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1.
Strahlenther Onkol ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39419904

RESUMO

BACKGROUND AND PURPOSE: Combining chemoradiotherapy (CRT) with deep regional hyperthermia (HT) shows promise for enhancing clinical outcomes in selected rectal cancer patients. This study aimed to integrate the evidence and evaluate the efficacy of this combined treatment approach. MATERIALS AND METHODS: A systematic search of the PubMed, Scopus, and Mendeley databases was performed. This review was conducted according to the PRISMA guidelines. The quality of studies was evaluated using the Newcastle-Ottawa scale (NOS). Random-effects meta-analyses (DerSimonian and Laird) were performed. The primary outcome was pathological complete response (pCR), and secondary endpoints were overall survival (OS), disease-free survival (DFS), local recurrence-free survival (LRFS), and toxicity. RESULTS: In total, 12 studies were included, mostly of moderate quality. Patients with locally advanced rectal cancer (LARC; n = 760) and locally recurrent rectal cancer (LRRC; n = 22) were eligible. The pooled pCR rate was 19% (95% confidence interval [CI]: 16-22%) among all 782 patients and 19% (95%CI:16-23%) among 760 LARC patients. Due to significant study heterogeneity, survival outcomes were pooled by excluding LRRC patients. The pooled 5­year OS rate among 433 LARC patients was 87% (95%CI: 83-90%). The pooled 5­year DFS and LRFS in LARC patients were 75% (95%CI: 70-80%) and 95% (95%CI: 92-97%), respectively. There was a lack of consistent reporting of HT treatment parameters and toxicity symptoms among the studies. CONCLUSION: The collective clinical evidence showed that neoadjuvant CRT combined with HT in rectal cancer patients is feasible, with a 19% pCR rate and excellent survival outcomes in long term follow-up.

2.
Int J Hyperthermia ; 41(1): 2379992, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39019469

RESUMO

INTRODUCTION: There is an ongoing scientific discussion, that anti-cancer effects induced by radiofrequency (RF)-hyperthermia might not be solely attributable to subsequent temperature elevations at the tumor site but also to non-temperature-induced effects. The exact molecular mechanisms behind said potential non-thermal RF effects remain largely elusive, however, limiting their therapeutical targetability. OBJECTIVE: Therefore, we aim to provide an overview of the current literature on potential non-temperature-induced molecular effects within cancer cells in response to RF-electromagnetic fields (RF-EMF). MATERIAL AND METHODS: This literature review was conducted following the PRISMA guidelines. For this purpose, a MeSH-term-defined literature search on MEDLINE (PubMed) and Scopus (Elsevier) was conducted on March 23rd, 2024. Essential criteria herein included the continuous wave RF-EMF nature (3 kHz - 300 GHz) of the source, the securing of temperature-controlled circumstances within the trials, and the preclinical nature of the trials. RESULTS: Analysis of the data processed in this review suggests that RF-EMF radiation of various frequencies seems to be able to induce significant non-temperature-induced anti-cancer effects. These effects span from mitotic arrest and growth inhibition to cancer cell death in the form of autophagy and apoptosis and appear to be mostly exclusive to cancer cells. Several cellular mechanisms were identified through which RF-EMF radiation potentially imposes its anti-cancer effects. Among those, by reviewing the included publications, we identified RF-EMF-induced ion channel activation, altered gene expression, altered membrane potentials, membrane oscillations, and blebbing, as well as changes in cytoskeletal structure and cell morphology. CONCLUSION: The existent literature points toward a yet untapped therapeutic potential of RF-EMF treatment, which might aid in damaging cancer cells through bio-electrical and electro-mechanical molecular mechanisms while minimizing adverse effects on healthy tissue cells. Further research is imperative to definitively confirm non-thermal EMF effects as well as to determine optimal cancer-type-specific RF-EMF frequencies, field intensities, and exposure intervals.


Assuntos
Campos Eletromagnéticos , Neoplasias , Humanos , Neoplasias/radioterapia , Ondas de Rádio , Animais
3.
Int J Hyperthermia ; 41(1): 2416999, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39428108

