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A Thyss

Publications and source records attributed to A Thyss.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Population study of dihydropyrimidine dehydrogenase in cancer patients].

Dihydropyrimidine dehydrogenase (DPD) is the initial enzyme of 5-fluorouracil (5-FU) catabolism. The clinical importance of DPD has recently been demonstrated with the identification of severe and/or lethal 5-FU-related toxicity in patients with suspected or proven DPD deficiency revealed in lymphocytes. We conducted a prospective study on 185 cancer patients in order to evaluate the incidence of complete or partial DPD deficiency. The population comprised 152 men (mean age 62.1) and 33 women (mean age 59.2). Sixty eight were head and neck patients treated by a 5-day continuous infusion of 5-FU (starting dose 1 g/m2/day, with dose adaptation at mid-cycle) for which DPD activity was measured 2-3 days before 5-FU administration (94 cycles analyzed). DPD activity was measured by a radioenzymatic assay using 14C-5-FU. DPD activity showed a unimodal distribution, which globally fits a Gaussian distribution. Mean and median DPD activity were 0.222 and 0.211 nmol/min/mg prot respectively (range 0.065-0.559). No total DPD deficiency was found. Neither liver function nor age influenced DPD activity, but DPD activity was on average 15% lower in women than in men (0.194 and 0.228 nmol/min/mg prot respectively, p = 0.03). In patients treated with 5-FU, the risk of developing side effects was not linked to pretreatment DPD activity. 5-FU-related toxicity was linked to FU systemic exposure. The correlation between DPD activity and FU clearance was weak (n = 90, r = 0.31, p = 0.002). As a corollary, DPD activity in patients requiring a dose reduction was not significantly different from DPD activity in patients who did not require dose modification. From the present study it appears that total DPD deficiency is a very rare event. Although pre-treatment DPD activity cannot be a useful indicator for improving 5-FU dose adaptation strategy, the identification of partial DPD deficiency (< 0.100 nmol/min/mg prot, 3% of the population) could lead to starting the treatment with a markedly reduce 5-FU dose.

Adult↗
PubMed1995

Clinical and immunological follow-up of patients with AIDS-associated Kaposi's sarcoma treated with an anti-IL-6 monoclonal antibody.

Ten AIDS patients with Kaposi's sarcoma (four in stage II A, four in stage III A, one in stage III B and one in stage IV of the disease) were treated for 14 days with B-E8, an anti-IL-6 monoclonal antibody (IgG1), at a daily dose of 10 mg. No side-effects were observed, but no patients experienced a complete or partial response. No modification was noted in the analysis of lymphocyte subsets, except for a transient decline in the number of cells expressing CD56, accompanied by altered NK activity in four of the seven evaluable patients. Anti-IL-6 mAb prevented the binding of IL-6 to its cell membrane receptor, as documented by the decline in C reactive protein levels. However, anti-IL-6 mAb induced the circulation of significant amounts of IL-6, probably in the form of monomeric immune complexes. The sera, analysed on B9 cell line, demonstrated a stimulating activity, indicating that hypersensitive cells were able to cleave these complexes. This observation, together with the clinical inefficacy of the treatment, should prompt us to be careful with the use of unmanipulated single monoclonal antibodies, especially in cancer patients.

Acquired Immunodeficiency Syndrome↗
PubMed1994

High expression of the antigen recognized by the monoclonal antibody GB24 on human breast carcinomas: a preventive mechanism of malignant tumor cells against complement attack?

