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N Niederle

Publications and source records attributed to N Niederle.

At least 55 records · Page 3Linked to original sources
PubMed1992

[Neuroendocrine tumors of the gastrointestinal tract. Part 2: Current therapeutic concepts].

When diagnosed, the greater proportion of functioning endocrine tumors have already metastasized. As a result, the primary aim of treatment--complete surgical removal of the growth--is possible in only a small number of patients. This gives considerable importance to palliative treatment. Interferons and somatostatin are the substances in the forefront of therapeutic interest today, cytostatic chemotherapy having proved largely ineffective and associated with considerable side effects. A feature common to interferons and somatostatin is the fact that they are much more likely to achieve a subjective improvement in clinical symptoms rather than objective remission. However, this is not disadvantage, since, in view of the slow growth of these tumors, quality of life is determined by controlling endocrine activity and not by debulking tumor mass.

Carcinoid Tumor↗
PubMed1992

[Neuroendocrine tumors of the gastrointestinal tract. 1: Clinical aspects].

Endocrine cells are characterized by common biochemical properties and specific cellular markers. Endocrine tumors, too, differ from other types of tumor in a number of ways. These have to do with the classification, the occurrence of functioning or nonfunctioning forms, benign and malignant courses, solitary or multiple presentation, as well as entopic and ectopic growth forms. The incidence of the gastrointestinal functioning tumors is about 0.5-1.0 per 100,000, the nonfunctioning tumors predominating many times over. The diagnosis of functioning endocrine tumors in the early phases of the disease is based on the biochemical demonstration of substances released into the blood, and the clinical picture is determined not primarily by the size or extent of the tumor, but by the biological effects of the tumor secretions. The clinical symptomatology associated with these tumors is often much more marked than the measurable tumor manifestation.

Carcinoid Tumor↗
PubMed1992

Clonogenic assay is not predictive but reflects therapeutic efficacy of interferons in the treatment of chronic myelogenous leukemia.

Patients with chronic myelogenous leukemia (CML) have been treated with interferon (IFN) alpha-2b alone or in combination with IFN gamma. In order to predict clinical response to IFN, bone marrow samples from 15 CML patients were incubated with serial dilutions of IFN alpha-2b to obtain the IC50 values for erythroid burst forming units (BFU-E) and granulocyte-macrophage colony forming units (CFU-GM). A dose-dependent inhibition of at least one lineage was observed in all but one sample. An inhibitory effect of greater than 50% was reached for BFU-E in 8/14 patients and for CFU-GM in 10/14 patients. All three patients with no response (NR) to IFN treatment had IFN-sensitive BFU-E and CFU-GM. In four patients with hematologic remission (HR) or partial hematologic remission (PHR), BFU-E or CFU-GM were affected very little by the inhibitory effect of IFN. These observations suggest no predictive value for pretesting IFN sensitivity in vitro. The in vivo effect of IFN on the hemopoietic progenitor cells BFU-E and CFU-GM was evaluated in patients treated with either IFN alpha-2b alone (n = 11), or in combination with low dose IFN gamma (n = 10). All patients were newly diagnosed and not pretreated. After a median treatment duration of 11 months (range 3-25) a significant decrease in BFU-E and CFU-GM was observed in both groups of patients. We conclude that in vitro colony growth reflects the therapeutic efficacy of IFN.

Adult↗
PubMed1992

Relation between leukocyte counts and cortisol secretion in CML patients undergoing combined TNF alpha/IFN alpha therapy.

During long-term interferon alpha-2b (IFN) therapy of Philadelphia chromosome-positive chronic myelogenous leukemia (CML) patients, short-term effects of tumor necrosis factor alpha (TNF) on peripheral leukocyte counts, as well as cortisol and corticotropin (ACTH) release were studied. TNF (40-160 micrograms/m2) was given as a 2-h infusion on 5 consecutive days every 3 weeks, in addition to s.c. daily IFN injections (4 mio U/m2), to four (two male/two female) patients, who had been treated for more than 8 months with IFN and additionally for 0-7 months with TNF. Leukocyte counts, cortisol, and ACTH were determined at 30-min intervals between 4 p.m. and midnight. Profiles were determined the day before and on day 1 of TNF therapy. Leukocyte numbers decreased 30 min after start of TNF administration and increased 30-60 min later with a rebound until the next TNF application. The increase of leukocyte counts was due mostly to neutrophil granulocytes. ACTH levels increased 30 min, cortisol 60 min, and leukocyte counts 90 min after start of TNF infusion. Metopirone, an inhibitor of cortisol synthesis given to one patient, suppressed the TNF-induced stimulation of cortisol secretion and subsequent increase of leukocyte counts, while ACTH blood levels were enhanced. It was concluded that leukocyte count increases after TNF/IFN administration might be related to TNF-evoked cortisol secretion.

