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Biomedical subjects

F Porzsolt

Publications and source records attributed to F Porzsolt.

At least 73 records · Page 4Linked to original sources

Goals of palliative cancer therapy.

The major conclusions of the Workshop on Goals of Palliative Cancer Therapy are as follows: 1. The goals of any cancer therapy should be stated explicitly. 2. If the goal of treatment is palliation, this should be documented according to one of the established and validated methods for assessment of quality of life. Several validated methods are available, and although imperfect, have been shown to give reliable information. 3. The use of simple measures of quality of life (eg, symptom checklists, pain assessment cards) should become routine in oncology practice. The act of introducing such measures improves palliation. 4. Measures of cost-effectiveness should be used more widely in clinical decision making to ensure the appropriate deployment of resources. 5. There must be improved education of all health professionals with regard to the multiple methods for provision of palliative treatment to cancer patients and the assessment of palliation.

Cost-Benefit Analysis↗

Soluble tumor necrosis factor receptors correlate with parasitemia and disease severity in human malaria.

Elevated serum or plasma concentration of immunoreactive tumor necrosis factor (TNF) is consistently detected in patients with malaria. TNF levels correlate with high parasitemia and clinical severity but not always with outcome. Since the effects of TNF may be neutralized by soluble TNF receptors, sera of 30 nonimmune patients with malaria were analyzed before and during antimalarial therapy. High concentrations of receptors R1 (55 kDa) and R2 (75 kDa) were detected immunologically in all sera of untreated patients. Levels of immunoreactive TNF correlated closely with levels of soluble TNF R1 and R2 (r = .75 and .59, respectively). In contrast, sera lacked cytotoxic activity against target cells in the TNF bioassays. Soluble TNF receptor levels remained elevated for days after treatment. These results suggest that excessive release of TNF induced by the asexual stage of malaria parasites is controlled by a subsequent shedding of soluble TNF receptors that may bind and deactivate biologically functional TNF.

Adolescent↗

High levels of circulating soluble receptors for tumor necrosis factor in hairy cell leukemia and type B chronic lymphocytic leukemia.

The presence of soluble tumor necrosis factor (TNF) binding proteins (BP) was investigated in the sera of healthy volunteer blood donors and cancer patients. Two distinct types of TNFBP, types A and B, which are immunologically related to the cellular 75-kD TNF receptor (TNFR) and the cellular 55-kD TNFR, respectively, were assessed by immunoassays using nonblocking anti-receptor antibodies and 125I-recombinant human TNF alpha. As compared to the titers observed in 25 healthy controls, TNFBP types A and B titers were found to be elevated in almost all sera obtained from patients with underlying malignant disease. The highest amounts of TNFBP were seen in the sera of patients with B cell malignancies including hairy cell leukemia (HCL) and type B chronic lymphocytic leukemia. Treatment of HCL patients with recombinant human interferon-alpha was associated with decrease of circulating TNFBP.

Humans↗

Human interleukin-7 induces proliferation of neoplastic cells from chronic lymphocytic leukemia and acute leukemias.

The biologic effects of interleukin-7 (IL-7) and the expression of specific IL-7 membrane receptors on isolated neoplastic cells from previously untreated patients with chronic lymphocytic leukemia as well as acute leukemias were investigated in vitro. Leukemic cells were incubated for up to 6 days with various concentrations of IL-7 (0.01 to 2,000 U/mL). Neoplastic cells of the T- or B-phenotype from chronic as well as from acute leukemias proliferated in a dose-dependent manner. Cells from acute myeloid leukemias also proliferated in response to IL-7. An optimal proliferative effect was achieved between 96 and 120 hours with 200 U/mL IL-7. Combinations of IL-7 with IL-2 and tumor necrosis factor-alpha showed an additive effect on [3H]TdR incorporation. IL-7 binding assays gave a value of approximately 33 to 180 high-affinity (kd approximately 20 pmol/L) binding sites/cell and approximately 241 to 3,280 low-affinity (kd approximately 600 pmol/L) binding sites/cell. Receptor expression correlated with the proliferation in response to IL-7. These data indicate that IL-7 can induce proliferation of relatively mature tumor cells, and that this effect is not restricted to the lymphoid lineage.