RESUMO

INTRODUCTION: Several positive clinical trials have demonstrated that capacitive hyperthermia (CHT) improves the effectiveness of radiation therapy for the treatment of various cancer entities. However, the ability of CHT to induce significant heating throughout the body is under debate. OBJECTIVES: To perform a pilot study involving comparisons of computer simulations and experimental data using different split-phantoms to validate hyperthermia treatment modeling for pre-planning for a clinical CHT system and to investigate the feasibility of split-phantom measurements in capacitive hyperthermia. MATERIALS AND METHODS: The CHT system EHY-2030 (Oncotherm, Budapest, Hungary) was used. The system provides two electrode sizes, but only the smaller electrode, indicated as D200 electrode, was investigated in this pilot study. Horizontally and vertically splittable, different multi-slice phantoms with dielectric material properties simulating muscle and electrically low conductive fat were produced and heated. During the heating procedure, temperature-time curves were measured, and thermal images were captured. Specific absorption rate values were derived from the temperature rise (TR) values. Concomitantly, computer field simulations utilizing a detailed CAD-based model of the CHT system were performed using the simulation platform Sim4Life and compared with measurements. RESULTS: For the investigated electrode D200 the system power of 75 W was applied, which is half of the maximum power of 150 W and lies in the range of usual values for this electrode applied in patient treatments in our clinic. For 75 W, a heating of 3.6 °C in 6 min in a depth of 1 cm in an agar-based, muscle tissue-equivalent phantom was achieved. The addition of a 1 cm thick, synthetic, low dielectric fat layer reduced the TR up until a depth of 8.5 cm by on average around 38% (from 8.5 cm onwards the absolute local TR is similar, deviations are ≤0.1 °C). In terms of point-to-point absolute SAR comparison (without any normalization), up to a depth of 11 cm in the phantoms central vertical plot, the simulation differs from the measured TR points by on average 25% (ranging from 7% to 36%) for the homogeneous phantom and by on average 43% (ranging from 26% to 60%) for the inhomogeneous phantom. CONCLUSION: Computer simulations and experimental data were compared for the CHT system EHY-2030 using the D200 electrode, applying a thermal imaging technique for different vertically splittable phantoms. This pilot study data can be used as a guidance regarding the expected heating for this commonly used electrode size but also to further elucidate the significance of non-thermal anticancer effects. Further studies are needed for different sizes and geometries of electrodes and phantoms.


Assuntos
Simulação por Computador , Hipertermia Induzida , Imagens de Fantasmas , Hipertermia Induzida/métodos , Hipertermia Induzida/instrumentação , Humanos , Projetos Piloto , Eletrodos
4.
Int J Hyperthermia ; 41(1): 2342348, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38653548

RESUMO

PURPOSE: To analyze the current practice of regional hyperthermia (RHT) for soft tissue sarcoma (STS) at 12 European centers to provide an overview, find consensuses and identify controversies necessary for future guidelines and clinical trials. METHODS: In this cross-sectional survey study, a 27-item questionnaire assessing clinical subjects and procedural details on RHT for STS was distributed to 12 European cancer centers for RHT. RESULTS: We have identified seven controversies and five consensus points. Of 12 centers, 6 offer both, RHT with chemotherapy (CTX) or with radiotherapy (RT). Two centers only offer RHT with CTX and four centers only offer RHT with RT. All 12 centers apply RHT for localized, high-risk STS of the extremities, trunk wall and retroperitoneum. However, eight centers also use RHT in metastatic STS, five in palliative STS, eight for superficial STS and six for low-grade STS. Pretherapeutic imaging for RHT treatment planning is used by 10 centers, 9 centers set 40-43 °C as the intratumoral target temperature, and all centers use skin detectors or probes in body orifices for thermometry. DISCUSSION: There is disagreement regarding the integration of RHT in contemporary interdisciplinary care of STS patients. Many clinical controversies exist that require a standardized consensus guideline and innovative study ideas. At the same time, our data has shown that existing guidelines and decades of experience with the technique of RHT have mostly standardized procedural aspects. CONCLUSIONS: The provided results may serve as a basis for future guidelines and inform future clinical trials for RHT in STS patients.


Assuntos
Hipertermia Induzida , Sarcoma , Humanos , Sarcoma/terapia , Hipertermia Induzida/métodos , Europa (Continente) , Inquéritos e Questionários , Estudos Transversais , Consenso
5.
Strahlenther Onkol ; 199(5): 436-444, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36038671

RESUMO

PURPOSE: The combination of hyperthermia (HT) with radio(chemo)therapy or chemotherapy (CT) is an established treatment strategy for specific indications. Its application in routine clinical practice in Europe depends on regulatory and local conditions. We conducted a survey among European clinical centers to determine current practice of HT. METHODS: A questionnaire with 22 questions was sent to 24 European HT centers. The questions were divided into two main categories. The first category assessed how many patients are treated with HT in combination with radio(chemo)therapy or CT for specific indications per year. The second category addressed which hyperthermia parameters are recorded. Analysis was performed using descriptive methods. RESULTS: The response rate was 71% (17/24) and 16 centers were included in this evaluation. Annually, these 16 centers treat approximately 637 patients using HT in combination with radio(chemo)therapy or CT. On average, 34% (range: 3-100%) of patients are treated in clinical study protocols. Temperature readings and the time interval between HT and radio(chemo)therapy or CT are recorded in 13 (81%) and 9 (56%) centers, respectively. The thermal dose quality parameter "cumulative equivalent minutes at 43 °C" (CEM43°C) is only evaluated in five (31%) centers for each HT session. With regard to treatment sequence, 8 (50%) centers administer HT before radio(chemo)therapy and the other 8 in the reverse order. CONCLUSION: There is a significant heterogeneity among European HT centers as to the indications treated and the recording of thermometric parameters. More evidence from clinical studies is necessary to achieve standardization of HT practice.


