new entity associated with human herpesvirus-8.

Deep immunosuppression and Epstein-Barr virus (EBV) infection promote the emergence of lymphoproliferative disorders in patients undergoing solid organ transplantation. In the last few years a new herpesvirus, named human herpesvirus-8 (HHV-8), has been identified in Kaposi's sarcoma and primary effusion lymphoma (PEL) developing in AIDS patients. Subsequently, the same viral DNA sequences have been identified in almost all cases of Kaposi's sarcoma emerged outside HIV infection, thus suggesting their possible pathogenetic role in this tumor. Similarly, the association between HHV-8 and PEL also emerged in cases without HIV infection, even though the total number of these patients is still limited. Here, we focus on the emergence of this unusual lymphoma in patients undergoing solid organ transplant and underline once again its association with the HHV-8. Moreover, despite the characteristic local growth of this peculiar type of lymphoma, we demonstrate at the molecular level, an early neoplastic spread to the bone marrow suggesting the need to investigate in more detail the origin of the disease, as well as the molecular mechanisms controlling its systemic dissemination.

Aged↗

Induction-consolidation with an idarubicin-containing regimen, unpurged marrow autograft, and post-graft chemotherapy in adult acute lymphoblastic leukaemia.

Between 1991 and 1993 we conducted a collaborative trial in adult acute lymphoblastic leukaemia, introducing an idarubicin (IDA)-containing regimen for induction and early consolidation, and increasing consolidation intensity with an autologous bone marrow transplantation phase (ABMT, patients aged <51 years) followed by further chemotherapy for 12 weeks and low-dose maintenance for 6 months (ABMT patients) or 18 months. 96 patients were evaluable for antileukaemic response after induction with vincristine-prednisone-L-asparaginase plus cumulative IDA 36 or 20 mg/m2 (IVAP-1 and IVAP-2), and for disease-free survival (DFS) after a minimum follow-up >3.5 years with an off-therapy interval >1.5 years. The response rate was 44% (7/16) with IVAP-1 and 90% (72/80) with IVAP-2 (P=0.0001), due to regimen-related toxicities. Post-remission therapy was administered as planned to most cases but protocol violation was registered in some patients eligible to ABMT and post-graft chemotherapy. The 5-year disease-free survival (DFS) rate was 31%. Multivariate analysis indicated that DFS was improved in patients receiving a transplant (11 allogeneic, DFS 70%; 32 ABMT, 36%; 37 neither, 17%; P < 0.001) and was negatively affected by high-risk features such as blast cell count >25x10(9)/l, T-cell or mature B-cell immunophenotype, and t(9;22)/t(4;11) (all P values <0.05). The 5-year DFS rate was 54% for 26 patients with no high-risk factor, 26% for 35 patients with any one, and 6% for 18 patients with any two (P<0.005). IVAP-2 brought about a high complete response rate and post-remission treatment including ABMT was feasible and modestly toxic. In spite of the short post-graft chemotherapy phase, the long-term DFS rate was good in cases with no high-risk feature. However, because autografting may be redundant in the standard-risk category, its role requires further investigation for high-risk cases.

Adolescent↗

Multicenter phase II study of fludarabine phosphate for patients with newly diagnosed lymphoplasmacytoid lymphoma, Waldenström's macroglobulinemia, and mantle-cell lymphoma.

PURPOSE: Fludarabine phosphate (F-AMP) has significant activity in follicular lymphoma and in B-cell chronic lymphatic leukemia, where it has demonstrated high complete response (CR) rates. Lymphoplasmacytoid (LPC) lymphoma, Waldenstrom's macroglobulinemia (WM), and mantle-cell lymphoma (MCL) also present with advanced-stage disease and are incurable with standard alkylator-based chemotherapy. A phase II trial was undertaken to determine the activity of F-AMP in patients newly diagnosed with these diseases. PATIENTS AND METHODS: Between 1992 and 1996, 78 patients (aged 18 to 75 years) received intravenous F-AMP (25 mg/m2/d for 5 days, every 4 weeks) until maximum response, plus two further cycles as consolidation. The primary end point was response rate; secondary end points included time to progression (TTP), duration of response, and overall survival (OS). RESULTS: Forty-four (62%) of 71 assessable patients had a response to F-AMP (LPC lymphoma, 63%; WM, 79%; MCL, 41%); the CR rate was 15%. At a median follow-up of 1.5 years, 19 of 44 responding patients have had progression of lymphoma; the median duration of response was 2.5 years. The median survival has not yet been reached. There was no significant difference in the duration of response or OS between patients with different histologies; TTP was shorter in patients with MCL (P = .015). Myelosuppression was relatively common, and the treatment-related mortality (TRM) was 5%, mostly associated with pancytopenia and infection. CONCLUSION: Single-agent fludarabine phosphate is active in previously untreated LPC lymphoma and WM, with only moderate activity in MCL. However, the CR rate is low, and the TRM is relatively high. Its role in combination chemotherapy remains to be demonstrated.

