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X Thomas

Publications and source records attributed to X Thomas.

At least 91 records · Page 5Linked to original sources
PubMed1995

[Bases for intravenous administration of cytosine arabinoside in the treatment of adult acute myeloid leukemia].

Cytosine arabinoside (Ara-C) is one of the most active drugs in the treatment of adult acute myeloid leukemia and is widely applied at all phases of therapy. In spite of its extensive clinical use, controversies exist about the most appropriate way and dose of intravenous administration: continuous or bolus infusion and standard-, intermediate- or high-dose. The present review focuses on the role and place of each modality of administration of Ara-C and on the potential interest on hematopoietic growth factors recently given concomitantly to Ara-C therapy. Based on available clinical and experimental data, the following conclusions can be drawn: conventional continuous infusion Ara-C-based regimens remain the standard therapy regarding first remission induction. The use of high-dose Ara-C has been followed by improved results in patients with slow initial cytoreduction after a first course of treatment and is an interesting approach for consolidation protocols. In relapsed and refractory adult acute myeloid leukemia, higher than conventional doses undoubtedly enhance the efficacy of Ara-C salvage therapy. Encouraging results emerge from the association of hematopoietic growth factors administered concomitantly to Ara-C based regimens, which need confirmation in prospective randomized placebo controlled comparative trials.

Adult↗
PubMed1994

Prospective genetically randomized comparison between intensive postinduction chemotherapy and bone marrow transplantation in adults with newly diagnosed acute myeloid leukemia.

PURPOSE: To compare intensive chemotherapy and HLA-identical allogeneic bone marrow transplantation (BMT) as postinduction therapy in young adults with acute myeloid leukemia (AML). PATIENTS AND METHODS: Seventy-eight consecutive AML patients younger than 40 years of age were treated according to a prospective protocol in which every patient in complete remission (CR) with an HLA-identical sibling was scheduled to receive BMT rather than intensive chemotherapy consolidation. To minimize comparison biases, the availability or not of an HLA-identical sibling donor was considered to be the equivalent of genetic randomization to the BMT or chemotherapy arm, respectively. RESULTS: Fifty-eight patients (74%) achieved a CR. A donor was found for 27 patients (BMT arm), and 20 of these patients were actually transplanted in first CR. The 31 patients without a donor were allocated to the chemotherapy arm. Patients in the two arms had similar disease characteristics at diagnosis and previous responses to induction therapy. The cumulative risk of relapse was 43% +/- 24% in the BMT arm and 67% +/- 19% in the chemotherapy arm (P = .01). The 7-year leukemia-free survival (LFS) rate was 41% +/- 20% in the BMT arm and 27% +/- 16% in the chemotherapy arm, a difference that is not statistically significant between the two arms. The overall survival rates were 41% +/- 20% and 46% +/- 19%, respectively. CONCLUSION: In this study, the availability of an HLA-identical sibling donor was not associated with a better survival rate because of both the impossibility of some patients with a donor to receive BMT and the more efficient salvage treatment of patients who relapsed after intensive consolidation chemotherapy than of patients who relapsed after BMT.

Acute Disease↗
PubMed1993

Potential role for non-HLA-restricted cytotoxic cells in the immune surveillance of acute leukemia.

The observation of more frequent leukemias in immune deficiencies of the non-HLA-restricted cytotoxic cell system and the participation of this system in the anti-leukemic effect of allogeneic bone marrow transplantation in acute leukemia indicate that these cells might play a role in the immune surveillance against leukemia. In order to find more direct evidence of this role we studied the susceptibility of leukemic cells to lysis by non-HLA-restricted cytotoxic cells, the functional value of these cells in leukemic patients in complete remission (CR), and expression by leukemic cells of adhesion molecules CD54 and CD58, which play a role in the adherence between cytotoxic cells and their targets. Our results are concordant to confirm a potential role of non-HLA-restricted cytotoxic cells in the immune surveillance of acute leukemia based on increased relapse rate in acute myeloid leukemia patients with no inducible lymphokine-activated killer (LAK) cell activity during CR, short survival of acute lymphoblastic leukemia patients whose blast cells are resistant to lysis by LAK cells, and poor overall prognosis of leukemias which do not express CD58.

Antibodies, Monoclonal↗
PubMed1992

Maintenance with low-dose cytarabine for acute myeloid leukemia in complete remission.