GB24 is a mouse monoclonal antibody raised against a common trophoblast-lymphocyte cross-reactive antigen. GB24 detects the membrane cofactor protein (MCP, CD46), a member of the complement regulatory protein family, which serves as a cofactor for factor 1 mediated cleavage of C3b. This study investigated the reactivity of GB24 on 38 breast carcinomas and 34 normal/benign breast tissues by immunochemistry as well as the reactivity of F2B7-2, an antibody specific to the decay accelerating factor (DAF, CD55) of the complement. GB24 staining was present on both normal tissue and benign lesions, but very strong diffuse reactivity was observed on carcinomas. This reactivity increased with the tumor grade. By contrast, malignant tumor cells lacked DAF expression. F2B7-2 antibody reacted weakly with benign epithelial cells. Results were studied by computer assisted image analysis to accurately define the mean optical densities. The densitometric analysis of MCP positive carcinomas showed a high intensity of the staining. Expression of MCP and DAF on MCF-7 cell lines was analyzed by flow cytometry. MCF-7 cell lines were strongly stained by mAb GB24 only. These data suggest that selectively enhanced expression of the antigen recognized by GB24 is associated with malignant breast disorders. This high expression, which may reflect a protective mechanism by which tumor cells survive complement activation, may prove useful as a marker of malignant transformation.

Adenocarcinoma↗
PubMed1994

Inhibition of dihydropyrimidine dehydrogenase by alpha-interferon: experimental data on human tumor cell lines.

Interferons (IFNs) are very promising fluorouracil (FU) biochemical modulators. The pharmacological origin sustaining the FU-IFN synergistic interaction is not clearly understood. It was recently shown that alpha-IFN was associated with a dose-dependent decrease in FU clearance in treated patients. Dihydropyrimidine dehydrogenase (DPD) is the key regulating enzyme for FU catabolism. The effects on DPD exerted by both the IFN dose and the duration of exposure were evaluated in a panel of five human cancer cell lines. All cell lines investigated exhibited quantifiable DPD activity with inter-cell-line variability (0.118-0.318 nmol min-1 mg protein-1). A prolonged exposure to IFN (up to 5 days) was necessary to obtain a significant inhibition of DPD activity. A concentration-dependent significant decrease in DPD activity, reaching 50% of the initial activity determined for the highest IFN concentration (10(5) IU/ml), was demonstrated in all cell lines tested (5-day IFN exposure). For three cell lines, IFN potentiated the FU-induced growth inhibition in a concentration-dependent manner. Considering all cell lines and all IFN concentrations, it appears that globally, the greater the inhibition of DPD activity, the greater the FU potentiation (Spearman rank correlation on all cell lines, P = 0.011).

Carcinoma↗
PubMed1994

Metastatic medulloblastoma: the experience of the French Cooperative M7 Group.

A retrospective analysis was performed to determine the outcome of children with metastatic medulloblastoma given a standardised treatment programme. Of 68 consecutive patients treated in the French M7 protocol for medulloblastoma, 23 presented with metastatic disease. They were uniformly treated with surgery, and the same protocol of chemotherapy and craniospinal radiotherapy. The 7-year relapse-free survival rate is 43% for metastatic patients compared to 68% for patients with localised disease. Survival did not correlate with age, sex, location of metastases, extent of initial surgery and the dose of radiation therapy on the posterior fossa. Survival did correlate with the dose to the cranial field with a threshold dose of 30 Gy. Patients with metastatic disease have a worse prognosis and require more aggressive therapies at initial presentation. The prognostic impact of the different sites of metastatic disease requires further evaluation in cooperative studies.

Adolescent↗
PubMed1994

A radiolabelled iodobenzamide for malignant melanoma staging.

123I-N-(di-ethylamino-2-ethyl) 4 iodobenzamide (I-BZA) has been put forward by the Clermont-Ferrand INSERM U71 group (France) as a tracer for malignant melanoma. We report on the clinical results obtained in 56 studies performed on 48 patients. Whole body scans along with spot views were obtained after injection of 185 MBq of I-BZA. The scans were read by three independent observers and correlated to the clinical findings and the other imaging modalities available, taking into account all lesions larger than 1 cm. Patients were classified into two groups on the basis of a post-treatment survey of patients: group I, in complete remission (24 scans); group II: documented metastases (32 scans). In group 1, 21 studies were truly negative. However, three studies showed positive results. Only one turned out to be a false positive (specificity 95%), the other two revealed unknown lesions and modified the patients' management. In group II, 73% of the known metastases were detected with higher sensitivities (> 80%) for eye and orbit, lung and abdomen. One false positive was reported and four new lesions were detected. I-BZA scintigraphy has the same sensitivity as immunoscintigraphy with higher specificity and without the risk of xenoimmunization. It is a useful tool for staging malignant melanoma which can improve patient management.