Adrenocorticotropic Hormone↗
PubMed1992

The concept of dose intensification in the treatment of neoplastic disease.

This paper summarizes different theoretical and clinical approaches contributing to the concept of dose intensification. According to this concept, the amount of antineoplastic drug delivered per time predominantly determines the clinical outcome in patients with neoplastic disease. With the availability of recombinant haemopoietic growth factors haematotoxic side effects might be reduced, making this concept more feasible for clinical use. However, more prospective randomized studies, in which dose-intensity is the only treatment variable, are needed to prove that dose intensification will lead to higher survival rates.

Antineoplastic Agents↗
PubMed1992

Tumor necrosis factor alpha modifies resistance to interferon alpha in vivo: first clinical data.

Patients with Philadelphia-positive chronic-phase chronic myelogenous leukemia (CML) resistant to interferon (IFN) alpha were treated in a phase I/II study with recombinant human tumor necrosis factor alpha to overcome IFN alpha resistance. Doses of 40, 80, 120 or 160 micrograms/m2 TNF alpha were given as 2-h infusions on 5 consecutive days every 3 weeks. IFN alpha (4 x 10(6) IU/m2 s.c., daily) treatment was continued. Six patients were treated, completing 1-24 (median, 12) treatment cycles. Five of the six patients achieved partial hematological remission, while the remaining patient had to stop treatment because of WHO grade 4 thrombocytopenia following the first TNF alpha cycle. No complete hematologic remission or cytogenetic improvement was seen. Side-effects were similar to those described for both substances alone. Maximum tolerable TNF doses usually varied between 80 micrograms/m2 and 160 micrograms/m2. To examine possible pathways of TNF activity in these patients, interferon receptor status and (2'-5')-oligoadenylate synthetase levels were examined in peripheral blood mononuclear cells. Both parameters remained unchanged during TNF alpha treatment. These preliminary data point to significant clinical efficacy of additionally applied TNF alpha in IFN alpha-resistant CML patients.

2',5'-Oligoadenylate Synthetase↗
PubMed1992

Lupus-like autoimmune disease induced by interferon therapy for myeloproliferative disorders.

Symptoms of autoimmune disease were evaluated in 125 patients with chronic myelogenous leukemia (CML) and in 12 patients with essential thrombocythemia undergoing treatment with recombinant interferon (IFN)-alpha-2b plus/minus low-dose recombinant IFN-gamma. Twenty-seven of 137 patients (20%) developed rheumatoid symptoms. Furthermore, the incidence of antinuclear antibody (ANA) formation was studied. Elevated ANA titers were found in 5/19 (26%) of CML patients at the time of diagnosis and in 3/18 (17%) of patients treated with hydroxyurea or busulfan. During IFN treatment, 18 of 25 tested patients (72%) had elevated ANA titers. In 15 of these ANA-positive patients, clinical signs of autoimmune disease appeared. All these patients were under long-term IFN treatment and were in remission of disease. In three patients criteria for systemic lupus erythematosus were fulfilled. Severity of side effects had led to the discontinuation of IFN treatment in these patients. The data indicate that IFN-alpha and IFN-gamma can induce ANA associated with autoimmune disease in patients with myeloproliferative disorders.

Adult↗
PubMed1992

No correlation between site of breakpoint in the BCR gene and platelet counts in Philadelphia chromosome-positive CML.

In chronic myelogenous leukemia (CML) malignant cells are characterised by the Philadelphia chromosome (Ph), resulting from a translocation t(9;22). The position of the breakpoint within the major breakpoint cluster region (M-bcr) on chromosome 22 has been shown to correlate with the clinical course of the disease or, more recently, thrombopoietic activity. We have therefore determined the breakpoint localisation in 53 Ph-positive CML patients. Following the 5'/3'-region definition of Inokuchi et al. Leukemia Research 15, 1067 (1991) [1], 22 of our patients have 5' and 31 of our patients have 3' orientated breaks. No correlation was found between platelet counts and breakpoint localisation.

Chromosome Aberrations↗
PubMed1992

Opposite sensitivity to the antiproliferative action of interferon-alpha and granulocyte-macrophage colony-stimulating factor in monoblastic U937 cells.