Thirty-four patients with acute myeloid leukemia (AML) in complete remission (CR), 30 of them aged over 60, received maintenance therapy scheduling four courses of low-dose cytarabine (LDA) 20 mg/m2/day in two subcutaneous injections for 3 weeks every 6 weeks. Each course was stopped when hematologic toxicity occurred, and doses of LDA were subsequently reduced by 50% for the following courses. During the first course of LDA, 15 patients needed blood and four patients platelet transfusions. Overall, 28 patients received four courses of LDA: 11 did not require any dose reduction, while 14 required one dose reduction and three needed two successive dose reductions. Two patients were hospitalized during maintenance. Median disease-free survival (DFS) is 308 days, with 16% of patients surviving at 5 years. Seven patients relapsed during the 168 days of maintenance, while ten of the 27 patients remaining at risk on day 169 relapsed during the 168 days following maintenance. We conclude that in AML in CR, the maximal dose of LDA tolerated by ambulatory patients is 10 mg/m2/day for 3 weeks. LDA seemed to delay relapse; however, precise assessment of the efficacy of this approach would require a randomized trial.

Acute Disease↗
PubMed1992

Surface marker expression in acute myeloid leukaemia at first relapse.

Surface markers were studied at first relapse in 66 cases of acute myeloid leukaemia (AML), using a panel of five monoclonal antibodies directed to CD13, CD14, CD15, CD33 and CD34 antigens. At time of relapse, there was increased expression of CD33 (P = 0.002) and CD34 (P = 0.0001), and decreased expression of CD13 (P = 0.004) and CD15 (P = 0.0001) antigens by comparison to initial diagnosis. There was no strict correlation with the FAB classification. However, CD13 and CD33 expression changes preferentially affected granulocytic leukaemias. At relapse, CD14 and CD34 were significantly more expressed in monocytic than in granulocytic AML (P = 0.01 and 0.003 respectively). In a multivariate analysis, CD34 expression was associated with a low CR rate (P = 0.001) and short survival (P = 0.05), whereas CD15 expression was associated with long survival (P = 0.0004). These results suggest that AML tends to relapse with a less differentiated phenotype than observed at diagnosis and that AML with less differentiated phenotype is of poor prognosis after first relapse, as also observed at diagnosis.

Acute Disease↗
PubMed1992

Expression of surface adhesion molecules CD54 (ICAM-1) and CD58 (LFA-3) in adult acute leukemia: relationship with initial characteristics and prognosis.

Adhesion molecules CD58 and CD54 are involved in cell-cell interactions that are potentially important in the biology of acute leukemia (AL). Expression of these molecules was studied in 79 cases of adult AL including 50 cases of acute non-lymphoid leukemia (ANLL) and 29 cases of acute lymphoid leukemia (ALL) using an indirect immunofluorescence technique. CD58 was expressed in 45 +/- 26% of ANLL cells and 43 +/- 32% of ALL cells, and its expression did not correlate with any other marker. In ALL, the expression of CD58 was inversely correlated with the presence of a clinical tumoral syndrome (p = 0.0009), leucocytosis (p = 0.005), and the percent of peripheral blast cells (p = 0.001). The major finding in this study was the association between CD58 expression and prognosis. In ANLL, higher expression of CD58 was independently associated with higher CR rate (p = 0.04), longer overall survival (p = 0.02), and longer disease-free survival (p = 0.007). In ALL, higher expression of CD58 was associated with longer survival (p = 0.05). CD54 was expressed only on 17 +/- 16% of ANLL cells and 11 +/- 11% of ALL cells; its expression on ANLL was positively correlated with that of CD11 (p = 0.03), CD15 (p = 0.001) and CD34 (p = 0.01). CD54 expression did not correlate with clinical and hematologic characteristics. We conclude that the expression of adhesion molecule CD58, but not CD54, in AL is related to initial characteristics and evolution of the disease.

Acute Disease↗
PubMed1992

Continuous-infusion daunorubicin and carboplatin for high-risk acute myeloid leukemia in the elderly.

Since continuous infusion of daunorubicin and of carboplatin have shown efficacy and reduced toxicity in early phase studies in acute myeloid leukemia (AML), 34 elderly patients with high-risk AML were treated with continuous infusion daunorubicin, 30 mg/m2 per day, from day 1 to day 4, and carboplatin, 200 mg/m2 per day from day 3 to day 7. Seven patients had therapy-related AML and/or AML following a myelodysplastic syndrome at diagnosis, 15 were in first and two in second relapse, and 10 were resistant to previous anthracycline and cytarabine therapy. Nine patients or 26%, with a 95% confidence interval (CI) ranging from 18-67%, achieved complete remission, including one patient at diagnosis (14%, CI: 0-58%), seven with relapsed AML (41%, CI: 18-67%), and one with resistant AML (10%, CI: 0-45%). Median durations of neutropenia below 0.5 x 10(9)/l and of thrombocytopenia below 20 x 10(9)/l were 24 and 20 days respectively. Severe toxicity included infections in 20 patients (59%), bleeding in two (6%), cardiac anomalies in two (6%), and vomiting in one (3%). Overall four patients (12%) died from chemotherapy related toxicity and 21 (62%) had resistant disease. Median overall survival was 4 months and median disease-free survival 8 months. We conclude that this regimen had efficacy with reduced toxicity in relapsed patients. Higher dosages for the same drugs could be tolerated by better risk patients for precise evaluation of cross reactivity with cytarabine-based regimens.