Aged↗
PubMed1994

Improved survival for acute lymphoblastic leukaemia in infancy: the experience of EORTC-Childhood Leukaemia Cooperative Group.

Out of 744 newly diagnosed ALL children under the age of 18 years treated according to the EORTC-CLCG protocols 58831 and 58832, 28 (4%) were infants less than 1 year of age. An elevated risk factor, which takes into account the sizes of the liver and spleen and the number of circulating blasts, was present in 25 cases. Most patients had non-common ALL. Among 15 patients studied by cytogenetics, nine present chromosomal abnormalities, six of them having a t(4;11) translocation. Complete remission was achieved in 86% of cases. One patient died in complete remission of therapy-related infection. The overall EFS is 43%. It is not statistically different in very young infants as compared to infants older than 6 months. Except for patients with AUL or with t(4;11) translocation, a continuous complete remission rate above 50% can be achieved with a median follow-up of 4 years. The results obtained in infant ALL with EORTC-CLCG protocols are currently better than those obtained with some other protocols, but remains inferior when compared to the ones obtained in older children. Thus, further improvements are needed and should be evaluated in large cooperative trials.

Age Factors↗
PubMed1994

Renal tolerance of cisplatin in patients more than 80 years old.

PURPOSE: Assessment of cisplatin (CDDP) tolerance in patients more than 80 years old in good general condition who may benefit from CDDP-based treatment. PATIENTS AND METHODS: Data on 35 patients older than 80 years who received one to six chemotherapy cycles (median, three cycles; total number of cycles, 98) including CDDP (60 to 100 mg/m2) were analyzed retrospectively. Before treatment, all patients had normal renal function as defined by serum creatinine (SC) levels below 132 mumol/L. Renal function was evaluated by measurement of SC and creatinine clearance (CC) before and after each course of chemotherapy. CC was calculated according to the Cockroft and Gault formula, where CC = (140 - age) x weight kg/0.814 x SC mumol/L. Renal toxicity was evaluated by the difference between prechemotherapy SC and the maximum SC level observed (delta SC) and by the difference between prechemotherapy CC and the minimal CC observed after treatment with CDDP (delta CC). The evolution of SC and CC during repeated courses of CDDP was analyzed, as were any extrarenal toxicities. RESULTS: Renal function remained stable in 19 patients (54%) with delta SC less than 18 mumol/L and 18 of 35 patients (51%) with delta CC less than 9 mL/min. A slight deterioration in renal function was observed in 13 patients (37%) with delta SC greater than 18 mumol/L and less than 60 mumol/L, and with a delta CC greater than 11 mL/min and less than 21 mL/min. In three patients (9%), delta SC was greater than 60 mumol/L (71, 73, 115 mumol/L) and delta CC was greater than 21 mL/min (25, 26, 36 mL/min). There were no cases of severe renal insufficiency, clinical ototoxicity, or neurotoxicity > or = grade 2. Treatment was terminated after one or two courses in three patients because of grade 2 or 3 hematologic toxicity and in two patients for grade 3 nausea or vomiting. CONCLUSION: CDDP at moderate doses can reasonably be administered to patients older than 80 years who may benefit from antineoplastic chemotherapy.

Aged↗
PubMed1994

Population study of dihydropyrimidine dehydrogenase in cancer patients.

