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1.
Int J Hyperthermia ; 20(5): 451-63, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15277019

RESUMEN

PURPOSE: Thermoradiotherapy has been shown in several randomized trials to increase local control compared to radiotherapy alone. The first randomized study of interstitial hyperthermia in glioblastoma multiforme showed a survival benefit for hyperthermia, though small. Improvement of the heating technique could lead to improved results. The purpose of this feasibility study is to present the clinical and thermal data of application of an improved interstitial hyperthermia system. METHODS AND MATERIALS: Six patients with a glioblastoma multiforme were treated with interstitial hyperthermia using the Multi Electrode Current Source Interstitial Hyperthermia (MECS-IHT) system. The MECS-IHT system has the capability of spatial monitoring of temperature and individually steering of heating electrodes. Three sessions were given aiming at a steady state temperature of 42 degrees C for 1 h, with an interval of 3-4 days, during an external irradiation scheme of 60 Gy in 6 weeks. Hyperthermia was delivered with a mean of 10 catheters, 18 heating electrodes and 38 thermal probes per patient. RESULTS: Sub-optimal temperatures were encountered in the first two patients leading to adjustments in technique thereafter with subsequent improvement of thermal data. With a catheter spacing of 11-12 mm, measurements yielded a mean T(90), T(50) and T(10) of 39.9, 43.7 and 45.2 degrees C, respectively, over three sessions in the last patient. The power per electrode to reach this temperature distribution varied from 25-100% of full power in each of the last four patients. Thermal data were reproducible over the three sessions. Acute toxicity was minimal. CONCLUSIONS: Despite the spatial steering capabilities of the MECS-IHT system, a large temperature heterogeneity was encountered. The heterogeneity was the reason to limit the catheter spacing to 11-12 mm, thus making only small tumour volumes feasible for interstitial heating.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/terapia , Glioblastoma/radioterapia , Glioblastoma/terapia , Hipertermia Inducida/métodos , Anciano , Neoplasias Encefálicas/patología , Terapia Combinada , Estudios de Factibilidad , Glioblastoma/patología , Humanos , Hipertermia Inducida/efectos adversos , Hipertermia Inducida/instrumentación , Masculino , Persona de Mediana Edad
2.
BJU Int ; 93(1): 36-41, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14678364

RESUMEN

OBJECTIVE: To report an interim clinical evaluation of combined external beam irradiation (EBRT) and interstitial or regional hyperthermia in the treatment of locally advanced prostate cancer. PATIENTS AND METHODS: From 1997 to 2001, 26 patients with T3-4/NX/0M0 prostate carcinoma were treated with a combination of conformal EBRT and hyperthermia. Fourteen patients received five weekly regional hyperthermia treatments within an optimization (phase II) study, using the coaxial transverse electrical magnetic system. Twelve patients received one interstitial hyperthermia treatment within a feasibility study (phase I), using the multi-electrode current source system. Irradiation was delivered using a conformal three-field technique, administering 70 Gy in 2-Gy fractions in 7 weeks. RESULTS: The mean initial prostate-specific antigen level was 26 ng/mL. Three patients had a T4 and 23 a T3 tumour; the tumours were classified as well (four), moderately (16) and poorly (six) differentiated. The mean follow-up was 36 months. In the combined treatments there was no toxicity of more than grade 2. In regional hyperthermia the mean index temperature (T90 and T50, i.e. exceeded by 90% and 50% of the measurements) was 40.2 degrees C and 40.8 degrees C, and for interstitial hyperthermia 39.4 degrees C and 41.8 degrees C, respectively. All patients survived; seven patients had a biochemical relapse (27%), three in the regional and four in the interstitial group. The actuarial probability of freedom from biochemical relapse was 70% at 36 months for all patients together, 79% for regional and 57% for interstitial. No factors were found that could be used to predict relapse. CONCLUSIONS: The clinical outcome in these patients with advanced localized prostate cancer seems to compare favourably with most series using irradiation alone, and the treatment caused no severe complications.