Acute Disease↗
PubMed1991

Antiemetic activity of high-dose methylprednisolone associated with continuous-infusion metoclopramide and oral alprazolam during multiple-day chemotherapy.

The addition of high-dose methylprednisolone (120 mg given i.v. and repeated after a 4-h interval) to a conventional antiemetic regimen consisting of metoclopramide (0.5 mg/kg given as an i.v. bolus over 30 min followed by 1 mg/kg given as a continuous infusion over 24 h) and alprazolam (0.5 mg given p.o.) was evaluated in a randomized study of leukemic patients undergoing anthracycline-containing multiple-day chemotherapy. Double-blind analysis was done in 30 patients who completed a total of 40 treatment courses. Cumulative 3-day results revealed complete control of nausea in 66% of patients and complete control of emesis in 77% of cases. The addition of methylprednisolone significantly reduced the occurrence of nausea (p = 0.003) and emesis (P = 0.06). Moreover, antiemetic rescue with chlorpromazine was less frequently necessary in patients receiving corticosteroids (P = 0.02). No harmful side effect was observed, and the incidence of severe infectious episodes was similar in both arms. We conclude that high-dose methylprednisolone can improve the efficacy of metoclopramide and alprazolam in controlling nausea and emesis induced by anthracycline-containing multiple-day chemotherapy in patients with acute myeloblastic leukemia.

Adolescent↗
PubMed1991

In vitro effects of recombinant hemopoietic growth factors on progenitor cells from patients with myelodysplastic syndromes.

The effects of four recombinant hemopoietic growth factors (HGF) and of the impure factor HTB9 on proliferation and maturation of marrow myeloid (CFU-GM) and erythroid (BFU-E) progenitor cells were studied in 22 cases of myelodysplastic syndromes (MDS). In most cases, IL-3, GM-CSF and G-CSF increased significantly the number of myeloid colonies, the best combination being IL-3 + GM-CSF. A significant increase in the myeloid colony/cluster ratio was also noted, but cytological examination of colony cells showed little maturation. The analysis of myeloid colony surface markers with four monoclonal antibodies (to CD13, CD15, CD33 and CD34) showed minor modifications with an increase of CD13 and CD15 in about one third of cases when compared to control without HGF. Erythroid colonies were obtained in one case with erythropoietin alone, and in 19 cases with the addition of GM-CSF and/or IL-3. In short-term liquid cultures, IL-3, GM-CSF and G-CSF increased 3H-thymidine incorporation. We conclude that progenitor cells of most MDS are able to proliferate in the presence of HGF, with wide case-to-case variations. However, the pattern of growth remains abnormal when compared to normal marrow. Although the combination of IL-3 and GM-CSF is the most efficient, there is a large overlap in the stimulating effects of all factors studied.

Antigens, CD↗
PubMed1991

Pefloxacin and vancomycin vs. gentamicin, colistin sulphate and vancomycin for prevention of infections in granulocytopenic patients: a randomised double-blind study.

To test the value of pefloxacin for the prevention of infections in patients with chemotherapy-induced neutropenia, oral pefloxacin plus vancomycin (PV) (n = 76) or gentamicin, colistin sulphate and vancomycin (GCV) (n = 74) were administered in a randomised double-blind study. Infections were significantly less severe in the PV than in the GCV group. Patients receiving PV had significantly fewer episodes of bacteraemia and central venous line infections than patients treated with GCV. Gram-positive and gram-negative infections were significantly less frequent in patients receiving PV, because of fewer infections with Staphylococcus species and enterobacteriaceae. Stool culture detected significantly more gram-positive organisms in the PV group and more gram-negative organisms in the GCV group. Thus, PV was more efficacious than GCV for the prevention of gram-positive and gram-negative infections in the neutropenic patients, despite lower efficacy in eradicating gram-positive organisms from the lower intestinal tract.

Adult↗
PubMed1991

High risk myelodysplastic syndrome coexistent with chronic lymphocytic leukemia for more than 9 years: inhibition of the myeloid clone by the lymphoid clone?