Assuntos
Hipertermia Induzida , Humanos , Hipertermia Induzida/métodos , Terapia Combinada , Europa (Continente)
6.
Int J Hyperthermia ; 40(1): 2236337, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37468132

RESUMO

BACKGROUND: The therapy of high-risk soft tissue sarcomas (STS) remains an interdisciplinary challenge. Regional hyperthermia (RHT) sparked interest as it has been shown to improve overall survival when added to perioperative chemotherapy (CTX). However, questions arise on how RHT should be optimally integrated into current multi-modal therapies. MATERIALS AND METHODS: We performed a systematic literature review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies written in English and focused mainly on radiative RHT and superficial hyperthermia were evaluated and included. Studies including patients below the age of 18, with metastatic disease or review articles, were excluded. RESULTS: We identified 15 clinical reports from 1990 until July 2022. Three articles combined RHT + CTX, and twelve focused on combined RHT + radiotherapy (RT) or neoadjuvant chemoradiotherapy (CRT). Most treatments were based on invasive thermometry, and less on magnetic resonance imaging (MRI)-based, noninvasive thermometry for STS of the extremities. Perioperative chemotherapy was used for the combination of RHT and CTX, mostly Ifosfamide-based. The effectiveness of RT appeared to be increased by RHT, especially with two RHT sessions/week. The trimodal simultaneous approach of neoadjuvant RHT and CRT was also feasible. No significant toxicity of RHT was reported. CONCLUSIONS: The gathered data strengthen the beneficial role of RHT in the multimodal setting. Further expert consensus and clinical trials are required to determine the optimal integration of RHT in treating STS.


Assuntos
Hipertermia Induzida , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Terapia Combinada , Hipertermia Induzida/métodos , Ifosfamida/uso terapêutico , Sarcoma/terapia , Neoplasias de Tecidos Moles/tratamento farmacológico
7.
Strahlenther Onkol ; 198(8): 683-689, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35704054

RESUMO

PURPOSE: The DEGRO Expert Commission on Prostate Cancer has revised the indication for radiation therapy of the primary prostate tumor in patients with synchronous distant metastases with low metastatic burden. METHODS: The current literature in the PubMed database was reviewed regarding randomized evidence on radiotherapy of the primary prostate tumor with synchronous low metastatic burden. RESULTS: In total, two randomized trials were identified. The larger study, the STAMPEDE trial, demonstrated an absolute survival benefit of 8% after 3 years for patients with low metastatic burden treated with standard of care (SOC) and additional radiotherapy (RT) (EQD2 ≤ 72 Gy) of the primary tumor. Differences in the smaller Horrad trial were not statistically significant, although risk reduction in the subgroup (< 5 bone metastases) was equal to STAMPEDE. The STOPCAP meta-analysis of both trials demonstrated the benefit of local radiotherapy for up to 4 bone lesions and an additional subanalysis of STAMPEDE also substantiated this finding in cases with M1a-only metastases. CONCLUSION: Therefore, due to the survival benefit after 3 years, current practice is changing. New palliative SOC is radiotherapy of the primary tumor in synchronously metastasized prostate cancer with low metastatic burden (defined as ≤ 4 bone metastases, with or without distant nodes) or in case of distant nodes only detected by conventional imaging.


Assuntos
Neoplasias Ósseas , Neoplasias da Próstata , Neoplasias Ósseas/secundário , Hormônios , Humanos , Masculino , Neoplasias da Próstata/patologia
8.
Int J Hyperthermia ; 39(1): 504-516, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35296213

RESUMO

OBJECTIVE: Hyperthermia as an enhancer of radio- and/or chemotherapy has been confirmed by various trials. Quite a few positive randomized trials have been carried out with capacitive hyperthermia systems (CHS), even though specific absorption rates (SAR) in deep regions are known to be inferior to the established annular-phased array techniques. Due to a lack of systematic SAR measurements for current capacitive technology, we performed phantom measurements in combination with simulation studies. MATERIALS AND METHODS: According to the current guidelines, homogeneous and inhomogeneous agarose phantoms were manufactured for the commercial CHS Celsius42. Temperature/time curves were registered, and specific absorption rate (SAR) profiles and distributions were derived using the temperature gradient method. We implemented models for electrodes and phantom setups for simulation studies using Sim4Life. RESULTS: For a standard total power of 200 W, we measured effective SAR until depths of 6-8 cm in a homogeneous phantom, which indicates fair heating conditions for tumor diseases in superficial and intermediate depths. A fat layer of 1 cm strongly weakens the SAR, but 10-20 W/kg are still achieved in intermediate to deep regions (2-10 cm). In the phantom setup with integrated bone, we measured low SAR of 5-10 W/kg in the cancellous bone. Our simulations could fairly describe the measured SAR distributions, but predict tendentially higher SAR than measured. Additional simulations suggest that we would achieve higher SAR with vital fatty tissue and bone metastases in clinical situations. CONCLUSION: Capacitive systems are suitable to heat superficial and medium-deep tumors as well as some bone metastases, and CHS application is feasible for a specific class of patients with pelvic and abdominal tumors. These findings are consistent with positive clinical studies.