Adult↗

Cellular uptake and antiproliferative effects of therapeutic concentrations of idarubicin or daunorubicin and their alcohol metabolites, with or without cyclosporin A, in MDR1+ human leukemic cells.

Ways of restoring an altered drug sensitivity in P-170 glycoprotein (MDR1) positive leukemias are being actively sought for, mostly using MDRI negative regulators together with the MDR1-sensitive anthracycline-type drugs daunorubicin and mitoxantrone. Because idarubicin is less vulnerable to MDR1-mediated transport and could thereby represent a better companion to MDR1 inhibitors, we assessed the ability of the anti-MDR1 agent cyclosporin A to modulate this function in multidrug resistant T-lymphoblastic CEM cells challenged in vitro with either daunorubicin or idarubicin. In order to obtain information of potential interest for the design of a clinical trial, we adopted drug plus metabolite concentrations and exposure times close to the in vivo pharmacokinetics of equimyelotoxic doses of intravenous daunorubicin 45 mg/m2 or idarubicin 10-12 mg/m2, respectively, plus infusional cyclosporin A 16 mg/kg/d. Study methods were cytofluorimetry for the detection of intracellular drug uptake, retention and pro-apoptotic effects (binding of fluoresceinated annexin V), and the standard MTT assay as growth inhibition test. The results showed significantly greater drug uptake (at 30'), retention (at 12 hours), and apoptotic cell rates with idarubicin+/-idarubicinol than daunorubicin+/-daunorubicinol (p<0.05), and a further potentiation of these effects by cyclosporin A. Differing from daunorubicin, idarubicin intracellular accumulation and, by inference, related apoptotic changes were increased by cyclosporin A only in the early phase of drug-cell interaction; a potential advantage towards a reduced toxicity by CsA delivered as short rather than prolonged infusion in the in vivo setting. MTT assay results were also in favour of idarubicin but greatly influenced by cyclosporin A itself. Altogether, study results in MDR1+ cells incubated with CsA 1500 ng/ml plus idarubicin+idarubicinol 100+20 ng/ml, that are peak levels achievable in vivo with an idarubicin dose > or = 12 mg/m2 plus cyclosporin A 16 mg/kg/d, were in the range of those obtained with standard-dose daunorubicin in MDR1- cells (p=n.s.). In summary, an idarubicin plus short-course cyclosporin A combination could be considered for the management of MDR1+ leukemias, where it may represent a more effective and less toxic option than daunorubicin plus continuous infusion cyclosporin A.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Leucocyte alkaline phosphatase identifies terminally differentiated normal neutrophils and its lack in chronic myelogenous leukaemia is not dependent on p210 tyrosine kinase activity.

Leucocyte alkaline phosphatase (LAP) is a marker of post-mitotic granulocytes and its activity is reduced or absent in chronic myelogenous leukaemia (CML) granulocytes as a consequence of LAP messenger RNA (mRNA) deficiency. We provide evidence that along the granulocytic maturation in normal marrow, the acquisition of LAP surface expression, identified by the monoclonal antibody 1B12.1, was restricted to CD11bbright/CD16bright positive cells. Moreover, in normal granulocytes, exposure to granulocyte colony-stimulating factor (G-CSF) in vitro and in vivo increased the cell surface expression of LAP. Although G-CSF was able to induce the LAP surface expression in CML granulocytes, the inhibition of p210 tyrosine kinase activity by genistein or CGP75148B failed to restore LAP mRNA expression and LAP protein synthesis. In conclusion, the acquisition of LAP protein on the cell surface of granulocytes follows CD16 antigen expression and can be considered as the last marker of terminally differentiated neutrophils. G-CSF is a potent regulator of the LAP mRNA expression and protein synthesis in normal and CML-derived neutrophils. The lack of direct activity of p210 tyrosine kinase on LAP mRNA expression in CML neutrophils supports the notion that the LAP defect in this disease could be related to a precocious and uncontrolled release of white blood cells from the bone marrow into the blood stream.

