Baard-Christian Schem
University of Bergen
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Lancet Oncology | 2010
Rolf D. Issels; Lars H. Lindner; Jaap Verweij; Peter Wust; Peter Reichardt; Baard-Christian Schem; S. Abdel-Rahman; Soeren Daugaard; Christoph Salat; Clemens-Martin Wendtner; Zeljko Vujaskovic; R. Wessalowski; Karl-Walter Jauch; Hans Roland Dürr; Ferdinand Ploner; Andrea Baur-Melnyk; Ulrich Mansmann; Wolfgang Hiddemann; Jean-Yves Blay; Peter Hohenberger
BACKGROUND The optimum treatment for high-risk soft-tissue sarcoma (STS) in adults is unclear. Regional hyperthermia concentrates the action of chemotherapy within the heated tumour region. Phase 2 studies have shown that chemotherapy with regional hyperthermia improves local control compared with chemotherapy alone. We designed a parallel-group randomised controlled trial to assess the safety and efficacy of regional hyperthermia with chemotherapy. METHODS Patients were recruited to the trial between July 21, 1997, and November 30, 2006, at nine centres in Europe and North America. Patients with localised high-risk STS (> or = 5 cm, Fédération Nationale des Centres de Lutte Contre le Cancer [FNCLCC] grade 2 or 3, deep to the fascia) were randomly assigned to receive either neo-adjuvant chemotherapy consisting of etoposide, ifosfamide, and doxorubicin (EIA) alone, or combined with regional hyperthermia (EIA plus regional hyperthermia) in addition to local therapy. Local progression-free survival (LPFS) was the primary endpoint. Efficacy analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT 00003052. FINDINGS 341 patients were enrolled, with 169 randomly assigned to EIA plus regional hyperthermia and 172 to EIA alone. All patients were included in the analysis of the primary endpoint, and 332 patients who received at least one cycle of chemotherapy were included in the safety analysis. After a median follow-up of 34 months (IQR 20-67), 132 patients had local progression (56 EIA plus regional hyperthermia vs 76 EIA). Patients were more likely to experience local progression or death in the EIA-alone group compared with the EIA plus regional hyperthermia group (relative hazard [RH] 0.58, 95% CI 0.41-0.83; p=0.003), with an absolute difference in LPFS at 2 years of 15% (95% CI 6-26; 76% EIA plus regional hyperthermia vs 61% EIA). For disease-free survival the relative hazard was 0.70 (95% CI 0.54-0.92, p=0.011) for EIA plus regional hyperthermia compared with EIA alone. The treatment response rate in the group that received regional hyperthermia was 28.8%, compared with 12.7% in the group who received chemotherapy alone (p=0.002). In a pre-specified per-protocol analysis of patients who completed EIA plus regional hyperthermia induction therapy compared with those who completed EIA alone, overall survival was better in the combined therapy group (HR 0.66, 95% CI 0.45-0.98, p=0.038). Leucopenia (grade 3 or 4) was more frequent in the EIA plus regional hyperthermia group compared with the EIA-alone group (128 of 165 vs 106 of 167, p=0.005). Hyperthermia-related adverse events were pain, bolus pressure, and skin burn, which were mild to moderate in 66 (40.5%), 43 (26.4%), and 29 patients (17.8%), and severe in seven (4.3%), eight (4.9%), and one patient (0.6%), respectively. Two deaths were attributable to treatment in the combined treatment group, and one death was attributable to treatment in the EIA-alone group. INTERPRETATION To our knowledge, this is the first randomised phase 3 trial to show that regional hyperthermia increases the benefit of chemotherapy. Adding regional hyperthermia to chemotherapy is a new effective treatment strategy for patients with high-risk STS, including STS with an abdominal or retroperitoneal location. FUNDING Deutsche Krebshilfe, Helmholtz Association (HGF), European Organisation of Research and Treatment of Cancer (EORTC), European Society for Hyperthermic Oncology (ESHO), and US National Institute of Health (NIH).
Journal of Neuro-oncology | 1990
Olav Mella; Rolf Bjerkvig; Baard-Christian Schem; Olav Dahl; Ole Didrik Laerum
Anin vivo glioma model was developed in syngeneic BD IX rats. The BT4An tumor was derived from serialin vivo passages of the BT4A tumor, originally induced from transformed fetal rat brain cells after transplacental exposure to ethylnitrosourea. The cell line was characterized for the presence of neuroglial differentiation markers, chromosome content and cell cycle distribution as determined by flowcytometry. A standardized method for i.c. tumor induction was developed, and the tumors were investigated by light and electron microscopy and for evidence of blood-brain barrier disruption. Tumor cell ability for phagocytosis was studied, as this property may be important for the invasion pattern of the tumors.We conclude that the model seems suitable for bothin vivo therapy and invasion studies. The tumor had 100% tumor take, yielded a predictable symptom-free life span after inoculation, had a characteristic histological picture of an aggressive glioma, and the blood-brain barrier within the tumor was in part disrupted. Compared to the parent cell line, there was loss of neuroglial differentiation markers, the chromosomal distribution was changed, and the ability for phagocytosis was practically lost.
