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1.
Nucleic Acids Res ; 50(10): 5726-5738, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35640616

RESUMO

The structure and properties of DNA depend on the environment, in particular the ion atmosphere. Here, we investigate how DNA twist -one of the central properties of DNA- changes with concentration and identity of the surrounding ions. To resolve how cations influence the twist, we combine single-molecule magnetic tweezer experiments and extensive all-atom molecular dynamics simulations. Two interconnected trends are observed for monovalent alkali and divalent alkaline earth cations. First, DNA twist increases monotonously with increasing concentration for all ions investigated. Second, for a given salt concentration, DNA twist strongly depends on cation identity. At 100 mM concentration, DNA twist increases as Na+ < K+ < Rb+ < Ba2+ < Li+ ≈ Cs+ < Sr2+ < Mg2+ < Ca2+. Our molecular dynamics simulations reveal that preferential binding of the cations to the DNA backbone or the nucleobases has opposing effects on DNA twist and provides the microscopic explanation of the observed ion specificity. However, the simulations also reveal shortcomings of existing force field parameters for Cs+ and Sr2+. The comprehensive view gained from our combined approach provides a foundation for understanding and predicting cation-induced structural changes both in nature and in DNA nanotechnology.


Assuntos
DNA , Simulação de Dinâmica Molecular , Cátions , Cátions Bivalentes , Cátions Monovalentes , DNA/química , Sódio , Cloreto de Sódio
2.
Oncology ; 98(1): 53-60, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31578019

RESUMO

INTRODUCTION: The present study evaluated the potential benefit of adding cetuximab to neoadjuvant, adjuvant, or palliative standard therapy for pancreatic cancer. METHODS: A systematic literature search was performed in MEDLINE, Web of Science, and Cochrane Central Register of Controlled Trials (CENTRAL). Only randomised controlled trials (RCTs) investigating the effect of adding cetuximab to standard chemotherapy in pancreatic cancer were included. Evaluated outcomes were overall survival, progression-free survival, objective response, and toxicity. For overall survival and progression-free survival, hazard ratios (HR) with 95% confidence intervals (CI) were chosen as effect measure. For objective response, odds ratios (OR) with 95% CI were used. Analysis was based on a random effects model. RESULTS: After screening 568 publications, a total of 4 RCTs with 924 patients were included. In all trials, patients were adequately randomised with balanced intervention and control groups. There was no significant difference in overall survival (HR 1.04; 95% CI: 0.90-1.19; p = 0.60), progression-free survival (HR 1.06; 95% CI: 0.93-1.22; p = 0.36), or objective response (OR 0.99; 95% CI: 0.66 -1.49; p = 0.96) when adding cetuximab to a standard therapy. Toxicity was the same or higher in each of the included trials. According to GRADE, the certainty of the evidence is high. Therefore, adding cetuximab to pancreatic cancer therapy has no clinically relevant benefit. CONCLUSION: In the presence of no survival benefit, increased toxicity, and higher costs, a decreased cost-benefit ratio compared to the standard care must be suggested. Conducting further RCTs in unselected pancreatic cancer populations is unlikely to change this conclusion.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Cetuximab/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Cetuximab/administração & dosagem , Cetuximab/efeitos adversos , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidade , Prognóstico , Resultado do Tratamento
3.
J Neurooncol ; 147(3): 607-618, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32239433

