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P Siegenthaler

Publications and source records attributed to P Siegenthaler.

At least 19 recordsLinked to original sources
PubMed2004

The impact of tumour volume and surgery on the outcome of adults with supratentorial WHO grade II astrocytomas and oligoastrocytomas.

BACKGROUND: The study was performed to elucidate the impact of tumour volume and surgical resection on the long-term outcome of patients with supratentorial, diffuse, World Health Organization (WHO) grade II astrocytomas and oligo-astrocytomas. METHOD: After analysing 79 adult patients consecutively diagnosed between 1991 and 2000, we selected a group of 42 patients treated by surgery without adjuvant therapy. The tumour volume was defined as the whole region of T2-hyperintensity and measured interactively on pre- and postoperative and follow-up Magnetic Resonance Imaging (MRI) using a dedicated imaging software. Volumetric, clinical, and histological data were analysed for correlation with tumour progression (TP), malignant transformation (MT), drop in functional status (DKPS) and overall survival (OS). FINDINGS: Pre- and postoperative tumour volumes, and the involvement of more than one lobe were strongly associated with worse outcome. Preoperative tumour volume was the strongest predictor of OS (p<0.01) and the only predictor of MT (p<0.05). The absolute and relative volumes of tumour removed by surgery were not significantly associated with outcome. CONCLUSIONS. Initial tumour volume, measured as the volume of T2-hyperintensity on MRI, and tumour extension are the strongest predictors of outcome in patients with supratentorial diffuse astrocytic WHO Grade II tumours. The potential benefit of aggressive tumour resection needs to be investigated in a prospective controlled trial.

Adult↗
PubMed1998

Screening for urinary methadone by capillary electrophoretic immunoassays and confirmation by capillary electrophoresis-mass spectrometry.

This paper characterizes competitive binding, electrokinetic capillary-based immunoassays for urinary methadone using reagents which were commercialized for a fluorescence polarization immunoassay. After incubation of 25 microL urine with the reactants, a small aliquot of the mixture is applied onto a fused-silica capillary and the unbound fluorescein-labeled methadone tracer is monitored by capillary electrophoresis with on-column laser-induced fluorescence detection. Configurations in presence and absence of micelles were investigated, found to be capable of recognizing urinary methadone concentrations > or = 10 ng/mL, and shown to be suitable for rapid methadone screening of patient urines. Based upon shorter run times and a much better separation of free tracer and antibody-tracer complex, conditions without micelles are preferred. For confirmation analysis of urinary methadone and its major metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), capillary electrophoresis in a pH 4.6 ammonium acetate-acetic acid buffer was interphased to an atmospheric pressure ionization triple quadrupole mass spectrometry system. Using positive ion electrospray ionization and the tandem mass spectrometry mode with collision-induced dissociation in the collision cell, fragmentation of the two substances was determined. For confirmation via direct urine injection or application of a urinary extract, in-source fragmentation was employed and the first quadrupole was operated in the selected ion monitoring mode by switching between the masses of relevant precursor/product ion sets for methadone (m/z = 310, 265) and EDDP (m/z = 278, 249, 234). This capillary electrophoresis-mass spectrometry approach is shown to permit the confirmation of methadone and EDDP in patient urines that tested positive for methadone using electrokinetic capillary-based immunoassays, a fluorescence polarization immunoassay, and capillary electrophoresis with UV absorption detection.

Electrophoresis, Capillary↗
PubMed1997

Adjuvant chemotherapy in operable breast cancer: cyclophosphamide, methotrexate, and fluorouracil versus chlorambucil, methotrexate, and fluorouracil--11-year results of Swiss Group for Clinical Cancer Research trial SAKK 27/82.