International Journal of Radiation Oncology Biology Physics | 2000
Hans Petter Eikesdal; Baard-Christian Schem; Olav Mella; Olav Dahl
PURPOSE To investigate the toxicity of combretastatin A-4 disodium phosphate (CA-4) and its vascular effects in the subcutaneous (s.c.) BT4An rat glioma, and additionally, to determine the tumor response of CA-4 combined with hyperthermia. METHODS AND MATERIALS For assessment of drug toxicity, rats were given 50, 75, or 100 mg/kg CA-4 and followed by daily registration of weight and side effects. Interstitial tumor blood flow was determined by laser Doppler flowmetry in rats injected with 50 mg/kg CA-4. In the tumor response study we administered CA-4 50 mg/kg alone or combined with hyperthermia (waterbath 44 degrees C for 60 min) 0 or 3 h later. RESULTS We found that CA-4, at a well-tolerated dose of 50 mg/kg, induced a considerable time-dependent decrease in the tumor blood flow. Tumor blood flow was reduced by 47-55% during the first 110 min after injecting CA-4, and thereafter remained decreased until the measurements were terminated. Administering CA-4 3 h before hyperthermia yielded the best tumor response and increased tumor growth time significantly compared with simultaneous administration of CA-4 and hyperthermia (p = 0.03). Interestingly, CA-4 alone did not influence tumor growth. CONCLUSION CA-4 induces a gradual reduction in tumor blood flow which can be exploited to sensitize the BT4An tumor for hyperthermia.
International Journal of Radiation Oncology Biology Physics | 1992
Baard-Christian Schem; Olav Mella; Olav Dahl
The effect of thermochemotherapy with cisplatin or carboplatin was compared in the BT4-cell line. In vitro: BT4C-cells were treated with different concentrations of cisplatin or carboplatin, with or without simultaneous hyperthermia. In vivo: Inbred BD IX rats with transplanted glioma-like BT4A or glioblastoma-like BT4An tumors on the hind leg were treated with cisplatin (4 mg/kg) or carboplatin (50 mg/kg), with or without local hyperthermia. In vitro the benefit of adding hyperthermia to chemotherapy was similar for cisplatin and carboplatin. For both cisplatin and carboplatin, the difference of treatment effect between thermochemotherapy and chemotherapy alone increased with higher drug concentrations. In vivo hyperthermia clearly enhanced the effect of carboplatin on BT4A tumors. When treating BT4An tumors, thermochemotherapy with cisplatin or carboplatin was equally effective. Both combinations were superior to treatment with hyperthermia alone. Local toxicity and weight loss following thermochemotherapy were comparable when substituting cisplatin with carboplatin.
International Journal of Hyperthermia | 1989
Baard-Christian Schem; Olav Mella; Olav Dahl
In vitro studies have shown enhanced cell killing of BCNU and hyperthermia at acutely lowered pH. In animals hypertonic glucose i.p. has repeatedly been demonstrated to reduce intratumoral pH. Effect of hyperthermia (43 degrees C for 45 min), or BCNU (3.33 micrograms/ml or both on BT4C cells were investigated in vitro, with pH 7.5, 7.0 and 6.5 in the medium during treatment. The effect of elevated glucose concentration in the medium (20 mmol/l) during treatment with hyperthermia, or BCNU, or both, was also investigated at pH 7.5. BD IX rats with transplanted BT4A or BT4An tumours on the hind foot were treated with BCNU i.p., locally applied water bath hyperthermia (44 degrees C for 45 min) or both, with or without previous glucose (6 g/kg i.p. 2 h before treatment). In vitro: low pH markedly increased cell killing by combined BCNU and hyperthermia, but pH had only a minor influence on treatment with BCNU or hyperthermia alone. Increased glucose concentration in the medium did not influence the effect of BCNU alone, hyperthermia alone, or BCNU and hyperthermia. In vivo: glucose reduced the effect of BCNU alone on BT4A tumours, but did not influence the treatment results with hyperthermia alone. However, glucose enhanced the effect of combined BCNU and hyperthermias. The effect on BT4An tumours of BCNU or hyperthermia alone were not affected by glucose, but glucose markedly enhanced the tumour effect of combined BCNU and hyperthermia. Hyperglycaemia seems to be a promising method to increase the benefit of combined hyperthermia and BCNU. However, glucose-induced altered tumour circulation could hamper the potential benefit by decreased drug uptake.
