Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
BMC Cancer ; 17(1): 181, 2017 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-28274211

RESUMEN

BACKGROUND: A shift towards less burdening and more patient friendly treatments for breast cancer is currently ongoing. In low-risk patients with early-stage disease, accelerated partial breast irradiation (APBI) is an alternative for whole breast irradiation following breast-conserving surgery. MRI-guided single dose ablative APBI has the potential to offer a minimally burdening, non-invasive treatment that could replace current breast-conserving therapy. METHODS: The ABLATIVE study is a prospective, single arm, multicenter study evaluating preoperative, single dose, ablative radiation treatment in patients with early-stage breast cancer. Patients with core biopsy proven non-lobular invasive breast cancer, (estrogen receptor positive, Her2 negative, maximum tumor size 3.0 cm on diagnostic MRI) and a negative sentinel node biopsy are eligible. Radiotherapy (RT) planning will be performed using a contrast enhanced (CE) planning CT-scan, co-registered with a CE-MRI, both in supine RT position. A total of twenty-five consecutive patients will be treated with a single ablative RT dose of 20 Gy to the tumor and 15 Gy to the tumorbed. Follow-up MRIs are scheduled within 1 week, 2, 4 and 6 months after single-dose RT. Breast-conserving surgery is scheduled at six months following RT. Primary study endpoint is pathological complete response. Secondary study endpoints are the radiological response and toxicity. Furthermore, patients will fill out questionnaires on quality of life and functional status. Cosmetic outcome will be evaluated by the treating radiation oncologist, patient and 'Breast Cancer Conservation Treatment cosmetic results' software. Recurrence and survival rates will be assessed. The patients will be followed up to 10 years after diagnosis. If patients give additional informed consent, a biopsy and a part of the irradiated specimen will be stored at the local Biobank and used for future research on radiotherapy response associated genotyping. DISCUSSION: The ABLATIVE study evaluates MRI-guided single dose ablative RT in patients with early-stage breast cancer, aiming at a less burdening and non-invasive alternative for current breast-conserving treatment. TRIAL REGISTRATION: ClinicalTrials.gov registration number NCT02316561 . The trial was registrated prospectively on October 10th 2014.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Radioterapia de Intensidad Modulada/métodos , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Estadificación de Neoplasias , Cuidados Preoperatorios , Estudios Prospectivos , Calidad de Vida , Planificación de la Radioterapia Asistida por Computador , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
2.
Brachytherapy ; 16(2): 282-290, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28110899

RESUMEN

PURPOSE: Determining the independent effect of additional intraoperative adaptive C-arm cone-beam CT (CBCT) planning vs. transrectal ultrasound (TRUS)-guided interactive planning alone in 125I brachytherapy for prostate cancer (PCa) on biochemical disease-free survival (BDFS). METHODS AND MATERIALS: T1/T2-stage PCa patients receiving TRUS-guided brachytherapy from 2000 to 2014 were analyzed. From October 2006, patients received additional intraoperative adaptive CBCT planning for dosimetric evaluation and subsequent remedial seed placement in underdosed areas. Patients were stratified according to the National Comprehensive Cancer Network (NCCN) risk classification. Kaplan-Meier analysis was used to estimate BDFS (primary outcome), overall survival, and PCa-specific survival (secondary outcomes). Cox regression was used to assess the relation between CBCT use and biochemical failure (BF) and overall mortality. RESULTS: In all, 1623 patients were included. Median followup was 99 months (interquartile range 70-115) for TRUS patients (n = 613) and 51 months (interquartile range 29-70) for CBCT patients (n = 1010). BF occurred 203 times and 206 patients died, 26 from PCa. For TRUS and CBCT patients, 7-year BDFS was 87.2% vs. 93.5% (log rank: p = 0.04) for low, 75.9% vs. 88.5% (p < 0.001) for intermediate, and 57.1% vs. 85.0% for high-risk patients (p < 0.001). For TRUS and CBCT patients, 7-year PCa-specific survival was 96.0% vs. 100% (p < 0.0001). After Cox regression, CBCT patients had lower hazard of BF: hazard ratio (HR) 0.25 (95% confidence interval [CI]: 0.18-0.33; p < 0.0001). Corrected for confounders, CBCT remained a predictor of BF: HR 0.51 (95% CI: 0.31-0.86; p = 0.01) but not for overall mortality: HR 0.66 (95% CI: 0.40-1.07; p = 0.09). CONCLUSIONS: Additional intraoperative adaptive CBCT planning in 125I prostate brachytherapy leads to a significant increase in BDFS in all NCCN risk groups.