Assuntos
Hipertermia Induzida , Neoplasias , Simulação por Computador , Humanos , Hipertermia , Hipertermia Induzida/métodos , Neoplasias/terapia , Imagens de Fantasmas
9.
Int J Hyperthermia ; 39(1): 1078-1087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35993234

RESUMO

BACKGROUND: Transurethral resection of bladder tumor (TUR-BT) followed by chemoradiation (CRT) is a valid treatment option for patients with muscle-invasive bladder cancer (MIBC). This study aimed to investigate the efficacy of a tetramodal approach with additional regional hyperthermia (RHT). METHODS: Patients with stages T2-4 MIBC were recruited at two institutions. Treatment consisted of TUR-BT followed by radiotherapy at doses of 57-58.2 Gy with concurrent weekly platinum-based chemotherapy and weekly deep RHT (41-43 °C, 60 min) within two hours of radiotherapy. The primary endpoint was a complete response six weeks after the end of treatment. Further endpoints were cystectomy-free rate, progression-free survival (PFS), local recurrence-free survival (LRFS), overall survival (OS) and toxicity. Quality of life (QoL) was assessed at follow-up using the EORTC-QLQ-C30 and QLQ-BM30 questionnaires. Due to slow accrual, an interim analysis was performed after the first stage of the two-stage design. RESULTS: Altogether 27 patients were included in the first stage, of these 21 patients with a median age of 73 years were assessable. The complete response rate of evaluable patients six weeks after therapy was 93%. The 2-year cystectomy-free rate, PFS, LRFS and OS rates were 95%, 76%, 81% and 86%, respectively. Tetramodal treatment was well tolerated with acute and late G3-4 toxicities of 10% and 13%, respectively, and a tendency to improve symptom-related quality of life (QoL) one year after therapy. CONCLUSION: Tetramodal therapy of T2-T4 MIBC is promising with excellent local response, moderate toxicity and good QoL. This study deserves continuation into the second stage.


Assuntos
Hipertermia Induzida , Neoplasias da Bexiga Urinária , Idoso , Terapia Combinada , Humanos , Músculos , Qualidade de Vida , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias da Bexiga Urinária/cirurgia
10.
Strahlenther Onkol ; 197(7): 575-580, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33914101

RESUMO

OBJECTIVE: The current article encompasses a literature review and recommendations for radiotherapy in nodal oligorecurrent prostate cancer. MATERIALS AND METHODS: A literature review focused on studies comparing metastasis-directed stereotactic ablative radiotherapy (SABR) vs. external elective nodal radiotherapy (ENRT) and studies analyzing recurrence patterns after local nodal treatment was performed. The DEGRO Prostate Cancer Expert Panel discussed the results and developed treatment recommendations. RESULTS: Metastasis-directed radiotherapy results in high local control (often > 90% within a follow-up of 1-2 years) and can be used to improve progression-free survival or defer androgen deprivation therapy (ADT) according to prospective randomized phase II data. Distant progression after involved-node SABR only occurs within a few months in the majority of patients. ENRT improves metastases-free survival rates with increased toxicity in comparison to SABR according to retrospective comparative studies. The majority of nodal recurrences after initial local treatment of pelvic nodal metastasis are detected within the true pelvis and common iliac vessels. CONCLUSION: ENRT with or without a boost should be preferred to SABR in pelvic nodal recurrences. In oligometastatic prostate cancer with distant (extrapelvic) nodal recurrences, SABR alone can be performed in selected cases. Application of additional systemic treatments should be based on current guidelines, with ADT as first-line treatment for hormone-sensitive prostate cancer. Only in carefully selected patients can radiotherapy be initially used without additional ADT outside of the current standard recommendations. Results of (randomized) prospective studies are needed for definitive recommendations.