Asunto(s)
Hipertermia Inducida/métodos , Neoplasias de la Próstata/terapia , Anciano , Terapia Combinada/métodos , Supervivencia sin Enfermedad , Estudios de Factibilidad , Estudios de Seguimiento , Humanos , Hipertermia Inducida/efectos adversos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/radioterapia , Resultado del Tratamiento
3.
Int J Hyperthermia ; 19(5): 481-97, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12944164

RESUMEN

A study was performed on regional hyperthermia for patients with locally advanced prostate carcinoma. The primary objective was to analyse the thermometry data with an emphasis on the possibility of replacing invasive thermometry by tumour-related intra-luminal thermometry. Fourteen patients were treated with a combination of conformal external beam radiotherapy (70 Gy) and hyperthermia. Hyperthermia was delivered using the Coaxial TEM system, one treatment per week, to a total of five treatments. Thermometry was performed in bladder, urethra, rectum and esophagus. Invasive thermometry in the prostate was carried out during one or two treatments for each patient by placing transperineally a central and a peripheral catheter. Heterogeneous temperature distributions were measured in the prostate. The mean average invasive temperature range was 1.1 degrees C. Due to the temperature heterogeneity and a limited number of thermometry sensors (mean 7, range 2-13), large variability between treatments and patients existed regarding achieved temperatures and dose. The mean invasive T90 was 40.2 +/- 0.6 degrees C and T50 was 40.8 +/- 0.6 degrees C. The mean Cum min T90>40.5 degrees C per treatment was 22 (range 0-50). Importantly, intra-luminal temperatures did not reliably predict invasively measured temperatures. Invasive thermometry, therefore, remains compulsory to calculate a thermal dose for an individual patient. Changes in temperature during treatment, measured by the urethral sensors, corresponded well with changes in temperature measured by the individual invasive sensors. Similar comparison of rectal temperature changes with intra-prostatic temperature changes was not as predictive. The similarity in temperature changes between the urethral and interstial sites, suggests that urethral temperatures are sufficient for treatment optimization. The SAR profile did not correspond with the temperature profile indicating heterogeneous perfusion. Although regional hyperthermia in combination with external beam radiotherapy for locally advanced prostate carcinoma is clinically feasible, the question on the importance of invasive thermometry remains.


Asunto(s)
Hipertermia Inducida/métodos , Neoplasias de la Próstata/radioterapia , Radioterapia Conformacional , Termómetros , Anciano , Temperatura Corporal , Terapia Combinada , Esófago , Estudios de Factibilidad , Calor , Humanos , Masculino , Persona de Mediana Edad , Recto , Uretra
4.
Int J Hyperthermia ; 19(4): 402-13, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12850926

RESUMEN

INTRODUCTION: The aim of this prospective study was to describe quality of life (QoL) in patients with locally advanced prostate carcinoma treated with conventional radiotherapy and to evaluate the influence of adding regional or interstitial hyperthermia. MATERIALS AND METHODS: All patients were irradiated using a CT-planned conventional three field technique, administering 70 Gy to prostate and vesicles. In two different phase I studies, hyperthermia was added to the radiotherapy. Twelve patients were treated with one interstitial hyperthermia treatment, lasting 60 min. Fourteen patients have been treated with five regional hyperthermia treatments, lasting 75 min each. In both hyperthermia studies, the body, bladder and rectum temperatures remained below safety limits. Patients treated with radiotherapy alone (n = 58) or combined with regional (n = 8) or interstitial hyperthermia (n = 12) completed the European Organization for Research and Treatment of Cancer (EORTC) core questionnaire (C30 + 3), the EORTC prostate cancer module (PR25) and the Rand 36 health survey before treatment and 1 and 6 months after completion of treatment. Analysis of Variance (ANOVA) for repeated measurements has been performed to describe the data. RESULTS: All patient groups were comparable concerning patient characteristics. No significant interaction or difference in QoL has been noticed between the two hyperthermia patient groups and the patient group without hyperthermia. Therefore, all groups were analysed together (n = 78) to detect QoL changes in time. A deterioration of QoL has been measured from baseline to 1 month after treatment. Fatigue, pain, urinary symptoms, bowel symptoms and financial difficulties increased significantly. Social, physical and role functioning worsened significantly. No differences in QoL were measured 6 months after treatment compared to the baseline measurement, except for a decrease in sexual activity. CONCLUSIONS: After radiotherapy with or without hyperthermia only a temporary deterioration of QoL occurs, concerning social, psychological and disease related symptoms. Additional hyperthermia does not seem to decrease QoL.