PURPOSE: We conducted a prospective study on a large set of cancer patients in an attempt to evaluate the incidence of complete or partial dihydropyrimidine dehydrogenase (DPD) deficiency as found in peripheral mononuclear cells (PMNC). PATIENTS AND METHODS: One hundred eighty-five unselected consecutive cancer patients were included. The population consisted of 152 men (mean age, 62.1 years; range, 35 to 90) and 33 women (mean age, 59.2 years; range, 36 to 77). Sixty-eight were head and neck patients treated by a 5-day continuous infusion of fluorouracil (FU; starting dose, 1 g/m2/d, with dose adaptation based on pharmacokinetics) for which DPD activity was measured 2 to 3 days before FU administration (94 cycles analyzed). PMNC-DPD activity was measured by a radio-enzymatic assay using carbon-14-FU. RESULTS: DPD activity in the entire population showed a unimodal distribution, which globally fits a gaussian distribution. Mean and median DPD activity values were 0.222 and 0.211 nmol/min/mg protein, respectively (range, 0.065 to 0.559). No total DPD deficiency was found. Multifactor analysis of variance showed that liver function (biologic evaluation) and age did not influence DPD activity, but that DPD activity was, on average, 15% lower in women (0.194 nmol/min/mg protein) than in men (0.228 nmol/min/mg protein) (P = .03). No difference was demonstrated between premenopausal and postmenopausal women. In patients treated with FU, the risk of developing side effects was not linked to pretreatment DPD activity. FU-related toxicity was linked to FU systemic exposure. The correlation between pretreatment DPD activity and FU systemic clearance (CI) was weak (n = 90, linear regression r = .31, P = .002). Pretreatment DPD activity in patients who required a dose reduction was not significantly different from DPD activity in patients who did not require dose modification. CONCLUSION: From the present study, it appears that total DPD deficiency is a rare event. Although pretreatment DPD activity cannot be a useful indicator for improving FU dose adaptation strategy, the identification of severe DPD deficiency (< 0.100 nmol/min/mg protein) could lead to starting the treatment with a markedly reduced FU dose or even to using an alternative chemotherapy regimen.

Adult↗
PubMed1994

Relationship between fluorouracil systemic exposure and tumor response and patient survival.

PURPOSE: The aim of this study was to analyze the link between fluorouracil (FU) systemic exposure and tumor response and overall survival. PATIENTS AND METHODS: One hundred eighty-six patients (162 men, 24 women) with head and neck cancer were studied. All received cisplatin plus FU for three cycles as first-line chemotherapy. The treatment consisted of cisplatin (100 mg/m2 intravenously [IV]) followed by a 5-day continuous venous infusion of FU (1 g/m2/d). The median follow-up duration for the 104 patients alive was 24 months. For each cycle, we calculated the area under the curve over the duration of pharmacokinetic follow-up (AUC0-105 h) for plasma FU. For each patient, we analyzed the averaged AUC0-105 h and the averaged total dose for the three cycles. RESULTS: The response rate was 30% complete responses (CRs), 22% partial responses (PRs) more than 75%, 25% PRs less than 75%, and 23% no response (NR). Medians for averaged AUC and dose per cycle were 27,906 ng/mL h (first through third quartile, 25,398 to 31,060) and 7,000 mg (first through third quartile, 6,200 to 7,833), respectively. The tumor response was significantly linked to tumor stage (P < .001) and to averaged AUC (P = .05), but not to averaged dose. Analysis of parameters (continuous variable) expressing FU treatment intensity showed that dose did not influence survival contrary to the AUC (P = .001). The AUC remains significant (P = .025) in a multivariate analysis including tumor stage, demonstrating that the greater the FU systemic exposure, the longer the survival. CONCLUSION: These results strengthen the interest of individual FU dose adaptation based on pharmacokinetics.

Adult↗
PubMed1994

Cerebrospinal fluid drug levels of leukemic children receiving intravenous 5 g/m2 methotrexate.