Alkaline Phosphatase↗

The risk of thrombosis in patients with lupus anticoagulants is predicted by their specific coagulation profile.

Lupus anticoagulants belong to the family of antiphospholipid antibodies. They include two phospholipid-dependent inhibitors of coagulation that may be distinguished on the basis of specific coagulation profiles generated from the comparison of the ratios of the Kaolin Clotting Time (KCT) and the dilute Russell's Viper Venom Time (dRVVT): when the ratio of the KCT exceeds that of the dRVVT, the plasma is allocated to the "KCT" coagulation profile, when the opposite occurs, the plasma is defined to belong to the "dRVVT" coagulation profile group. We prospectively followed-up a historical cohort of 100 consecutive patients with lupus anticoagulants referred to our Institution between January 1988 and October 1997 to investigate the relationship between their coagulation profile at diagnosis and the development of thrombosis during a median follow-up time of 37.5 months (range 1-115 months). Fifty-six patients were allocated to the "dRVVT" coagulation profile, whereas the other 44 displayed the "KCT" profile. Lupus anticoagulants were transient in 17 patients, without differences between the two groups. None of these patients developed clinical events before disappearance of the phospholipid-dependent inhibitors of coagulation. The 83 cases with persistent lupus anticoagulants consistently displayed the same coagulation profile they had been allocated to at entry. Fourteen patients developed 18 thromboembolic events during the follow-up, with an overall rate of thrombosis of 4.2% patients-year. Twelve of them belonged to the "dRVVT" coagulation profile, whereas the other 2 to the "KCT" profile (p = 0.03). The "dRVVT" coagulation profile gave an odds ratio of thrombosis of 5.25 (95% confidence interval [C.I]: 1.17-23.50). Ten of the 14 patients who developed thrombosis during follow-up had already experienced thrombosis: a previous thrombotic event caused an odds ratio of recurrency of 2.72 (95% C.I.: 0.85-8.73) (p = 0.09). By multivariate analysis, the "dRVVT" coagulation profile was still associated with a trend to a higher risk of thrombosis, but the difference did not reach statistical significance. Increased levels of anticardiolipin antibodies (> 40 GPL and/or MPL units) were found in all the 14 patients (p = 0.0064). The "KCT" coagulation profile was significantly associated (p = 0.005) with moderate thrombocytopenia (platelets 50-150 X 10(9)/l). Neither profile was found to represent a risk factor for the development of recurrent miscarriages, neoplastic diseases and death. In conclusion, the "dRVVT" profile appears to have predictive value with respect to the thrombotic complications suffered by patients with antiphospholipid antibodies.

Adult↗

Fractionated cyclophosphamide added to the IVAP regimen (idarubicin-vincristine-L-asparaginase-prednisone) could lower the risk of primary refractory disease in T-lineage but not B-lineage acute lymphoblastic leukemia: first results from a phase II clinical study.

BACKGROUND AND OBJECTIVE: In a prior study, primary resistant acute lymphoblastic leukemia (RES-ALL) was observed in 11 of 176 (6%) adult patients treated with a four drug regimen (IVAP), its incidence being higher in T-cell or Philadelphia (Ph) chromosome/BCR-ABL rearrangement positive ALL cases with a blast cell count >25x10(9)/L (RES-ALL rate 19%, p=0.04). Aiming to minimize this percentage of resistant disease, fractionated cyclophosphamide (f-CY) was then added to the IVAP regimen. DESIGN AND METHODS: Study 08-96 was a prospective, collaborative phase II trial carried out at eight general hospital centers specialized in the care of hematologic malignancies. Historical IVAP-treated patients served as a retrospective control group. All consecutive, untreated patients (>15 years) with a diagnosis of ALL or advanced-stage lymphoblastic lymphoma (LBL) were eligible. RES-ALL was defined as the persistence of >5% ALL cells in the bone marrow 28-40 days after the start of the IVAP regimen (idarubicin 10 mg/m(2)/d on days 1 and 2; vincristine 2 mg on days 1, 8 and 15; L-asparaginase 6,000 U/m(2) on alternate days 3 6 from day 8; prednisone 60 mg/m(2)/d on days 1-21). In the new study, two f-CY schedules were sequentially adopted: CY 150 or 75 mg/m(2)/bd, given for 4 consecutive days before IVAP (f-CY 1200 or 600, expressing total CY dose in mg/m(2)). RESULTS: Eighty-eight patients were evaluable (age range 15-74 years, blast count 0-240x10(9)/L, 14 T-lineage, 74 B-lineage, 13 Ph/BCR-ABL+). The first 39 patients received the f-CY 1200 schedule, 22 patients received f-CY 600, and the last 27 patients were not given any f-CY. These changes were dictated by the results of interim analyses of the f-CY groups (RES-ALL rate not reduced, myelotoxicity increased). Altogether, compared with the historical IVAP and no f-CY groups, the incidence of RES-ALL was not decreased by the addition of f-CY 1200/600 in B-lineage ALL, regardless of Ph/BCR-ABL expression and blast count. However, none of 14 T-ALL cases in the new study had RES-ALL (8 in f-CY groups, 5 of whom with >25x10(9)/L blast cells), compared to 5/39 (13%, overall) or 4/21 (19%, with >25x10(9)/L blast cells) among the control cases. Owing to small sample size, this difference was not statistically significant. INTERPRETATION AND CONCLUSIONS: This preliminary experience suggests that T-ALL may be more sensitive than B-lineage ALL to an early therapy including f-CY. The hypothesis could be tested in a larger clinical trial.