Asunto(s)
Hipertermia Inducida , Neoplasias de la Próstata/fisiopatología , Neoplasias de la Próstata/terapia , Calidad de Vida , Radioterapia , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/psicología , Encuestas y Cuestionarios
5.
Int J Hyperthermia ; 19(1): 58-73, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12519712

RESUMEN

Capacitively coupled hyperthermia devices are widely in use, mainly in Asian countries. In this paper, a comprehensive treatment planning system, including a Specific Absorption Rate (SAR) and thermal model for capacitively coupled hyperthermia, is described and demonstrated using a heterogeneous patient model. In order to accurately model a hyperthermia treatment, simulation at high resolution is mandatory. Using the quasi-static approximation, the electromagnetic problem can be solved at high resolution with acceptable computational effort. The validity of the quasi-static approximation is demonstrated by comparing the Maxwell solution of a phantom problem to the quasi-static approximation. Modelling of capacitive hyperthermia of the prostate reveals the difficulty of heating deep-seated tumours in the pelvic area. Comparison of the SAR distribution in the heterogeneous patient model and a patient shaped agar phantom shows a shielding effect of the pelvic bone and the influence of the fat-muscle distribution. It is shown that evaluation of capacitive hyperthermia with agar phantoms leads to overly optimistic conclusions. Therapeutic relevant tumour temperatures can only be obtained by permitting temperature extrema in normal tissue. This concurs with clinical practice, where treatment-limiting hot spots restrict the tumour temperature. It is demonstrated that the use of very cold overlay bolus bags has only a very superficial effect. The presented model can be used for individual treatment planning and optimization, for the evaluation of capacitive applicator modifications and comparison with other devices.


Asunto(s)
Hipertermia Inducida , Modelos Biológicos , Neoplasias Pélvicas/terapia , Terapia Asistida por Computador/métodos , Campos Electromagnéticos , Etnicidad , Humanos , Fantasmas de Imagen , Somatotipos , Termografía
6.
Int J Hyperthermia ; 19(6): 655-63, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14756454

RESUMEN

In the application of regional hyperthermia, optimization of the temperature distribution remains necessary. One of the tools that might be used is a modest increase in the systemic temperature to diminish cooling by blood perfusion. This study investigates (1) if it is feasible to increase the systemic temperature by applying other cooling strategies, without inducing unacceptable systemic stress, and (2) whether a rise in systemic temperature results in improvement of tumour temperatures. Eleven patients with locally advanced cervical carcinoma and 12 patients with locally advanced prostate carcinoma were treated with our Coaxial TEM regional hyperthermia system. In this system, the temperature of the open water bolus can be easily adjusted. Two cooling methods were applied alternately, one with a relatively low water temperature (method A), the other with a higher water bolus temperature in combination with extensive head/chest cooling by a hand shower (method B). Method B resulted in significantly higher systemic temperatures, for both patient groups separately (0.8, respectively, 0.5 degrees C) and for the total patient group (0.7 degrees C). Additionally, all tumour index temperatures were higher. For the combined group (for T50: 0.4 degrees C) and for the cervix group (for T50: 0.7 degrees C), it reached statistical significance. The raise in core temperature led to a significantly higher increase in heart rate. For the group of cervix patients, higher systemic temperatures resulted in more treatment-limiting systemic stress. For the prostate patients, systemic stress was not an important issue. Since the raise in systemic temperature did not influence the overall tolerance of treatment, method B could be applied to this group. However, the increases in tumour temperatures were small, and potential hazards of systemic temperature increase should be considered.


Asunto(s)
Hipertermia Inducida/efectos adversos , Hipertermia Inducida/métodos , Neoplasias de la Próstata/terapia , Neoplasias del Cuello Uterino/terapia , Adulto , Anciano , Temperatura Corporal , Frío , Femenino , Frecuencia Cardíaca , Calor , Humanos , Masculino , Persona de Mediana Edad , Estrés Fisiológico/etiología
7.
Int J Hyperthermia ; 18(2): 104-16, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11926189

RESUMEN

Recent development of quasistatic zooming has enabled the computation of mm-resolution SAR distributions within reasonable computation times. These high-resolution SAR distributions proved to be completely dissimilar from the cm-resolution distributions. To study the impact of high-resolution SAR modelling on regional hyperthermia treatment planning (HTP), a conventional, low-resolution treatment plan is compared to an high-resolution plan. This comparison shows that the high-resolution plan yields totally different SAR and temperature distributions when compared to the conventional plan. Both SAR and temperature maxima predicted by the low-resolution plan are not predicted by the high-resolution plan and, even worse, the low-resolution plan fails to predict maxima that are predicted by the high-resolution plan. Furthermore, it appears that small-scale SAR maxima can result in temperature maxima which may cause treatment-limiting hot spots. These small-scale SAR maxima appear to be highly determined by the dielectric geometry of the patient. This demonstrates the need for an accurate, high-resolution description of this dielectric geometry. Moreover, it suggests that it may be very difficult to reduce potential treatment-limiting hot spots in clinical practice. This study demonstrates the need for high-resolution regional hyperthermia treatment planning.


Asunto(s)
Hipertermia Inducida , Terapia Asistida por Computador , Tomografía Computarizada por Rayos X
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