Assuntos
Recidiva Local de Neoplasia/radioterapia , Neoplasias da Próstata/radioterapia , Humanos , Linfonodos/patologia , Linfonodos/efeitos da radiação , Metástase Linfática/patologia , Metástase Linfática/radioterapia , Masculino , Recidiva Local de Neoplasia/patologia , Neoplasias da Próstata/patologia , Radiocirurgia
11.
Strahlenther Onkol ; 197(11): 993-1000, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34463814

RESUMO

PURPOSE: Various randomized phase III clinical trials have compared moderately hypofractionated to normofractionated radiotherapy (RT). These modalities showed similar effectiveness without major differences in toxicity. This project was conducted by the Prostate Cancer Expert Panel of the German Society of Radiation Oncology (DEGRO) and the Working Party on Radiation Oncology of the German Cancer Society. We aimed to investigate expert opinions on the use of moderately hypofractionated RT as a definitive treatment for localized prostate cancer in German-speaking countries. METHODS: A 25-item, web-based questionnaire on moderate-hypofractionation RT was prepared by an internal committee. The experts of the DEGRO were asked to complete the questionnaire. RESULTS: Fourteen active members of DEGRO completed the questionnaire. The questions described indications for selecting patients eligible to receive moderate hypofractionation based on clinical and pathological factors such as age, urinary symptoms, and risk-group. The questions also collected information on the technical aspects of selection criteria, including the definition of a clinical target volume, the use of imaging, protocols for bladder and rectal filling, the choice of a fractionation schedule, and the use of image guidance. Moreover, the questionnaire collected information on post-treatment surveillance after applying moderately hypofractionated RT. CONCLUSION: Although opinions varied on the use of moderate-hypofractionation RT, the current survey reflected broad agreement on the notion that moderately hypofractionated RT could be considered a standard treatment for localized prostate cancer in German-speaking countries.


Assuntos
Neoplasias da Próstata , Radioterapia (Especialidade) , Fracionamento da Dose de Radiação , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Hipofracionamento da Dose de Radiação , Inquéritos e Questionários
12.
Strahlenther Onkol ; 197(2): 89-96, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33301049

RESUMO

Due to its low fractionation sensitivity, also known as "alpha/beta ratio," in relation to its surrounding organs at risk, prostate cancer is predestined for hypofractionated radiation schedules assuming an increased therapeutic ratio compared to normofractionated regimens. While moderate hypofractionation (2.2-4 Gy) has been proven to be non-inferior to normal fractionation in several large randomized trials for localized prostate cancer, level I evidence for ultrahypofractionation (>4 Gy) was lacking until recently. An accumulating body of non-randomized evidence has recently been strengthened by the publication of two randomized studies comparing ultrahypofractionation with a normofractionated schedule, i.e., the Scandinavian HYPO-RT trial by Widmark et al. and the first toxicity results of the PACE­B trial. In this review, we aim to give a brief overview of the current evidence of ultrahypofractionation, make an overall assessment of the level of evidence, and provide recommendations and requirements that should be followed before introducing ultrahypofractionation into routine clinical use.


Assuntos
Neoplasias da Próstata/radioterapia , Hipofracionamento da Dose de Radiação , Ensaios Clínicos como Assunto , Humanos , Masculino , Próstata/efeitos da radiação , Resultado do Tratamento
13.
Int J Hyperthermia ; 38(1): 715-731, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33910472

RESUMO

The temperature-independent effects of electromagnetic fields (EMF) have been controversial for decades. Here, we critically analyze the available literature on non-thermal effects of radiofrequency (RF) and microwave EMF. We present a literature review of preclinical and clinical data on non-thermal antiproliferative effects of various EMF applications, including conventional RF hyperthermia (HT, cRF-HT). Further, we suggest and evaluate plausible biophysical and electrophysiological models to decipher non-thermal antiproliferative membrane effects. Available preclinical and clinical data provide sufficient evidence for the existence of non-thermal antiproliferative effects of exposure to cRF-HT, and in particular, amplitude modulated (AM)-RF-HT. In our model, transmembrane ion channels function like RF rectifiers and low-pass filters. cRF-HT induces ion fluxes and AM-RF-HT additionally promotes membrane vibrations at specific resonance frequencies, which explains the non-thermal antiproliferative membrane effects via ion disequilibrium (especially of Ca2+) and/or resonances causing membrane depolarization, the opening of certain (especially Ca2+) channels, or even hole formation. AM-RF-HT may be tumor-specific owing to cancer-specific ion channels and because, with increasing malignancy, membrane elasticity parameters may differ from that in normal tissues. Published literature suggests that non-thermal antiproliferative effects of cRF-HT are likely to exist and could present a high potential to improve future treatments in oncology.