Adolescent↗

Clinical parameters for determining when and when not to treat essential thrombocythemia.

Essential thrombocythemia (ET) is a myeloproliferative disorder that occurs primarily in middle-aged adults. ET is relatively benign compared with some of the other myeloproliferative disorders (MPDs), but there is still a high rate of morbidity and quality of life can be affected, especially by thrombotic and hemorrhagic complications. Two thirds of ET patients are symptomatic, but therapies are not benign. While alkylating agents, radioactive phosphorous, and hydroxyurea (HU) all have a leukemogenic risk, their use in high-risk and elderly patients may still be warranted in some circumstances. Use of nonmutagenic agents such as anagrelide, interferon-alpha (IFN), or low-dose aspirin has become an attractive alternative. However, the risks and benefits of treatment versus nontreatment should be based on clinical data and must be determined on an individual basis.

Humans↗

Cancer procoagulant and tissue factor are differently modulated by all-trans-retinoic acid in acute promyelocytic leukemia cells.

All-trans-retinoic acid (ATRA) downregulates the expression of two cellular procoagulants, tissue factor (TF) and cancer procoagulant (CP), in human promyelocytic leukemia cells. To evaluate whether or not changes of the procoagulant activities (PCAs) may share mechanisms with the ATRA-induced cyto-differentiation process, we have characterized the effect of ATRA on the TF and CP expression by NB4 cells, an ATRA maturation-inducible cell line, and two NB4-derived cell lines resistant to ATRA-induced maturation, the NB4. 306 and NB4.007/6 cells. Next, we evaluated the effect on the PCAs of the NB4 parental cells of three synthetic retinoid analogues, ie: AM580 (selective for the retinoic acid receptor [RAR] alpha), capable to induce the granulocytic differentiation of NB4 cells; and CD2019 (selective for RARbeta) and CD437 (selective for RARgamma), both lacking this capability. Cells were treated with either ATRA or the analogues (10(-6) to 10(-8) mol/L) for 96 hours. The effect on cell differentiation was evaluated by morphologic changes, cell proliferation, nitro blue tetrazolium reduction assay, and flow cytometry analysis of the CD33 and CD11b surface-antigen expression. PCA was first measured in 20 mmol/L Veronal Buffer cell extracts by the one-stage clotting assay of normal and FVII-deficient plasmas. Further TF and CP have been characterized and quantified in cell-sample preparations by chromogenic and immunological assays. In the first series of experiments, ATRA downregulates both TF and CP in NB4 parental cells, as expected. However, in the differentiation-resistant cell lines, it induced a significant loss of TF but had little or no effect on CP. In a second series of experiments, in the NB4 parental cells, the RARalpha agonist (AM580) induced cell maturation and reduced 91% CP expression, whereas CD437 and CD2019 had no cyto-differentiating effects and did not affect CP levels. On the other hand, in the same cells the TF expression was reduced by ATRA and AM580, but also by the RARbeta agonist CD2019, which did not induce cell maturation. These data indicate that in NB4 cells, ATRA modulation of CP occurs in parallel with signs of cell differentiation, while the regulation of TF appears to be at least in part independent from these processes, and involves both alpha and beta nuclear retinoid receptors.

Antineoplastic Agents↗