PURPOSE: To compare two adjuvant combination chemotherapies, cyclophosphamide, methotrexate, and fluorouracil (CMF) and chlorambucil, methotrexate, and fluorouracil (LMF), for patients who had undergone potentially curative surgery for unilateral breast cancer, in terms of relapse, survival, and toxicity. PATIENTS AND METHODS: Selection criteria was as follows: stage pT1-3a, N+ or N-, M0, less than 72 years of age. Eligible patients were randomized to receive either CMF (cyclophosphamide 100 mg/m2 orally on days 1 to 14, methotrexate 40 mg/m2 intravenously (I.V.) on days 1 and 8, fluorouracil 600 mg/m2 I.V. on days 1 and 8) or LMF (Leukeran [Wellcome A.G., Bern, Switzerland] 5 mg/m2 orally on days 1 to 14 with the some I.V. cytostatic drugs). Follow-up examinations were performed every 3 months during the first 3 years after mastectomy, and every 6 months thereafter. RESULTS: A total of 246 patients were randomized, of whom 232 who were fully eligible and contribute to the analyses presented here. No statistically significant difference in favor of adjuvant CMF over LMF emerges after a median follow-up duration of 11.2 years, for either overall survival (P = .15) or disease-free survival (P = .14). A consistent trend suggestive of a possible relative benefit associated with CMF should be pointed out. However, CMF presents a significantly worse toxicity profile as concerns hematologic parameters as well as alopecia, nausea, and vomiting. CONCLUSION: This prospective trial has not identified a statistically significant difference in disease-free survival or overall survival between the two adjuvant regimens LMF and CMF. Although a trend in favor of CMF has been observed in premenopausal patients, this has to be weighted against its definitely more pronounced toxicity profile.

Adult↗
PubMed1995

Phase II trial of CPT-11 in patients with advanced pancreatic cancer, an EORTC early clinical trials group study.

BACKGROUND: CPT-11 (irinotecan) is a semi-synthetic derivative of camptothecin and exerts its activity by inhibiting DNA topoisomerase I. A phase II study of this drug was performed in patients with pancreatic cancer. PATIENTS AND METHODS: Eligibility criteria included advanced non-chemotherapy-pretreated pancreatic cancer. CPT-11 was administered as a 30-minute i.v. infusion at a dose of 350 mg/m2 diluted in 250 ml normal saline every 3 weeks. RESULTS: Thirty-four eligible patients were enrolled in the study, thirty-two of them were evaluated, and three achieved partial responses (9%; 95% C.I. = 3%-25%). The duration of response was 7.2, 7.5 and 7.8 months, respectively. Thirteen patients had no change, fourteen patients had progressive disease and two had early progressive disease. The median duration of survival for all patients treated was 5.2 months. The main toxicities (CTC grade > or = 3) were diarrhea, leukocytopenia, asthenia, nausea and vomiting in, respectively, 7%, 16%, 8%, 6%, 4% of the courses. These toxicities were reversible and manageable with anti-emetics and prophylactic or curative antidiarrheal agents. CONCLUSION: CPT-11 is an interesting moderately effective drug in pancreatic cancer.

Adult↗
PubMed1995

Early versus late alternating chemotherapy in small-cell lung cancer. Swiss Group for Clinical Cancer Research (SAKK).

BACKGROUND: From 1984 to 1989, the Swiss Group for Clinical Cancer Research (SAKK) performed a randomized phase III trial comparing early versus late alternating chemotherapy in patients with small-cell lung cancer. PATIENTS AND METHODS: 406 eligible patients were entered into the trial. Regimen A consisted of PAV (cisPlatin, Adriamycin, VP 16-213, and Regimen B of CyMOC (Cyclophosphamide, Methotrexate, Oncovin, CCNU). Cycles were repeated as rapidly as possible. patients were randomized to receive either ABABAB (early alternating chemotherapy) or AAABBB (late alternating chemotherapy). After six cycles patients with limited disease in complete or partial remission and those with extensive disease in complete remission received irradiation to the primary (45 Gy) and the CNS (36 Gy). RESULTS: The overall remission rate was 87% with 31% complete remissions. The median survival of all 406 eligible patients was 346 days with 15% of the patients alive at two years. The overall remission rate, the rate of complete remission, the median survival and the rate of long-term survival were not significantly different in the two treatment arms. In limited disease the estimated percentages of survival at 2 years were 33% in the early and 24% in the late alternating chemotherapy arms. Patients with extensive disease survived significantly longer with late alternating chemotherapy than on the early alternation regimen (median survival 336 days versus 301 days, p = 0.01). In the latter patients the received dose intensities (RDI) of cisplatin, adriamycin and etoposide were significantly higher in the late-alternation arm. Patients treated with early alternating chemotherapy rated their tumor symptoms, functional states, fatigue/malaise and restriction of social activity significantly better, reflecting an improved subjective adjustment. CONCLUSIONS: Alternating chemotherapy with PAV-CyMOC plus consolidating radiotherapy is a feasible and effective treatment for small-cell lung cancer, with acceptable toxicity. Whereas patients with early alternating chemotherapy achieve a better subjective adjustment, late alternating chemotherapy allows for a higher RDI of cisplatin, adriamycin and etoposide, which results in a significantly longer median survival of patients with extensive disease.