Assuntos
Campos Eletromagnéticos , Ondas de Rádio , Febre , Humanos , Micro-Ondas , Temperatura
14.
Int J Hyperthermia ; 38(1): 663-678, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33899658

RESUMO

OBJECTIVE: To create an improved planning method for pediatric regional hyperthermia (RHT) using the SIGMA-30 applicator (SIGMA-30). MATERIALS AND METHODS: An electromagnetic model of SIGMA-30 was generated for use with the finite-difference time-domain (FDTD) method. Applying special MATLAB-based algorithms, voxel models of a pediatric patient with pelvic rhabdomyosarcoma were created from Computed-Tomography (CT) contours for use with the FDTD method and the finite-difference (FD) method capable of using either temperature-independent or temperature-dependent perfusion models for solving the Bioheat Transfer Equation (BHTE). Patient models were parametrized regarding, first, the positioning in the applicator, second, the absorbed power range and, third, different perfusion models, resulting in the so-called Parametrized Treatment Models (PTMs). A novel dedicated optimization procedure was developed based on quantitative comparison of numerical calculations against temperature and power measurements from two RHT therapies. RESULTS: Using measured data, a realistic absorbed power range in the patient model was estimated. Within this range, several FDTD and BHTE runs were performed and, applying the aforementioned optimization scheme, the best PTMs and perfusion models were identified for each therapy via a retrospective comparison with measurements in 14 temperature sensor positions: 5 in the tumor, 8 in rectum and one in bladder. CONCLUSION: A novel dedicated optimization procedure for identification of suitable patient-specific electromagnetic and thermal models, which can be used for improved patient planning, was developed and evaluated by comparison with treatment-derived measurements using SIGMA-30. The optimization procedure can be extended to other hyperthermia applicators and to other patient types, including adults.


Assuntos
Hipertermia Induzida , Neoplasias , Algoritmos , Criança , Humanos , Hipertermia , Neoplasias/terapia , Estudos Retrospectivos
15.
Acta Radiol ; 62(9): 1200-1207, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32938221

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is the commonest malignant primary brain tumor and still has one of the worst prognoses among cancers in general. There is a need for non-invasive methods to predict individual prognosis in patients with GBM. PURPOSE: To evaluate quantitative volumetric tissue assessment of enhancing tumor volume on cranial magnetic resonance imaging (MRI) as an imaging biomarker for predicting overall survival (OS) in patients with GBM. MATERIAL AND METHODS: MRI scans of 49 patients with histopathologically confirmed GBM were analyzed retrospectively. Baseline contrast-enhanced (CE) MRI sequences were transferred to a segmentation-based three-dimensional quantification tool, and the enhancing tumor component was analyzed. Based on a cut-off percentage of the enhancing tumor volume (PoETV) of >84.78%, samples were dichotomized, and the OS and intracranial progression-free survival (PFS) were evaluated. Univariable and multivariable analyses, including variables such as sex, Karnofsky Performance Status score, O6-methylguanine-DNA-methyltransferase status, age, and resection status, were performed using the Cox regression model. RESULTS: The median OS and PFS were 16.9 and 7 months in the entire cohort, respectively. Patients with a CE tumor volume of >84.78% showed a significantly shortened OS (12.9 months) compared to those with a CE tumor volume of ≤84.78% (17.7 months) (hazard ratio [HR] 2.72; 95% confidence interval [CI] 1.22-6.03; P = 0.01). Multivariable analysis confirmed that PoETV had a significant prognostic role (HR 2.47; 95% CI 1.08-5.65; P = 0.03). CONCLUSION: We observed a correlation between PoETV and OS. This imaging biomarker may help predict the OS of patients with GBM.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Imageamento por Ressonância Magnética/métodos , Carga Tumoral , Adulto , Idoso , Biomarcadores Tumorais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neoplasias Encefálicas/mortalidade , Estudos de Coortes , Meios de Contraste , Estudos de Avaliação como Assunto , Feminino , Glioblastoma/mortalidade , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
16.
Int J Cancer ; 147(5): 1427-1436, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32010957

RESUMO

We have investigated the prognostic value of two novel interim 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) parameters in patients undergoing chemoradiation (CRT) for esophageal squamous cell carcinoma (ESCC): one tumor parameter (maximal standardized uptake ratio rSUR) and one normal tissue parameter (change of FDG uptake within irradiated nontumor-affected esophagus ∆SUVNTO ). PET data of 134 European and Chinese patients were analyzed. Parameter establishment was based on 36 patients undergoing preoperative CRT plus surgery, validation was performed in 98 patients receiving definitive CRT. Patients received PET imaging prior and during fourth week of CRT. Clinical parameters, baseline PET parameters, and interim PET parameters (rSUR and ∆SUVNTO ) were analyzed and compared to event-free survival (EFS), overall survival (OS), loco-regional control (LRC) and freedom from distant metastases (FFDM). Combining rSUR and ∆SUVNTO revealed a strong prognostic impact on EFS, OS, LRC and FFDM in patients undergoing preoperative CRT. In the definitive CRT cohort, univariate analysis with respect to EFS revealed several staging plus both previously established interim PET parameters as significant prognostic factors. Multivariate analyses revealed only rSUR and ∆SUVNTO as independent prognostic factors (p = 0.003, p = 0.008). Combination of these parameters with the cutoff established in preoperative CRT revealed excellent discrimination of patients with a long or short EFS (73% vs. 17% at 2 years, respectively) and significantly discriminated all other endpoints (OS, p < 0.001; LRC, p < 0.001; FFDM, p = 0.02), even in subgroups. Combined use of interim FDG-PET derived parameters ∆SUVNTO and rSUR seems to have predictive potential, allowing to select responders for definitive CRT and omission of surgery.