Three variants of the human monoblastic cell line U937 with different degrees of sensitivity to the antiproliferative action of interferon-alpha (IFN-alpha were examined for phenotypic differences. The highly IFN-sensitive variant U937-V expressed twice as many IFN-alpha binding sites as both its IFN-alpha-resistant derivative U937-VR and the cell line U937 exhibiting a 20-fold reduction in IFN-alpha sensitivity as compared to U937-V cells. All three variants were IFN-reactive with regard to induction of 2',5'-oligoadenylate (2-5A) synthetase activity and were similarly sensitive to the growth-inhibiting action of IFN-gamma and tumor necrosis factor. Responsiveness to the antiproliferative effect of granulocyte-macrophage colony-stimulating factor (GM-CSF), however, was confined to cell lines U937 and U937-VR. Although expressing a comparable number of GM-CSF receptors, the highly IFN-sensitive variant U937-V was refractory to GM-CSF. Flow cytometry revealed a marked difference in the expression of the antigen CD11b which was detectable on 85% of cells of the U937-V line but only on approximately 25% of cells derived from the U937 and U937-VR lines. Results thus demonstrate opposite sensitivity of U937 cells to the growth-inhibiting action of IFN-alpha and GM-CSF, apparently dependent on the state of U937 differentiation as determined by expression of the CD11b antigen.

2',5'-Oligoadenylate Synthetase↗
PubMed1992

Treatment of high-risk, nonseminomatous testicular cancer with cisplatin, ifosfamide and bleomycin: long-term results.

Thirty-four patients with stage IIC (unresectable, retroperitoneal tumor mass (RTM) greater than 5 cm), stage IVC (minimal lung metastases less than 10 cm3 and RTM greater than 5 cm) and IVD (lung metastases greater than 10 cm3 and RTM greater than 5 cm), who had not received previous chemotherapy, were treated with cisplatin (40 mg/m2, on days 2-4), ifosfamide (5 g/m2, on days 1 and 5) and bleomycin (30 mg, on days 1, 8, 15) (PIB), every 21 days. Twenty of the 34 patients (59%) achieved a complete remission (CR). Furthermore, five patients (15%) showed no evidence of disease (NED) after surgical removal of residual tumor masses (NED rate of 74%). A tumor marker-negative partial remission (PR) occurred in 3/34 patients (9%), and a tumor marker-positive PR in another 3/34 patients (9%). Three patients did not respond to this regimen. At a median follow-up period of 38 months (range, 15-47 months), 26/34 patients (76%) were alive, 21 (62%) of them without evidence of disease and three with a stable tumor marker-negative remission. Major toxicity consisted of myelosuppression, neurotoxicity and nephrotoxicity. Chemotherapy-related mortality occurred in two patients (one septicemia and one bleomycin-induced lung fibrosis). In conclusion, PIB is an effective induction regimen in patients with high-risk NSTC. However, controlled clinical trials are necessary to prove the superiority of dose intensification schedules.

Adult↗
PubMed1992

Combination therapy with interferon alpha-2b plus low-dose interferon gamma in pretreated patients with Ph-positive chronic myelogenous leukaemia.

Between March 1988 and July 1990, 28 adults with chronic myelogenous leukaemia (CML) were treated with a combination of recombinant human interferon (IFN) alpha-2b s.c. (initial dose 4 x 10(6) U/m2) and recombinant human IFN gamma s.c. (50 micrograms totally) daily. All patients were in chronic phase disease and had been treated previously with chemotherapy or bone marrow transplantation. A complete haematologic remission was achieved in three patients (11%), a haematologic remission in 12 patients (43%), and a partial haematologic remission in seven patients (25%). Six patients did not respond to this schedule. Acute side-effects were flu-like symptoms, fever and chills. During long-term treatment six patients developed polyarthralgia. Haematotoxicity WHO grade III occurred in three patients, and WHO grade IV in two patients. One patient developed psychosis, and in another patient an exacerbation of a pre-existing sarcoidosis was observed. We conclude that this combination is tolerable and effective in inducing haematological remissions in pretreated CML patients.

Adolescent↗
PubMed1992

A prospective randomized comparison of single-agent interferon (IFN)-alpha with the combination of IFN-alpha and low-dose IFN-gamma in chronic myelogenous leukaemia.

In patients with previously untreated chronic myelogenous leukaemia (CML) the efficacy of single-agent interferon (IFN)-alpha at an initial dose of 4 x 10(6) U/m2 (arm A) was compared with the combined administration of the identical dose IFN-alpha plus a total dose of 50 micrograms IFN-gamma (arm B). 51 patients entered this study between April 1987 and October 1989; the analysis was performed in March 1991 and was focused on response rates and toxicity. 54% of patients on arm A and 56% of arm B patients attained haematologic remission. 29% of patients on arm A and 24% of arm B patients had partial haematologic remission. A decrease in Philadelphia chromosome (Ph)-positive metaphases of more than 10% was only seen in patients who had achieved complete haematologic normalization. In 21% of patients on arm A and 20% of arm B patients, the percentage of Ph-positive cells declined to less than 35%. Toxicity was different between the two study groups with more pronounced hepatotoxicity observed in patients treated with IFN-alpha alone. Among the patients receiving both IFNs, alpha and gamma, there were 2 fatal infectious complications. This serious toxicity in conjunction with lack of a clinically meaningful difference between the two treatment schedules has led us to terminate the study. In conclusion, the addition of low-dose IFN-gamma failed to improve the efficacy of IFN-alpha in this study.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Ifosfamide in non-small cell lung cancer: a review.