Actuarial Analysis↗
PubMed1994

Phase II trial of anaxirone (TGU) in advanced colorectal cancer: an EORTC Early Clinical Trials Group (ECTG) study.

Anaxirone, a rationally synthesised triepoxide derivative, was given to 46 patients with metastatic colorectal cancer. Good risk patients received 800 mg/m2 as a rapid intravenous injection every 4 weeks, whereas poor risk patients received 650 mg/m2. Of 46 patients, 45 were evaluable for toxicity and 42 for efficacy analysis. There were 37/45 patients with poor risk, showing no difference in toxicity as compared to good risk patients. The major toxic effect was myelosuppression with 34% of all patients experiencing grade 3 or 4 leucopenia; thrombocytopenia was less frequent. Locoregional phlebitis occurred in 66% of the patients. There was no objective tumour response to anaxirone in 42 evaluable patients. Only 4 patients achieved stabilisation of the disease lasting maximally up to 248 days. Anaxirone is inactive in metastatic colorectal cancer.

Adult↗
PubMed1994

Combined-modality treatment of small-cell lung cancer: randomized comparison of three induction chemotherapies followed by maintenance chemotherapy with or without radiotherapy to the chest. Swiss Group for Clinical Cancer Research (SAKK).

BACKGROUND: From 1980 to 1983 the Swiss Group for Clinical Cancer Research (SAKK) performed a randomised phase III trial in patients with small-cell lung cancer with the objective of improving the results of induction chemotherapy and defining the role of consolidating chest irradiation. PATIENTS AND METHODS: Patients were initially randomised to induction arms AVP (adriamycin, etoposide and cisplatin given every four weeks for four cycles), EVA (cyclophosphamide, etoposide and adriamycin given every four weeks for four cycles) or MOC/AVP (methotrexate, vincristine, cyclophosphamide alternating with adriamycin, etoposide and cisplatin given for two cycles). All patients received prophylactic cranial irradiation with 30 Gy, and after four months of induction chemotherapy were randomized to maintenance chemotherapy with or without consolidating chest irradiation. The patients in the combined-modality maintenance arm first received radiation therapy to the chest (45 Gy) followed by MOC/EVA chemotherapy. RESULTS: 266 patients were eligible and evaluable. An overall response rate of 70% with 21% of complete remissions, a median survival of 9.3 months and survival of 8% of the patients at two years were observed. The highest objective response rate was achieved with the AVP-induction chemotherapy with an 80% response rate and 32% complete remissions. Similar results were achieved with the alternating regimen of MOC/AVP. In contrast, patients treated with the EVA induction regimen had significantly lower overall remission (56%) and complete remission rates (7%). The role of consolidating chest irradiation could not be clarified in limited-disease patients due to the small number of them who were randomised to the maintenance part of the study. However, in patients with extensive disease in partial remission after induction treatment, combined maintenance therapy had a more significant adverse effect on survival than maintenance chemotherapy alone (median survival in the maintenance phase of 148 days versus 239 days, p = 0.011). CONCLUSION: We conclude that the combination of adriamycin, etoposide and cisplatin is an active induction treatment. Consolidating chest irradiation is contraindicated in patients with extensive disease in partial remission after induction when given in a sequential manner, as in our trial.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Combination chemotherapy with mitomycin, vindesine, and cisplatin for non-small cell lung cancer. Association of antitumor activity with initial tumor burden and treatment center.