Assuntos
Neoplasias Esofágicas/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Fluordesoxiglucose F18/uso terapêutico , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/uso terapêutico , Idoso , Quimiorradioterapia , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/terapia , Feminino , Fluordesoxiglucose F18/metabolismo , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Compostos Radiofarmacêuticos/metabolismo , Estudos Retrospectivos , Taxa de Sobrevida
17.
Strahlenther Onkol ; 196(3): 229-242, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31873779

RESUMO

PURPOSE: To evaluate treatment outcomes for patients with localized prostate cancer who were treated with dose-escalated primary image-guided radiation therapy (IGRT). METHODS: We retrospectively analyzed 88 consecutive patients treated using helical tomotherapy with daily megavoltage CTs (MVCT). Patients were prescribed daily doses of 1.8 Gy to the planning target volume (PTV) and 2 Gy to the clinical target volume (CTV). Low- and favorable intermediate-risk patients received a minimum total dose of 72 Gy to the PTV and up to 80 Gy to the CTV. Unfavorable intermediate-risk and high-risk patients received a minimum total dose of 75.6 Gy to the PTV and up to 84 Gy to the CTV. We assessed freedom from biochemical relapse (FFBF), 5­year biochemical recurrence-free survival (5-bRFS), distant metastasis-free survival (5-dMFS), and cancer-specific survival (5-CSS) as well as acute and late genitourinary (GU) and gastrointestinal (GI) toxicity. RESULTS: Among our cohort, 11.4% were low-risk, 50% intermediate-risk, and 38.6% high-risk patients according to the D'Amico criteria. Median follow-up was 66 months (range 8-83 months). FFBF was 100%, 97.7%, and 90.7%; 5­bRFS was 100%, 92.8%, and 70.4%; 5­dMFS was 100%, 92.7%, and 70.4%; and 5­CSS was 100%, 97.4%, and 89.8% for low-, intermediate-, and high-risk patients, respectively. Grades 2 and 3 toxicity occurred at the following rates: acute GU toxicity 39.8% and 1.1%, acute GI toxicity 12.5% and 0%, late GU toxicity 19.3% and 4.5%, and late GI toxicity 4.5% and 1.1% of patients, respectively. No toxicity >grade 3 was observed. CONCLUSION: Risk-adapted dose-escalated IGRT with helical tomotherapy of up to 84 Gy is a feasible and well-tolerable treatment scheme with promising oncological results.


Assuntos
Neoplasias da Próstata/radioterapia , Radioterapia Guiada por Imagem/métodos , Idoso , Idoso de 80 Anos ou mais , Gastroenteropatias/etiologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Próstata/patologia , Próstata/efeitos da radiação , Neoplasias da Próstata/patologia , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Resultado do Tratamento , Doenças Urológicas/etiologia
18.
Strahlenther Onkol ; 196(7): 589-597, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32166452