RESUMO

INTRODUCTION: Stereotactic radiosurgery (SRS) is an emerging treatment for patients with multiple brain metastases (BM). The present work compares the SRS of multiple brain metastases with whole-brain radiotherapy (WBRT). METHODS: We performed a matched-pair analysis for 128 patients with multiple BM treated with either SRS or WBRT over a 5-year period. Patients were matched pairwise for seven potential prognostic factors. A mixed Cox Proportional Hazards model with univariate and multivariate analysis was fitted for overall survival (OS). Distant intracranial progression-free survival (icPFS) and local control were assessed using a Fine and Gray subdistribution hazard model and considering death as competing event. RESULTS: Patients undergoing SRS had a median of 4 BM (range 3-16). 1-year local control of individual BM following SRS was 91.7%. Median OS in the SRS subgroup was 15.7 months (IQR 9.7-36.4) versus 8.0 months (interquartile range, IQR 3.8-18.0) in the WBRT subgroup (HR 2.25, 95% CI [1.5; 3.5], p < 0.001). Median icPFS was 8.6 (IQR 3.4-18.0) versus 22.4 (IQR 5.6-28.6) months, respectively (HR for WBRT 0.41, 95% CI [0.24; 0.71], p = 0.001). Following SRS, synchronous BM diagnosis (HR 2.51, 95% CI [1.30; 4.70], p = 0.004), higher initial number of BM (HR 1.21, 95% CI [1.10; 1.40], p = 0.002) and lung cancer histology (HR 2.05, 95% CI [1.10; 3.80], p = 0.024) negatively impacted survival. Excellent clinical performance (KPI 90%) was a positive prognosticator (HR 0.38, 95% CI [0.20; 0.72], p = 0.003), as was extracerebral tumor control (HR 0.48, 95% CI [0.24; 0.97], p = 0.040). Higher initial (HR 1.19, 95% CI [1.00; 1.40], p < 0.013) and total number of BM (HR 1.23, 95% CI [1.10; 1.40], p < 0.001) were prognostic for shorter icPFS. CONCLUSION: This is the first matched-pair analysis to compare SRS alone versus WBRT alone for multiple BM. OS was prolonged in the SRS subgroup and generally favorable in the entire cohort. Our results suggest SRS as a feasible and effective treatment for patients with multiple BM.


Assuntos
Neoplasias Encefálicas/radioterapia , Radiocirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Irradiação Craniana/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Retrospectivos , Adulto Jovem
4.
Ann Surg Oncol ; 26(9): 2759-2767, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31115853

RESUMO

BACKGROUND: The BREAST-Q is a patient-reported outcome measure to evaluate satisfaction and health-related quality of life (HRQOL) after breast surgery. The aim of this study is to test the acceptability, reliability, and validity of the most recently developed BREAST-Q module for breast-conserving therapy (BCT) in a prospective clinical cohort. METHODS: The BREAST-Q BCT module was translated into German according to international guidelines. A total of 253 women with primary breast cancer undergoing BCT were recruited preoperatively. This study evaluated the BREAST-Q BCT subscales by using psychometric methods including acceptability, reliability, and validity. To examine construct validity, convergent and discriminant validity were determined by testing the instrument's scales against the EORTC C30 and BR23 as reference questionnaires. RESULTS: Acceptability was supported by a high follow-up rate (90%) and low frequency of missing data (< 10%) in all but three scales. Scale reliability was supported by high Cronbach's alpha coefficients (> 0.86) and item-total correlations (range of means, 0.33-0.89). Validity was shown by convergent and divergent correlations. The hypotheses of relationships between the scales of the BREAST-Q and the EORTC QLQ C30 BR23 revealed moderate to high correlations. CONCLUSIONS: The BREAST-Q BCT module proved to be an accepted, reliable, and valid questionnaire for the assessment of HRQOL and patient satisfaction after BCT in breast cancer patients. It can be recommended as a possible standard PROM for individual clinical analysis, quality assessment, and future trials.


Assuntos
Neoplasias da Mama/psicologia , Mastectomia Segmentar/psicologia , Medidas de Resultados Relatados pelo Paciente , Satisfação do Paciente , Qualidade de Vida/psicologia , Neoplasias da Mama/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
5.
Cell Physiol Biochem ; 38(5): 1883-96, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27160591

RESUMO

BACKGROUND/AIMS: Embryonic stem (ES) cells have got a broad range differentiation potential. The differentiation is initiated via aggregation of non-differentiated ES cells into embryoid body (EB) capable of multi-lineage development. However experimental variables present in standard differentiation techniques lead to high EB heterogeneity, affecting development into the cells of desired lineage, and do not support the process automatization and scalability. METHODS: Here we present a novel pipe based microbioreactor (PBM) setup based on segmented flow, designed for spatial maintenance of temperature, nutrition supply, gas supply and sterility. RESULTS: We verified PBM feasibility for continuous process generating cardiac cells starting from single ES cell suspension followed by EB formation for up to 10 days. The ES cells used in the study were genetically modified for cardiac-specific EGFP expression allowing optical monitoring of cardiomyocytes while EBs remained within PBM for up to 10 days. Efficiency of cardiac cells formation within PBM was similar compared to a standard hanging drop based protocol. CONCLUSION: Our findings ensure further development of microfluidic bioreactor technology to enable robust cardiomyocytes production for needs of drug screening, tissue engineering and other applications.