We describe a patient in whom the concomitant diagnosis of refractory anemia with excess of blasts (16% on initial marrow examination) and chronic lymphocytic leukemia was made more than 9 years ago. The myeloid clone showed a complex karyotypic abnormality. Evolution has so far been remarkably stable, without transformation into acute leukemia. Clonogenic assays showed that patient's serum inhibited the patient's own granulocyte-macrophage colony-forming units (CFU-GM). This inhibition was also present for a control subject's CFU-GM and acute myeloid leukemia clonogenic cells. This raises the problem of a down-regulation of the myeloid clone by the malignant lymphoid clone in this patient, and the possible mechanisms for this are discussed.

Bone Marrow↗
PubMed1991

Susceptibility of adult acute lymphoblastic leukemia blasts to lysis by lymphokine-activated killer cells.

To help understand host-tumor relationships in adult acute lymphoblastic leukemia (ALL) and to better define potential indications for interleukin-2 (IL-2) treatment in this disease, the relationship between the susceptibility of leukemia cells of 22 patients with ALL to lysis by allogeneic lymphokine-activated killer (LAK) cells and characteristics of the leukemia was studied. Lymphocytes were activated in the presence of 1000 U/ml recombinant IL-2 for 5 days. The lysis of ALL cells was studied by the release of 51Cr. The average lysis of ALL cells by control, unactivated lymphocytes was 1.2 +/- 2.4% and by LAK cells 8.9 +/- 8.6%. The susceptibility of leukemic cells to lysis did not correlate with the expression of lymphoid or myeloid differentiation markers or expression of the adhesion molecules CD54 (ICAM-1) and CD58 (LFA-3). Leukemic cells of the FAB I2 subtype were significantly more resistant to lysis than those of the other subtypes (average lysis 1.4 +/- 3.0% versus 12.3 +/- 8.2%, p = 0.003). The susceptibility to lysis did not correlate with the other initial characteristics of the leukemia. The 11 patients in whom 8% or more of leukemic cells were lysed by allogeneic LAK cells survived significantly longer than the 11 patients whose blast cells were less susceptible to lysis (p = 0.04). It is concluded that IL-2 treatment might be of benefit in adult ALL, particularly in non-L2 FAB subtypes and during complete remission to possibly delay relapse and prolong survival.

Adult↗
PubMed1990

[Prognosis of acute pneumococcal respiratory insufficiency requiring mechanical ventilation].

A retrospective study was carried out between 1980 and 1988 in an attempt to determine the prognostic factors in pneumococcal pneumonia requiring mechanical ventilation. Thirty-six of the 57 patients studied died (63 per cent). The initial severity of the lung disease, was the same in the patients who died and in those who survived. The risk of death was associated with the severity of the septic syndrome, as evaluated by the presence of septic shock, acute renal failure and disseminated intravascular coagulation.

Acute Disease↗
PubMed1990

Myelodysplastic syndromes: a study of surface markers and in vitro growth patterns.

A study of surface markers and in vitro growth in semi-solid and liquid medium was performed in 35 patients with newly diagnosed myelodysplastic syndrome (MDS). Surface markers were studied by CD34, CD13, CD14, CD15, and CD33 monoclonal antibodies. There was no strict correlation with the FAB typing, but CD34 was expressed only in refractory anemia with excess of blasts (RAEB) or RAEB in transformation (RAEB-t). CD14 was markedly positive in the 4 cases of chronic myelomonocytic leukemia. Colony-forming cells were assessed by culture in semi-solid medium in the presence of HTB9 as growth factor. Four growth patterns were identified: a) normal growth (6 cases); b) no growth or low plating efficiency (10 cases); c) low colony and high cluster number (15 cases); and d) normal or high colony number with high number of clusters (4 cases). Expression of CD34 was associated with low colony and high cluster number. Finally we studied the proliferation and differentiation capacities in liquid culture without stimulating factor. Fifteen patients had a spontaneous proliferation. This was not correlated with any surface marker. Differentiation assessed by the loss of CD34 and/or the increase of CD15 by more than 20% at day 7 was observed in 21 cases. None of the surface markers or growth patterns was associated with a specific chromosomal abnormality, except the lack of growth in liquid culture observed in all 5q deletion cases. In univariate analysis, RAEB and RAEB-t FAB subtypes, percentage of blasts higher than 5%, staining by CD33 and CD34, and lack of differentiation in liquid culture were significantly associated with progression to leukemia and shorter survival. In multivariate analysis, only CD34 expression (P = .002) and percentage of blasts (P = .05) remained independent significant variables. CD34 was the only significant variable for prediction of survival (P = .05). It is concluded that surface marker analysis at diagnosis and after liquid culture may be a useful tool for the initial evaluation of MDS.

Antigens, CD↗