In recent years, ifosfamide has proven to be one of the most effective cytostatic drugs in the treatment of non-small cell lung cancer. Single-agent studies have demonstrated response rates of 15% to 30%. Combinations containing ifosfamide together with one or two other cytostatic agents yield overall response rates of 30% to 45%, with 5% to 10% complete remissions. For this purpose, ifosfamide has proven to be an ideal constituent, especially since the routine use of mesna uroprotection has significantly reduced its toxicity. As myelosuppression is now the primary dose-limiting toxicity, further investigations are directed toward the question of whether adjuvant administration of hematopoietic growth factors can improve treatment results by allowing increased dose intensity. This seems to be particularly important in patients with malignancies that respond poorly to cytostatic chemotherapy to determine whether survival can be significantly prolonged. Further studies with ifosfamide, moreover, should include neoadjuvant investigations in patients with stages II and III disease or its combination with other treatment modalities.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Induction of 2'-5' oligoadenylate synthetase during interferon treatment of chronic myelogenous leukemia.

Activity of the interferon-induced enzyme 2'-5' oligoadenylate synthetase (2-5 OAS) was measured in peripheral blood mononuclear cells (PBMCs) and serum of patients with chronic phase Ph'-positive chronic myelogenous leukemia (CML) treated with interferon-alpha (IFN-alpha) (4 x 10(6) IU/m2) alone or in combination with 50 micrograms IFN-gamma. At the beginning of IFN therapy, marked elevation of 2-5 OAS titers was detected in PBMCs (pretreatment 0.03-1.62, median 0.2; during treatment 0.8-13.14, median 4.31; 22 patients studied) and in serum (pretreatment 21-156 pmol/dl, median 62; during treatment 532-1740 pmol/dl, median 800; eight patients studied). However, 2-5 OAS titers were not related to clinical outcome or IFN therapy and also during IFN resistance elevated 2-5 OAS activity in PBMCs (median 3.45; range 1.05-13.14; 11 patients studied) were detected. These data argue against direct involvement of the 2-5 OAS system in the therapeutic effect of IFN in CML. However, 2-5 OAS titers in PBMCs or serum appear to be a reliable control of biologically active IFN therapy.

2',5'-Oligoadenylate Synthetase↗
PubMed1992

Treatment of chronic myelogenous leukemia with different cytokines.

In vitro data suggest a synergistic antiproliferative effect of different cytokines. In four clinical studies chronic myelogenous leukemia (CML) patients were treated with interferon (IFN)-alpha alone or IFN-alpha combined with either low-dose IFN-gamma or tumor necrosis factor (TNF)-alpha. The best response was achieved in previously untreated patients with good prognostic factors and highest tolerable IFN dose for maintenance treatment. Breakpoint localization within the major breakpoint cluster region did not correlate with response to IFN. In a randomized study of IFN-alpha versus IFN-alpha combined with IFN-gamma, no differences in response rates were observed. Patients with primary or secondary resistance to these treatment modalities received a combination therapy with IFN-alpha and TNF-alpha. In these patients, a decrease in leukocyte counts was noted, but no cytogenetic improvement occurred.

Adult↗
PubMed1991

Minimal residual disease in patients with chronic myelogenous leukemia undergoing long-term treatment with recombinant interferon alpha-2b alone or in combination with interferon gamma.

Interferon (IFN) therapy has become widely used for the treatment of chronic myelogenous leukemia. Hematologic remissions can be induced in about 60% of patients. Moreover, in a small number of patients loss of the Philadelphia (Ph) chromosome and of the BCR-ABL rearrangement is observed. We have used genomic Southern blotting as well as a two-step polymerase chain reaction (PCR) method to score for BCR-ABL messenger RNA (mRNA) in patients with hematologic remission induced by treatment with IFN alpha-2b alone or in combination with IFN gamma. Concomitantly, cytogenetic analysis was performed. In 11 of 115 patients reported here, a complete loss of rearranged BCR fragments was observed in Southern blots of peripheral blood (PB) and/or bone marrow (BM) cell samples. Malignant marker bands disappeared first in the PB. In six patients, this genotype remained stable, whereas in five patients, low-intensity, rearranged bands reappeared despite continuation of treatment. The reappearance of the malignant marker was not accompanied by a clinical relapse. Ph-negative metaphases were observed in PB cells of four patients and in the PB and BM cells of two of these patients. In the samples of the other patients, residual Ph-positive cells were detected. By two-step PCR, residual BCR-ABL rearranged transcripts were found in samples of 10 patients.

Adult↗