Adult↗

Pharmacokinetics and biological activity in subcutaneous long-term administration of recombinant interferon-gamma in cancer patients.

We have investigated the pharmacokinetics, tolerance, and biological activity of recombinant human interferon-gamma (rHuIFN gamma) administered subcutaneously to cancer patients. Twenty-one patients with lymphoma and metastatic cancer received rHuIFN gamma (in doses of 0.1, 0.25, or 0.5 mg/m2) in two or three injections per week for up to 180 days. The most common adverse effects encountered were flu-like symptoms, fever and fatigue. The increase in body temperature after each administration ranged from 0 to 4 degrees C depending on the individual patient, but was unrelated to the rHuIFN gamma dose or its plasma concentration. The pharmacokinetic response of the patients after the two treatments showed a low intra-individual variability with respect to the plasma concentration/time profiles. However, as observed for the fever side-effect, the interindividual variation (CV greater than 50%) was high for the parameters area under the data points (AUC0-t) and maximum plasma concentration (cmax). Despite this high interindividual variability, the mean values obtained for AUC0-t and cmax after s.c. injection of rHuIFN gamma were approximately proportional to the dose administered: the injection of 0.1, 0.25 or 0.5 mg/m2 rHuIFN gamma resulted in AUC0-t values of 15.4, 31.5 or 69.6 ng h/ml, respectively and cmax was found to be 1.0, 2.4 and 4.9 ng/ml, respectively. With this s.c. administration protocol, objective antitumour responses were observed in two patients, but there was no partial or complete remission.

Adolescent↗

Functional criteria for staging and treatment of hairy cell leukemia.

The determination of clinical stage in hairy cell leukemia is hampered by the lack of common criteria. Furthermore, clinical stages in which the disease should be treated have not yet been defined. In this paper we propose common criteria for the clinical staging of all hairy cell leukemia patients (treated or untreated), as well as for the assessment of responses to therapy. These criteria are absence or presence of disease-related symptoms and disease progression. Based on these criteria we propose that hairy cell leukemia patients in the most favorable stage of the functional system, non-symptomatic Stable Disease (nsSD), do not require treatment. Only in patients with disease-related symptoms and/or signs of disease progression is treatment justified and necessary. No symmetry was observed between the functional stages and Jansen's stages. For evaluation of responses to treatment, our stages were more sensitive than the Leeds criteria. Experimental evidence enables the differentiation of patients with non-symptomatic stable disease from those with symptomatic and/or progressive disease.

Adult↗

Receptors for tumor necrosis factor on neoplastic B cells from chronic lymphocytic leukemia are expressed in vitro but not in vivo.

Recombinant tumor necrosis factor-alpha (TNF-alpha) is a cytokine that induces proliferation of neoplastic B cells from patients with chronic lymphocytic leukemia (CLL). To gain insight into the mechanisms involved in regulating TNF responsiveness, we have examined TNF receptor expression on neoplastic B-CLL cells. We have demonstrated that freshly isolated neoplastic B cells from patients with CLL did not express TNF receptors. After 1 day of incubation in culture medium, TNF receptors were detectable in the range of 540 to 1,500/cell. Kinetic experiments revealed that receptor expression was half-maximal after 3 hours of culturing and required de novo protein synthesis. The Scatchard plots of TNF-alpha binding indicated a single set of high-affinity TNF receptors with a dissociation constant of 70 pmol/L. TNF receptor expression in vitro was found in all examined cases. All cytokines tested, with the exception of IL-2, did not influence the expression of TNF receptors. The TNF receptor expression is enhanced in B-CLL cells cultured in the presence of interleukin-2 when compared with the receptor expression of cells cultured in medium alone. Our data suggest that neoplastic B-CLL cells in patients with stable disease do not express TNF receptors in vivo and that an unknown mechanism suppressing TNF receptor expression in vivo may play a role in growth regulation of neoplastic B cells.

B-Lymphocytes↗

Filter spot-ELISA for the enumeration of interferon-alpha antibody-secreting cells.