From 1984 through 1986, 205 patients with non-small cell lung cancer were entered into a group-wide trial of the Swiss Group for Clinical Cancer Research (SAKK). This trial evaluated the combination of mitomycin (8 mg/m2 intravenously [IV] on day 1), vindesine (3 mg/m2 IV on days 1 and 8), and cisplatin (60 mg/m2 IV on day 1) with forced diuresis, repeated every 4 weeks (MiViP regimen). One hundred eighty-three patients were evaluable. Six complete and 69 partial responses were documented for an overall response rate of 41% (95% confidence interval, 34% to 50%). In the multivariate analysis the strongest predictors for response were the participating institution and the number of initially involved organ sites. The estimated median time to progression for patients with a complete response, partial response, or stable disease was 155 days (estimated inter-quartile range, 99 to 258 days). In the multivariate analysis the time to progression was significantly associated with the number of involved organ sites (P = 0.041). The estimated median survival time for the 183 evaluable patients was 239 days (estimated inter-quartile range, 137 to 436 days). In univariate and multivariate analyses performance status, number of involved organ sites, pretreatment status with radiation therapy, and participating institution were all significantly associated with survival. The principal toxicities were myelosuppression and nausea and vomiting with 16% of the patients refusing further treatment after a median of four cycles of chemotherapy. In conclusion, the MiViP regimen was an active combination chemotherapy in patients with non-small cell lung cancer in a large trial performed by the SAKK. The prognostic value of the participating institution and the number of organ sites involved by metastatic deposits in non-small cell lung cancer needs further investigation.

Adult↗
PubMed1988

Phase II study of iproplatin (CHIP, JM-9) in advanced testicular cancers progressing after prior chemotherapy.

Twenty-two patients with advanced testicular cancer received iproplatin at a dose of 180-240 mg/m2 every 4 weeks. All the patients progressed or recurred after chemotherapy including cisplatin. The most severe toxicity was thrombocytopenia with two toxic deaths after a first cycle of 240 and 180 mg/m2 respectively. Nausea and vomiting were almost universal but mild in intensity. One renal failure occurred 6 weeks after the first cycle while the tumor was progressing. No antitumor activity was observed in this heavily pretreated population of patients.

Adult↗
PubMed1986

Phase II trial of nimustine (ACNU; 3-[4-amino-2-methyl-5-pyrimidinyl) methyl]-1-(2-chloroethyl)-1-nitrosourea hydrochloride) in patients with small cell carcinoma of the lung after failure on combination chemotherapy.

Thirty-nine previously treated patients received Nimustine in a phase II trial to test the therapeutic activity in refractory small cell lung cancer. Nimustine was given as a direct i.v. injection of 100 mg/m2 with treatments repeated every six weeks. Three partial remissions of 56, 123 and 355 days duration were noted among 34 evaluable patients. Thrombocytopenia was prominent with a median platelet nadir of 47,000/microliter. We conclude that Nimustine has minor antitumor-activity in heavily pretreated patients with small cell lung cancer. The definitive value of Nimustine in the treatment of small cell lung cancer, as well as its superiority over its parent compounds remains to be established.

Aged↗
PubMed1986

Phase II study of 5'-deoxy-5-fluorouridine (doxifluridine) in advanced malignant melanoma.

Forty-two patients with malignant melanoma were treated with doxifluridine, 4000 mg/m2 daily X 5, repeated every 3 weeks. The daily dose was reduced to 3000 mg/m2 in patients who had experienced severe myelosuppression with prior chemotherapy. A total of 35 patients were evaluable for response, and 25 of these received two or more courses. Two responses were observed. Toxicity mainly took the form of nausea, vomiting, stomatitis, dizziness, ataxia, and fatigue. Mild leukopenia was frequent (43%). Nadir counts less than 1.5 X 10(9)/l leukocytes or 50 X 10(9)/l platelets were seen in 7% and 2% of the courses respectively. Doxifluridine has no useful activity against malignant melanoma.

Drug Evaluation↗
PubMed1984

Phase II study of 9-hydroxy-2N-methylellipticinium acetate.

A broad phase II trial of elliptinium was conducted in 105 evaluable patients with advanced solid tumors. The drug was given as a 60-90-min i.v. infusion at a weekly dose of 100 mg/m2. Of 36 breast cancer patients, one achieved complete and six achieved partial response for an overall response rate of 19%. Responses lasted for 12-56 weeks from initiation of therapy. There was also one partial response among 21 patients with squamous cell carcinoma of the lung. No response could be obtained in 17 patients with colon cancer, 13 patients with head and neck cancer and 18 patients with a wide variety of other malignancies. Myelosuppression was minimal. Nausea and vomiting were the most frequent toxic effects. The drug also produced serious xerostomia and acute intravascular hemolysis. Asthenia was common. Other adverse reactions included fever and chills, transient neurologic and cardiovascular manifestations and renal function impairment. Additional work is needed to define optimal modes of drug administration.

Adult↗