Asunto(s)
Braquiterapia/métodos , Radioisótopos de Yodo/administración & dosificación , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Anciano , Tomografía Computarizada de Haz Cónico/métodos , Supervivencia sin Enfermedad , Humanos , Radioisótopos de Yodo/uso terapéutico , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/mortalidad , Radiometría/métodos , Dosificación Radioterapéutica , Resultado del Tratamiento
3.
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
4.
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
5.
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
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 ; 19(6): 598-616, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14756451

RESUMEN

Local pain is a major limiting factor in regional hyperthermia treatment with radiative applicators. Absorbing structures, consisting of agar bound saline water, have been used successfully to reduce peripheral hot spots. However, both clinical experience and simulation results indicate a SAR elevation in the tissue under the edges of the absorber block. This paper investigates the effect of modification of shape, position and spatial composition of the absorber blocks on the central attenuating effect and the SAR elevating effect at the edges. A selection from a set of five options is made based on simulations with a phantom and a single ring dipole applicator. The simulations have been performed with the FDTD core of the regional hyperthermia treatment planning system. It is shown that tapering of the absorber edge and introduction of a water layer between the absorber and the skin can reduce the edge effect in the superficial fat layer by approximately 50% with respect to a rectangular absorber. A further reduction of 15% can be obtained by an absorber with an appropriate gradient of its conductivity in the direction of the dominant E-field. The modified absorbers produce a central attenuating effect comparable to the rectangular type. The use of a water layer type and a sigma gradient type absorber is also analysed in a patient anatomy, both in the dipole ring applicator, operating at 70 MHz, as well as in a three ring Cavity Slot (CS) applicator, operating at 150 MHz. The mutual influence of phase-amplitude steering and the application of absorbers is investigated in the CS applicator. It appears that absorbers have a significant influence on the interference pattern in the patient model, possibly causing substantial reduction of the SAR value in the tumour and limiting the possibility of ad hoc application of absorbers. Re-optimization can only partly cancel this effect. Local SAR reduction by phase-amplitude control alone can match or improve the effect obtained with modified absorbers.


Asunto(s)
Simulación por Computador , Hipertermia Inducida/métodos , Modelos Biológicos , Absorción , Tejido Adiposo , Huesos , Humanos , Agua
8.
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
9.
Int J Hyperthermia ; 17(3): 240-57, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11347729

RESUMEN

Local pain is the main factor that limits regional hyperthermia treatment. Using the SAR model of the regional hyperthermia treatment planning system, the capability of absorbing blocks to reduce peripheral hot spots was investigated. The effect of rectangular absorbers of various size and salinity on an elliptical phantom in the Coaxial TEM was evaluated. The computed results were compared with SAR values measured in the phantom. Absorbers of 9 x 9 x 4 cm3 and a salinity of 18 gram l(-1) provide a SAR reduction in the muscle equivalent material, centrally under the absorber of at least 50% at a depth of up to 3 cm. The effect on the central (i.e. tumour) region is less than 20%. Larger absorbers have a more global effect and cause more attenuation in the central region. The attenuating effect depends strongly on the thickness of the fat layer between muscle and absorber. More than 2 cm fat limits the effective use of absorbers. Absorbers can induce a significant increase of SAR in muscle and fat near their edges. This effect also depends on absorber size and salinity and the thickness of the fat layer. The effect of an absorber was also evaluated with a patient anatomy, yielding results in agreement with the phantom experiments.


Asunto(s)
Hipertermia Inducida , Humanos , Modelos Anatómicos
10.
Phys Med Biol ; 46(12): 3115-31, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11768495

RESUMEN

To determine the thermal dose of a hyperthermia treatment, knowledge of the three-dimensional (3D) temperature distribution is mandatory. The aim of this paper is to validate an interstitial hyperthermia treatment planning system with which the full 3D temperature distribution can be obtained in individual patients. Within a phase I study, 12 patients with prostate cancer were treated with interstitial hyperthermia using our multi electrode current source interstitial hyperthermia treatment (MECS IHT) system. The temperature distribution was measured from within the heating devices and by additional thermometry. The perfusion level was estimated and the heating implant reconstructed. The steady-state temperature distribution was calculated using our interstitial hyperthermia treatment planning system. The simulated temperature distribution was validated by individually comparing the measured and simulated thermo-sensors, both for the thermometry integrated with the heating applicators and the additional thermometry. The entire procedure was also performed on a no-flow agar-agar phantom. It was shown that the calculated temperature distribution of an individual patient during MECS interstitial hyperthermia is very heterogeneous. The validation indicates that the calculated temperature elevations match the measurements within approximately 1 degrees C. Possible improvements are more precise reconstruction, incorporation of discrete vasculature and using a temperature-dependent, heterogeneous perfusion distribution. Further technical improvements of the MECS-IHT system may also result in better temperature calculations.


Asunto(s)
Carcinoma/terapia , Hipertermia Inducida/métodos , Neoplasias de la Próstata/terapia , Agar/química , Calibración , Electrodos , Humanos , Masculino , Fantasmas de Imagen , Reproducibilidad de los Resultados , Temperatura , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA