85 research outputs found

    Hyperthermia for the Treatment of Locally Advanced Cervix Cancer

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    (English): There is a strong biological rationale for the use of hyperthermia as an oncological treatment modality. Fifteen randomized trials have shown significant improvement in clinical outcome when hyperthermia was added to radiotherapy, chemotherapy or both. At temperatures ≥ 40 0C, heat can cause direct celldeath, especially affecting cells that are relatively resistant to chemotherapy and radiotherapy. In this thesis, the status of hyperthermia in the treatment of locally advanced cervix cancer in the Netherlands is presented and factors predicting outcome are identified. Further, one possible way of improving treatment quality, i.e. by using hyperthermia treatment planning, is explored. The addition of hyperthermia to in this clinical setting results in a significant improvement in local control and a doubling of overall survival, without adding to long-term treatment-related toxicity. Patient-related predictive factors in this clinical setting are tumor stage, tumor size and patient performance status, while the radiation dose as well as thermal dose are predictive treatment-related factors. We found a significant relationship between thermal dose and clinical outcome for 420 patients, indicating that improvement in clinical outcome can be achieved with increased thermal dose. With the help of a hyperthermia treatment planning system, a computer program that optimizes temperature distributions for specific patients, possibly treatment quality can be improved and the thermal dose can be increased. In this thesis, such a computer program is described and adjusted for routine clinical use. Lastly, we conducted a randomized trial to assess its current contribution to treatment quality and thermal dose. (Dutch): Er is een sterke biologische rationale voor het gebruik van hyperthermia in de behandeling van kanker. Vijftien gerandomiseerde onderzoeken hebben aangetoond dat de klinische uitkomst significant verbeterd als hyperthermie wordt toegevoegd aan radiotherapie, chemotherapie of beide. Bij temperaturen ≥ 40 0C, kan warmte direct celdood veroorzaken, met name bij cellen die relatief ongevoelig zijn voor de effecten van radiotherapie en chemotherapie. In dit proefschrift wordt de huidige status van hyperthermie in de behandeling van locaal uitgebreide baarmoederhalskanker onderzocht en worden prognostische factoren geïdentificeerd. Als hyperthermie wordt toegevoegd aan radiotherapie in deze setting, resulteert dit in een significante verbetering van de locale controle en verdubbelt de overleving, zonder dat de bijwerkingen van de behandeling op de lange termijn toenemen. Factoren als tumorstadium, tumorgrootte en algemene conditie van de patiënt beïnvloedden de uitkomst, maar ook de radiotherapie- en hyperthermie-dosis zijn significant. We vonden een significante relatie tussen de hyperthermie-dosis en de klinische uitkomst voor een groep van 420 patiënten, wat erop duidt dat de klinische uitkomst verbeterd bij hogere hyperthermie-doses. Met behulp van een hyperthermie planningssysteem, een computersysteem waarmee de temperatuurverdeling kan worden geoptimaliseerd, kunnen we mogelijk de kwaliteit van behandeling en ook de hyperthermie-dosis verhogen. In dit proefschrift wordt zo’n computerprogramma beschreven en aangepast voor klinisch gebruik. Ook deden we een gerandomiseerd onderzoek op de bijdrage van het computersysteem aan de kwaliteit en hyperthermie-dosis te onderzoeken

    A moderate thermal dose is sufficient for effective free and TSL based thermochemotherapy

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    Hyperthermia, i.e. heating the tumor to a temperature of 40–43 °C is considered by many a valuable treatment to sensitize tumor cells to radiotherapy and chemotherapy. In recent randomized trials the great potential of adding hyperthermia to chemotherapy was demonstrated for treatment of high risk soft tissue sarcoma: +11.4% 5 yrs. overall survival (OS) and for ovarian cancer with peritoneal involvement nearly +12 months OS gain. As a result interest in combining chemotherapy with hyperthermia, i.e. thermochemotherapy, is growing. Extensive biological research has revealed that hyperthermia causes multiple effects, from direct cell kill to improved oxygenation, whereby each effect has a specific temperature range. Thermal sensitization of the tumor cell for chemotherapy occurs for many drugs at temperatures ranging from 40 to 42 °C with little additional increase of sensitization at higher temperatures. Increasing perfusion/oxygenation and increased extravasation are two other important hyperthermia induced mechanisms. The combination of free drug and hyperthermia has not been found to increase tumor drug concentration. Hence, enhanced effectiveness of free drug will de

    Hyperthermia dose-effect relationship in 420 patients with cervical cancer treated with combined radiotherapy and hyperthermia

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    Adding hyperthermia to standard radiotherapy (RT + HT) improves treatment outcome for patients with locally advanced cervical cancer (LACC). We investigated the effect of hyperthermia dose on treatment outcome for patients with LACC treated with RT + HT. We collected treatment and outcome data of 420 patients with LACC treated with hyperthermia at our institute from 1990 to 2005. Univariate and multivariate analyses were performed on response rate, local control, disease-specific survival and toxicity for these patients to search for a thermal dose response relationship. Besides commonly identified prognostic factors in LACC like tumour stage, performance status, radiotherapy dose and tumour size, thermal parameters involving both temperature and duration of heating emerged as significant predictors of the various end-points. The more commonly used CEM43T90 (cumulative equivalent minutes of T90 above 43 degrees C) was less influential than TRISE (based on the average T50 increase and the duration of heating, normalised to the scheduled duration of treatment). CEM43T90 and TRISE measured intraluminally correlate significantly and independently with tumour control and survival. These findings stimulate further technological development and improvement of deep hyperthermia, as they strongly suggest that it might be worthwhile to increase the thermal dose for LACC, either by treatment optimisation or by prolonging the treatment time. These results also confirm the beneficial effects from hyperthermia as demonstrated in our earlier randomised trial, and justify applying radiotherapy and hyperthermia as treatment of choice for patients with advanced cervical cancer. (c) 2009 Elsevier Ltd. All rights reserved

    Standardization of patient modeling in hyperthermia simulation studies: introducing the Erasmus Virtual Patient Repository

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    Purpose: Thermal dose-effect relations have demonstrated that clinical effectiveness of hyperthermia would benefit from more controlled heating of the tumor. Hyperthermia treatment planning (HTP) is a potent tool to study strategies enabling target conformal heating, but its accuracy is affected by patient modeling approximations. Homogeneous phantoms models are being used that do not match the body shape of patients in treatment position and often have unrealistic target volumes. As a consequence, simulation accuracy is affected, and performance comparisons are difficult. The aim of this study is to provide the first step toward standardization of HTP simulation studies in terms of patient modeling by introducing the Erasmus Virtual Patient Repository (EVPR): a virtual patient model database.Methods: Four patients with a tumor in the head and neck or the pelvis region were selected, and corresponding models were created using a clinical segmentation procedure. Using the Erasmus University Medical Center standard procedure, HTP was applied to these models and compared to HTP for commonly used surrogate models.Results: Although this study was aimed at presenting the EVPR database, our study illustrates that there is a non-negligible difference in the predicted SAR patterns between patient models and homogeneous phantom-based surrogate models. We further demonstrate the dif

    Clinical performance and future potential of magnetic resonance thermometry in hyperthermia

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    Hyperthermia treatments in the clinic rely on accurate temperature measurements to guide treatments and evaluate clinical outcome. Currently, magnetic resonance thermometry (MRT) is the only clinical option to non-invasively measure 3D temperature distributions. In this review, we evaluate the status quo and emerging approaches in this evolving technology for replacing conventional dosimetry based on intraluminal or invasively placed probes. First, we define standard-ized MRT performance thresholds, aiming at facilitating transparency in this field when comparing MR temperature mapping performance for the various scenarios that hyperthermia is currently applied in the clinic. This is based upon our clinical experience of treating nearly 4000 patients with superficial and deep hyperthermia. Second, we perform a systematic literature review, assessing MRT performance in (I) clinical and (II) pre-clinical papers. From (I) we identify the current clinical status of MRT, including the problems faced and from (II) we extract promising new techniques with the potential to accelerate progress. From (I) we found that the basic requirements for MRT during hyperthermia in the clinic are largely met for regions without motion, for example extremities. In more challenging regions (abdomen and thorax), progress has been stagnating after the clinical introduction of MRT-guided hyperthermia over 20 years ago. One clear difficulty for advancement is that performance is not or not uniformly reported, but also that studies often omit important details regarding their approach. Motion was found to be the common main issue hindering accurate MRT. Based on (II), we reported and highlighted promising developments to tackle the issues resulting from motion (directly or indirectly), including new developments as well as optimization of already existing strategies. Combined, these may have the potential to facilitate improvement in MRT in the form of more stable and reliable measurements via better stability and accuracy

    A Genomic Urine Assay for Surveillance of Patients with Bladder Cancer Treated with Radiotherapy

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    Background: Patients with muscle-invasive bladder cancer (MIBC) who receive radiotherapy with curative intent are followed by imaging, cystoscopy, and urine cytology. However, interpretation of cytology and cystoscopy is hampered by the impact of ionizing radiation on cells. Objective: To assess the diagnostic performance of a genomic urine assay to detect urinary tract recurrences in patients with MIBC treated by (chemo)radiation. Design, setting, and participants: Patients with nonmetastatic MIBC who underwent (chemo)radiation with curative intent from 2016 to 2020 were prospectively included. Follow-up consisted of cystoscopy and upper tract imaging. Prior to cystoscopy, a urine sample was analyzed to assess mutations in the genes FGFR3, HRAS, and TERT and methylation of OTX1, TWIST1, and ONECUT2. The treating physician was blinded for the assay result. Outcome measurements and statistical analysis: The primary endpoint was a urinary tract recurrence. Cross-sectional sensitivity, specificity, and negative predictive value (NPV) were analyzed using a previously developed logistic regression model for the detection of bladder cancer with this assay. The secondary endpoint was the risk of a future urinary tract recurrence following a positive test and negative cystoscopy/imaging, using a time-dependent Cox proportional hazard analysis. Results and limitations: A total of 143 patients were included, and 503 urine samples were analyzed. The median study duration was 20 mo (interquartile range [IQR] 10–33), and the median time to a recurrence was 16 mo (IQR 12–26). In 27 patients, 32 urinary tract recurrences were diagnosed, including three upper tract tumors. Of 32 recurrences, 18 (56%) had a concomitant urine test available. The diagnostic model had an area under the curve of 0.80 (95% confidence interval [CI] 0.69–0.90) with corresponding sensitivity, specificity, and NPV of 78 (95% CI 52–94), 77% (95% CI 73–81), and 99% (95% CI 97–100). When taking into account the anticipatory effect of the test, 28/32 (88%) recurrences were detected. A Cox regression analysis showed a hazard ratio of 14.8 for the development of a future recurrence (p &lt; 0.001). A major limitation was the lack of a concomitant urine test result in 14/32 (44%) recurrences. Conclusions: A genomic urine assay detected urinary tract recurrences after (chemo)radiation in patients with MIBC, and a positive test was strongly associated with future recurrences. Although validation in a large cohort is warranted, the test has the potential to limit frequent cystoscopies. Patient summary: Radiotherapy is a bladder-sparing treatment in patients with bladder cancer. After treatment, these patients undergo visual inspection of the bladder by cystoscopy to detect possible recurrences. However, interpretation of cystoscopy is difficult due to the effects of radiation on the bladder lining. Hence, we analyzed the diagnostic value of a molecular urine test to detect recurrent disease in bladder cancer patients treated by radiotherapy, and we showed that the urine test has the potential to limit the number of cystoscopies.</p

    Treatment of early-stage breast cancer with percutaneous thermal ablation, an open-label randomised phase 2 screening trial:rationale and design of the THERMAC trial

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    INTRODUCTION: Breast cancer is the most frequently diagnosed malignancy worldwide but almost half of the patients have an excellent prognosis with a 5-year survival rate of 98%–99%. These patients could potentially be treated with thermal ablation to avoid surgical excision, reduce treatment-related morbidity and increase patients’ quality of life without jeopardising treatment effectiveness. Previous studies showed highest complete ablation rates for radiofrequency, microwave and cryoablation. However, due to heterogeneity among studies, it is unknown which of these three techniques should be selected for a phase 3 comparative study. METHODS AND ANALYSIS: The aim of this phase 2 screening trial is to determine the efficacy rate of radiofrequency, microwave and cryoablation with the intention to select one treatment for further testing in a phase 3 trial. Additionally, exploratory data are obtained for the phase 3 trial. The design is a multicentre open-label randomised phase 2 screening trial. Patients with unifocal, invasive breast cancer with a maximum diameter of 2 cm without lymph node or distant metastases are included. Triple negative, Bloom-Richardson grade 3 tumours and patients with an indication for neoadjuvant chemotherapy will be excluded. Included patients will be allocated to receive one of the three thermal ablation techniques. Three months later surgical excision will be performed to determine the efficacy of thermal ablation. Treatment efficacy in terms of complete ablation rate will be assessed with CK 8/18 and H&E staining. Secondary outcomes include feasibility of the techniques in an outpatient setting, accuracy of MRI for complete ablation, patient satisfaction, adverse events, side effects, cosmetic outcome, system usability and immune response. ETHICS AND DISSEMINATION: This study protocol was approved by Medical Research Ethics Committee of the Erasmus Medical Center, Rotterdam, the Netherlands. Study results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NL9205 (www.trialregister.nl); Pre-results

    Quantitative, Multi-institutional Evaluation of MR Thermometry Accuracy for Deep-Pelvic MR-Hyperthermia Systems Operating in Multi-vendor MR-systems Using a New Anthropomorphic Phantom

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    Clinical outcome of hyperthermia depends on the achieved target temperature, therefore target conformal heating is essential. Currently, invasive temperature probe measurements are the gold standard for temperature monitoring, however, they only provide limited sparse data. In contrast, magnetic resonance thermometry (MRT) provides unique capabilities to non-invasively measure the 3D-temperature. This study investigates MRT accuracy for MR-hyperthermia hybrid systems located at five European institutions while heating a centric or eccentric target in anthropomorphic phantoms with pelvic and spine structures. Scatter plots, root mean square error (RMSE) and Bland–Altman analysis were used to quantify accuracy of MRT compared to high resistance thermistor probe measurements. For all institutions, a linear relation between MRT and thermistor probes measurements was found with R2 (mean ± standard deviation) of 0.97 ± 0.03 and 0.97 ± 0.02, respectively for centric and eccentric heating targets. The RMSE was found to be 0.52 ± 0.31 °C and 0.30 ± 0.20 °C, respectively. The Bland-Altman evaluation showed a mean difference of 0.46 ± 0.20 °C and 0.13 ± 0.08 °C, respectively. This first multi-institutional evaluation of MR-hyperthermia hybrid systems indicates comparable device performance and good agreement between MRT and thermistor probes measurements. This forms the basis to standardize treatments in multi-institution studies of MR-guided hyperthermia and to elucidate thermal dose-effect relations
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