A multicenter prospective study was conducted in 114 children with acute lymphoblastic leukemia receiving 4 intravenous methotrexate (MTX) courses (5 g/m2 as a 24 hour-infusion) to determine the diffusion of MTX in cerebrospinal fluid (CSF) and to correlate the drug levels to central nervous system (CNS) relapse occurrence. Serum and CSF levels were measured at the end of 446 MTX courses. A significant correlation was found between CSF and serum MTX concentration. CSF MTX level was greater than 1 mumol/l in 66% of the courses. Twelve patients (11%) failed to achieve this potentially cytotoxic drug level at the end of the 4 consecutive MTX courses: only one CNS relapse was observed and the mean age of these children was lower than that of the others. To date 9 (7.8%) children had CNS relapse and no difference was observed in terms of CSF MTX levels when compared to data of children free of CNS relapse. With a median follow up of 32 months, pharmacokinetic data during high-dose MTX therapy do not seem to be an exclusive predictive factor of CNS relapse.

Adolescent↗
PubMed1993

Human immunodeficiency virus-related lymphoma treatment with intensive combination chemotherapy. French-Italian Cooperative Group.

PURPOSE: An increased risk of high-grade non-Hodgkin's lymphoma is observed in patients who are seropositive for human immunodeficiency virus (HIV). Treatment of such patients is complicated by their underlying acquired immunodeficiency syndrome (AIDS). Intensive strategies such as those used in non-HIV-related lymphoma may be poorly tolerated. However, patients without severe AIDS may derive significant benefits from such an approach. In a prospective multicenter study, treatment outcomes were assessed in 141 cases of HIV-seropositive lymphomas submitted to aggressive chemotherapy. PATIENTS AND METHODS: Adult patients with lymphoma with a performance status less than 3 and no active opportunistic infection were consecutively treated with three cycles of doxorubicin 75 mg/m2, cyclophosphamide 1,200 mg/m2, vindesine 2 mg/m2 for 2 days, bleomycin 10 mg for 2 days, and prednisolone 60 mg/m2 for 5 days (ACVB). This treatment was followed by a consolidation phase of high-dose methotrexate plus leucovorin, ifosfamide, etoposide, asparaginase, and cytarabine (LNH84). Central nervous system prophylaxis with intrathecal methotrexate was routinely used. Zidovudine maintenance therapy was started after chemotherapy. Ninety-three patients had high-grade lymphomas (59 Burkitt's type) and 48 had intermediate-grade lymphomas. Disseminated stage III-IV was present in 86 patients, meningeal involvement in 29, and bone marrow infiltration in 30; 62 patients had more than 2 extranodal localizations. Lactate dehydrogenase levels were above the normal value in 95 cases. The median CD4-positive lymphocyte count was 227 x 10(6)/L. RESULTS: Eighty-nine patients (63%) achieved complete remission (CR) and 19 (13%) partial remission, whereas 13 did not respond and 20 (14%) died during the course of ACVB, 8 of them from progressive disease. With a median follow-up of 28 months, median survival and disease-free survival were 9 and 16 months, respectively. Median survival for nonresponders was 5 months; 23 patients died of opportunistic infections while in persistent CR. In multivariate analysis, four factors were strongly associated with shorter survival: (1) CD4 count less than 100 x 10(6)/L, (2) performance status greater than 1, (3) immunoblastic lymphoma, and (4) prior AIDS. In the absence of all risk factors, the probability of survival at 2 years was 50%. CONCLUSION: In a selected group of HIV-related lymphomas, intensive chemotherapy with LNH84 is feasible and yields a high CR rate. Survival is short due to death from HIV-related infections; however, in a subgroup of patients without adverse prognostic factors, long-term remission was observed.

Adult↗
PubMed1993

Toxoplasma cystitis associated with acquired immunodeficiency syndrome.

Ante-mortem diagnosis of vesical toxoplasmosis in a patient with acquired immunodeficiency syndrome (AIDS), was made by cystoscopic examination and biopsy of the bladder. Vesical biopsies can be helpful in determining appropriate therapy for AIDS patients with urinary tract involvement/disease.

Acquired Immunodeficiency Syndrome↗