A filter spot-ELISA was developed for the enumeration of interferon-alpha (IFN-alpha) antibody secretion by murine and human cells. Various human IFN-alpha subtypes were coated onto nitrocellulose membranes by means of broad specificity bovine antibodies. Membranes were blocked with milk proteins, and antibodies released by individual cells during a 3 h culture period were visualized as distinct spots using peroxidase-conjugated, species-specific anti-immunoglobulin antibodies and diaminobenzidine/hydrogen peroxide substrate solution. The spot-ELISA is rapid, easy to perform, and highly sensitive. Possible applications include frequency estimates of IFN-alpha antibody-secreting cells in blood, tissues and hybridoma cultures as well as the evaluation of specificity and immunoglobulin class of the respective antibodies.

Animals↗

High-intensity therapy versus low-intensity therapy in advanced breast cancer patients.

The aim of this study was to evaluate the significance of response to the first two cycles of FEC (5-fluorouracil, 4-epirubicin, cyclophosphamide) in patients with advanced breast cancer. A total of 99 patients entered the study. They showed either high risk criteria and were previously untreated or showed low risk criteria and were pretreated by hormonal therapies. Eighty-two patients were evaluable. In 22 (27%) who had disease progression despite two cycles of FEC, further therapeutic attempts proved ineffective, the median survival being 2.8 months. The remaining patients responded either by stable disease (SD, n = 29; 35%), by partial or by complete remission (PR, CR, n = 31; 38%). These 60 patients were randomized to two regimes of maintenance therapy: FEC every 3 weeks or LMF (leukeran, methotrexate, 5-fluorouracil) every 6 weeks. The subsequent course of the disease was not different in both arms. It was neither influenced by the quality of early response, i.e. SD, PR, CR, nor by the intensity of chemotherapy. The prognostic impact of early response to two cycles of FEC proved to be higher than other prognostic parameters in the patients examined. Thus, early response may serve as a valid guide to adapt maintenance chemotherapy in individual patients with advanced breast cancer.

Adult↗

[Advantages and problems of interdisciplinary tumor conferences].

Interdisciplinary cancer conferences (ICC), which deal with the problems of individual patients, are an appropriate instrument for coordinating interdisciplinary decisions at an early stage and for ensuring adherence to standard diagnostic and therapeutic procedures. As shown by seven-years experience and data from 1225 cases, about 80% of the decisions made by the conference are followed by the responsible physician. Regular meetings at suitable times and locations, effective preparation with information about the problems to be discussed and rapid distribution of written reports to all participants will guarantee a continuing interest in presenting patients at the ICC.

Combined Modality Therapy↗

Tumor necrosis factor-alpha, but not lymphotoxin, stimulates growth of tumor cells in hairy cell leukemia.

We investigated the effect of recombinant tumor necrosis factor-alpha (rTNF-alpha) and recombinant lymphotoxin (rLT) in the growth modulation of purified hairy cell leukemia (HCL) cells. In response to rTNF-alpha, HCL cells from five of eight patients showed a 3 to 23-fold thymidine incorporation above their unstimulated controls. The effect was time and dose dependent with a maximum between 10 and 25 ng/ml rTNF-alpha after 120-hr incubation. rLT (1-50 ng/ml), however, could not enhance DNA synthesis in six of six cases. Cell number of rTNF-alpha stimulated cells ranged from 2-3 x 10(6)/ml from days 0-50 whereas cell number of unstimulated controls decreased from 3 x 10(6)/ml at day 0 to 0.01-0.02 x 10(6)/ml after 50 days in culture. rTNF-alpha induced proliferation could be suppressed in all HCL cell populations by 0.3 ng/ml recombinant interferon alpha (100 U/ml rIFN-alpha). TNF binding studies in two patients revealed that both TNF-sensitive HCL cells (1,990 +/- 148 receptors/cell) as well as TNF-insensitive HCL cells (1,261 +/- 101 receptors/cell) express specific receptors for TNF-alpha. These data show that rTNF-alpha and rLT have different effects on the growth of HCL cells. In addition there is a subgroup of patients who show no response to rLT or rTNF-alpha.

Adult↗

[Reversible germ cell toxicity following aggressive chemotherapy in patients with testicular tumors: results of a prospective study].