International Journal of Radiation Oncology Biology Physics | 1995
Baard-Christian Schem; Stefan Roszinski; Bård Kronen Krossnes; Olav Mella
PURPOSE Intraperitoneal hypertonic glucose has previously been shown to induce hyperglycemia, hemo-concentration, and to influence systemic and tumor circulation, and, thus, enhance the effect of thermochemotherapy with 1-(4-amino-2-methylpyrimidine-5-yl)methyl-3-(2-chloroethyl)-3-nitrosoure a (ACNU) and 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). However, the optimal timing and the precise mechanisms responsible are not known. The effect of different time intervals between glucose load and thermochemotherapy with ACNU in the treatment of BT4An tumors, therefore, was investigated. Changes of serum glucose (Se-glucose), hemoglobin, systemic circulation parameters, tumor pH, and tumor temperature, induced by intraperitoneal glucose and/or hyperthermia, were measured to assess their effect on tumor growth. METHODS AND MATERIALS (a): Inbred BD IX rats with BT4An tumors on the hind leg were treated with ACNU 7 mg/kg intravenously just before waterbath hyperthermia, and intraperitoneal hypertonic glucose (6 g/kg) at different time intervals before (240-0 min) or immediately after thermochemotherapy. (b): Intratumoral pH and temperature were measured at different intervals after intraperitoneal glucose, and during hyperthermia with or without previous glucose. (c): Hemoglobin, hematocrit, and Se-glucose were measured at different times after intraperitoneal glucose. (d): Mean arterial pressure, pulse pressure, and heart rate were measured for 120 min after intraperitoneal glucose. RESULTS (a): The number of tumor controls and the growth delay was greatest with glucose 45 min before thermochemotherapy, and least with a time interval of 240 min. Glucose after thermochemotherapy delayed tumor growth. (b): After intraperitoneal glucose alone, intratumoral pH decreased gradually from 6.76 to 5.86 after 240 min. Hyperthermia 120 min after glucose induced a rapid further pH drop, while hyperthermia alone had no significant influence on pH. Intratumoral temperature was higher during hyperthermia in animals given glucose. (c): A substantial rise of Se-glucose and hemoglobin developed. The hemoconcentration was maintained also after reduction of Se-glucose towards normal values. (d): An initial tachycardia, and a reduction of the mean arterial pressure of about 10% 5-45 min after was measured. CONCLUSION The data indicate that a complex interaction between gradually reduced tumor pH, hyperglycemia, hemoconcentration, and reduced tumor blood flow, and not a breakdown of systemic circulation, is responsible for the effect of intraperitoneal glucose on thermochemotherapy with ACNU. Interestingly, enhancement of thermochemotherapy effect was also seen when intraperitoneal glucose was given after heat and ACNU.
Journal of Molecular Medicine | 1988
G. Wiedemann; Olav Mella; R. S. Coltart; Baard-Christian Schem; Olav Dahl
SummaryWe report three patients with advanced breast cancer who received hyperthermia (43°C over 1 h, weekly ×4) and radiotherapy as palliative treatment for chest-wall recurrence. The case reports demonstrate situations where hyperthermia may be beneficial. These include tumours where radiotherapy alone is not expected to achieve control, such as large fungating tumours, and in previously irradiated areas. In these patients, hyperthermia with radiation achieves better local control of the tumour and delays the need for systemic chemotherapy. This may improve the quality of palliation.
International Journal of Hyperthermia | 2005
B. T. Hjertaker; T. Frøystein; Baard-Christian Schem
Since December 2001, the Department of Oncology and Medical Physics, Haukeland University Hospital, Norway has been conducting whole body hyperthermia (WBH) studies, treating patients with either ovarian carcinoma or non-Hodgkin lymphomas. Accurate and reliable thermometry instrumentation is important in all types of hyperthermia procedures, particularly in WBH, where the target patient body temperature is 41.8°C. Reliable documentation of side-effects in clinical studies is also dependent on precise temperature monitoring, since in this temperature range even small, but systematic, inaccuracies (0.1–0.2°C) in the temperature monitoring is expected to affect the amount of side effects. Readily available heating and temperature data from previous treatment sessions of the same patient is also valuable for precise temperature control in future treatment sessions. The WBH thermometry system implemented at Haukeland University Hospital is described. It is based on commercially available components, including standard medical thermistor probes, and includes a temperature calibration and verification facility. The thermometry system is accurate, reliable, easy to use, comfortable for the patient and relatively inexpensive. By implementing the Steinhart-Hart polynomial fit to standard medical thermistor probe data, it is shown that the WBH treatment thermometers used can measure the patient body temperatures with a short- and long-term accuracy of ± 0.01°C.
International Journal of Hyperthermia | 1996
Baard-Christian Schem; Olav Mella; Stefan Roszinski; Olav Dahl
The influence of hypertonic glucose i.p. on development of thermotolerance and thermochemosensitivity with BCNU in thermotolerant tumours, and on intratumoural pH alterations in previously unheated and thermotolerant tumours, was investigated in BT4An tumours grown on the hind foot of BD IX rats. Thermotolerance was induced with local waterbath hyperthermia (44 degrees C/45 min) 24 h before start of test treatment. Hypertonic glucose immediately after priming hyperthermia did not inhibit development of thermotolerance, despite a significant reduction of pH by glucose. The pH reduction was less in thermotolerant tumours. Glucose administered before treatment of thermotolerant tumours did not change the growth rate of tumours treated with hyperthermia (44 degrees C/45 min), BCNU (20 or 25 mg/kg i.p.) or thermochemotherapy with a low or high dose BCNU (10 or 20 mg/kg), in contrast to previous results, where glucose enhanced thermochemosensitivity of non-thermotolerant tumours.
Acta Oncologica | 1999
Olav Dahl; Dalene R; Baard-Christian Schem; Olav Mella