RESUMO

AIM: To provide an overview on the available treatments to prevent and reduce gynecomastia and/or breast pain caused by antiandrogen therapy for prostate cancer. METHODS: The German Society of Radiation Oncology (DEGRO) expert panel summarized available evidence published and assessed the validity of the information on efficacy and treatment-related toxicity. RESULTS: Eight randomized controlled trials and one meta-analysis were identified. Two randomized trials demonstrated that prophylactic radiation therapy (RT) using 1â€¯× 10 Gy or 2â€¯× 6 Gy significantly reduced the rate of gynecomastia but not breast pain, as compared to observation. A randomized dose-finding trial identified the daily dose of 20 mg tamoxifen (TMX) as the most effective prophylactic dose and another randomized trial described that daily TMX use was superior to weekly use. Another randomized trial showed that prophylactic daily TMX is more effective than TMX given at the onset of gynecomastia. Two other randomized trials described that TMX was clearly superior to anastrozole in reducing the risk for gynecomastia and/or breast pain. One comparative randomized trial between prophylactic RT using 1â€¯× 12 Gy and TMX concluded that prophylactic TMX is more effective compared to prophylactic RT and furthermore that TMX appears to be more effective to treat gynecomastia and/or breast pain when symptoms are already present. A meta-analysis confirmed that both prophylactic RT and TMX can reduce the risk of gynecomastia and/or breast pain with TMX being more effective; however, the rate of side effects after TMX including dizziness and hot flushes might be higher than after RT and must be taken into account. Less is known regarding the comparative effectiveness of different radiation fractionation schedules and more modern RT techniques. CONCLUSIONS: Prophylactic RT as well as daily TMX can significantly reduce the incidence of gynecomastia and/or breast pain. TMX appears to be an effective alternative to RT also as a therapeutic treatment in the presence of gynecomastia but its side effects and off-label use must be considered.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antagonistas de Androgênios/efeitos adversos , Androgênios , Antineoplásicos Hormonais/efeitos adversos , Moduladores de Receptor Estrogênico/uso terapêutico , Ginecomastia/induzido quimicamente , Mastodinia/induzido quimicamente , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Tamoxifeno/uso terapêutico , Anastrozol/uso terapêutico , Antagonistas de Androgênios/uso terapêutico , Anilidas/efeitos adversos , Antineoplásicos Hormonais/uso terapêutico , Tontura/induzido quimicamente , Fracionamento da Dose de Radiação , Esquema de Medicação , Moduladores de Receptor Estrogênico/administração & dosagem , Moduladores de Receptor Estrogênico/efeitos adversos , Rubor/induzido quimicamente , Ginecomastia/tratamento farmacológico , Ginecomastia/prevenção & controle , Ginecomastia/radioterapia , Humanos , Masculino , Mastodinia/tratamento farmacológico , Mastodinia/prevenção & controle , Mastodinia/radioterapia , Metanálise como Assunto , Nitrilas/efeitos adversos , Uso Off-Label , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamoxifeno/administração & dosagem , Tamoxifeno/efeitos adversos , Compostos de Tosil/efeitos adversos
19.
Strahlenther Onkol ; 196(2): 109-116, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31784804

RESUMO

OBJECTIVE: This article aims to provide an overview of the role of combined radiation and androgen deprivation (ADT) therapy in patients with intermediate-risk prostate cancer. MATERIALS AND METHODS: The current German, European, and NCCN (National Comprehensive Cancer Network) guidelines as well as relevant literature in the PubMed database which provide information on sub-classification within the intermediate-risk group and the use of ADT in terms of oncological outcome were reviewed. RESULTS: Different recommendations for risk-group assessment of patients with localized prostate cancer are available. Subdivision of intermediate risk into a favorable and an unfavorable group seems to be justified to allow for a more individualized therapy in a quite heterogenous group of patients. So far, multiple randomized trials have shown a benefit when radiation therapy (RT) is combined with ADT. The use of dose-escalated RT without ADT also appears to be an adequate therapy associated with a very low rate of cancer-specific deaths. Therefore, taking into account the increased rate of toxicity associated with ADT, dose-escalated RT alone might be justified, especially in favorable intermediate-risk patients. CONCLUSION: Dose-escalated RT alone appears to be an appropriate treatment in favorable intermediate-risk patients. Addition of short course ADT (4-6 months) might improve outcomes in unfavorable intermediate-risk patients.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Quimiorradioterapia , Neoplasias da Próstata/terapia , Humanos , Masculino , Medicina de Precisão , Dosagem Radioterapêutica , Medição de Risco
20.
Int J Hyperthermia ; 37(1): 549-563, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32484019

RESUMO

Purpose: Thermal intervention is a potent sensitizer of cells to chemo- and radiotherapy in cancer treatment. Glioblastoma multiforme (GBM) is a potential clinical target, given the cancer's aggressive nature and resistance to current treatment options. The annular phased array (APA) technique employing electromagnetic waves in the radiofrequency (RF) range allows for localized temperature increase in deep seated target volumes (TVs). Reports on clinical applications of the APA technique in the brain are still missing. Ultrahigh field magnetic resonance (MR) employs higher frequencies than conventional MR and has potential to provide focal temperature manipulation, high resolution imaging and noninvasive temperature monitoring using an integrated RF applicator (ThermalMR). This work examines the applicability of RF applicator concepts for ThermalMR of brain tumors at 297 MHz (7.0 Tesla).Methods: Electromagnetic field (EMF) simulations are performed for clinically realistic data based on GBM patients. Two algorithms are used for specific RF energy absorption rate based thermal intervention planning for small and large TVs in the brain, aiming at maximum RF power deposition or RF power uniformity in the TV for 10 RF applicator designs.Results: For both TVs , the power optimization outperformed the uniformity optimization. The best results for the small TV are obtained for the 16 element interleaved RF applicator using an elliptical antenna arrangement with water bolus. The two row elliptical RF applicator yielded the best result for the large TV.Discussion: This work investigates the capacity of ThermalMR to achieve targeted thermal interventions in model systems resembling human brain tissue and brain tumors.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Glioblastoma/diagnóstico por imagem , Glioblastoma/terapia , Imageamento por Ressonância Magnética/métodos , Ablação por Radiofrequência/métodos , Humanos
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