The impact of aggressive chemotherapy on reproductive and endocrine gonadal function was prospectively studied in 44 patients with germ cell tumors. Diagnostic procedures to determine gonadal toxicity consisted of hormone determinations, semen analyses, interviews with a standardized questionnaire, and gonadal histology. After chemotherapy all patients showed elevated serum levels of follicle-stimulating hormone (FSH) and azoospermia due to germ cell and stem cell loss. Recovery of spermatogenesis, as indicated by normalization of serum FSH levels and sperm density, occurred in 77% of the patients 25-60 months after cessation of chemotherapy. In all patients serum testosterone and luteinizing hormone (LH) values remained within normal limits after therapy indicating resistance of Leydig cells to cytotoxic drugs. Three patients fathered four healthy children after completion of chemotherapy. These data suggest significant reproductive dysfunction in all men treated for germ cell tumors. However, most patients showed late and complete recovery of spermatogenesis. In contrast, endocrine gonadal function was unaffected after chemotherapy in all patients. FSH and LH are feasible markers to assess drug-induced gonadal toxicity.

Adolescent↗

A phase I/II study of recombinant interferon alpha 2a and hydroxyurea for chronic myelocytic leukemia.

Nine previously untreated patients with Philadelphia chromosome-positive chronic myelocytic leukemia (CML) were treated with recombinant interferon alpha 2a (rIFN-alpha 2a) and hydroxyurea. Patients received 6 X 10(6) U rIFN-alpha 2a daily for the first week and 3 X 10(6) U rIFN-alpha 2a daily for the second week. As maintenance treatment starting on day 15, patients received 3 X 10(6) U rIFN-alpha 2a 3 times a week. Simultaneously, hydroxyurea was given, starting at a dose of 40 mg/kg on day one. The maintenance dosage was adjusted to the white blood cell count. Two patients responded with complete hematological remissions but without cytogenetic and molecular-genetic improvements. Seven patients responded with partial hematological remissions. Response to therapy was rapid; normal white blood cell counts were reached after a median of 12 days. The doses of rIFN-alpha 2a and hydroxyurea needed to keep the leucocyte count in the normal range were low (3 X 10(6) U rIFN-alpha 2a 3 times per week, 0.5-1.5 g hydroxyurea/day). Acute toxicity of the combination therapy consisted of fever (9 of 9 patients), flulike symptoms (7 of 9 patients), pruritus and/or rash (3 of 9 patients) and evidence of a tumor cell lysis syndrome (1 of 9 patients). The side effects were not dose-limiting. Combination therapy with rIFN-alpha 2a and hydroxyurea for CML is well tolerated and allows quick and effective hematological control of the disease.

Antineoplastic Combined Chemotherapy Protocols↗

Compliance of physicians and patients with a consensus protocol for treatment of advanced breast cancer.

In a multicenter study we used a consensus protocol including more than five subsequent therapeutic steps for treatment of patients with advanced breast cancer. A total of 335 evaluable patients from 27 participating hospitals were allocated to a low- or high-risk group, receiving different therapies during the initial phase of treatment. About half of these patients were treated without protocol violations (compliers). The protocol non-compliers were divided into three groups: those receiving more intensive therapy than recommended, those with similarly intensive, and those with less intensive therapy. The reasons for protocol violations were analysed. The intensity of the therapy given actually was correlated with the survival of subgroups. Median survival times were significantly longer in 208 low-risk than in 127 high-risk patients (P less than 0.0001), marginally longer in 165 compliers than in 170 non-compliers (P less than 0.04), significantly longer in low-risk compliers than in low-risk non-compliers (P = 0.002), and significantly shorter in high-risk compliers than in high-risk non-compliers (P = 0.007). Survival of all subgroups of low-risk non-compliers was the same regardless of the actual therapies given. The survival of high-risk patients who received less intensive therapy was significantly longer than that of high-risk compliers (P = 0.015). After six cycles of successful chemotherapy there was no difference, either in time to progression or in survival, between patients who had received either maintenance therapy or no therapy. We postulate that the groups of low-risk and high-risk patients comprised patients with different prognoses. Among low-risk patients, survival of the subgroup with poor prognosis (low-risk non-compliers) was not influenced by therapy. Among high-risk patients, a subgroup with poor prognosis may have been overtreated by using standard chemotherapies as recommended in our consensus protocol.

Breast Neoplasms↗