Assuntos
Técnicas de Cultura de Células/métodos , Células-Tronco Embrionárias Murinas/citologia , Miócitos Cardíacos/citologia , Animais , Reatores Biológicos , Técnicas de Cultura de Células/instrumentação , Diferenciação Celular , Linhagem Celular , Citometria de Fluxo , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/metabolismo , Camundongos , Microfluídica/instrumentação , Microfluídica/métodos , Microscopia , Células-Tronco Embrionárias Murinas/metabolismo , Miócitos Cardíacos/metabolismo , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , RNA Mensageiro/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Engenharia Tecidual
6.
Technol Cancer Res Treat ; 23: 15330338241252622, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38845139

RESUMO

Purpose: The aim of this matched-pair cohort study was to evaluate the potential of intensity-modulated proton therapy (IMPT) for sparring of the pelvic bone marrow and thus reduction of hematotoxicity compared to intensity-modulated photon radiotherapy (IMRT) in the setting of postoperative irradiation of gynaecological malignancies. Secondary endpoint was the assessment of predictive parameters for the occurrence of sacral insufficiency fractures (SIF) when applying IMPT. Materials and Methods: Two cohorts were analyzed consisting of 25 patients each. Patients were treated with IMPT compared with IMRT and had uterine cervical (n = 8) or endometrial cancer (n = 17). Dose prescription, patient age, and diagnosis were matched. Dosimetric parameters delivered to the whole pelvic skeleton and subsites (ilium, lumbosacral, sacral, and lower pelvis) and hematological toxicity were evaluated. MRI follow-up for evaluation of SIF was only available for the IMPT group. Results: In the IMPT group, integral dose to the pelvic skeleton was significantly lower (23.4GyRBE vs 34.3Gy; p < 0.001), the average V5Gy, V10Gy, and V20Gy were reduced by 40%, 41%, and 28%, respectively, compared to the IMRT group (p < 0.001). In particular, for subsites ilium and lower pelvis, the low dose volume was significantly lower. Hematotoxicity was significantly more common in the IMRT group (80% vs 32%; p = 0009), especially hematotoxicity ≥ CTCAE II (36% vs 8%; p = 0.037). No patient in the IMPT group experienced hematotoxicity > CTCAE II. In the IMPT cohort, 32% of patients experienced SIF. Overall SIF occurred more frequently with a total dose of 50.4 GyRBE (37.5%) compared to 45 GyRBE (22%). No significant predictive dose parameters regarding SIF could be detected aside from a trend regarding V50Gy to the lumbosacral subsite. Conclusion: Low-dose exposure to the pelvic skeleton and thus hematotoxicity can be significantly reduced by using IMPT compared to a matched photon cohort. Sacral insufficiency fracture rates appear similar to reported rates for IMRT in the literature.


Assuntos
Medula Óssea , Neoplasias dos Genitais Femininos , Terapia com Prótons , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada , Humanos , Feminino , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Terapia com Prótons/efeitos adversos , Terapia com Prótons/métodos , Medula Óssea/efeitos da radiação , Medula Óssea/patologia , Pessoa de Meia-Idade , Idoso , Neoplasias dos Genitais Femininos/radioterapia , Adulto , Planejamento da Radioterapia Assistida por Computador , Órgãos em Risco/efeitos da radiação , Tratamentos com Preservação do Órgão/métodos
7.
Nat Commun ; 15(1): 37, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167667

RESUMO

The potential spin-triplet heavy-fermion superconductor UTe2 exhibits signatures of multiple distinct superconducting phases. For field aligned along the b axis, a metamagnetic transition occurs at µ0Hm ≈ 35 T. It is associated with magnetic fluctuations that may be beneficial for the field-reinforced superconductivity surviving up to Hm. Once the field is tilted away from the b towards the c axis, a reentrant superconducting phase emerges just above Hm. In order to better understand this remarkably field-resistant superconducting phase, we conducted magnetic-torque and magnetotransport measurements in pulsed magnetic fields. We determine the record-breaking upper critical field of µ0Hc2 ≈ 73 T and its evolution with angle. Furthermore, the normal-state Hall effect experiences a drastic suppression indicative of a reduced band polarization above Hm in the angular range around 30° caused by a partial compensation between the applied field and an exchange field. This promotes the Jaccarino-Peter effect as a likely mechanism for the reentrant superconductivity above Hm.

8.
Cancers (Basel) ; 16(2)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38254756

RESUMO

Our study aims to identify the risk factors and dosimetry characteristics associated with capsular contracture. METHODS: We retrospectively analyzed 118 women with breast cancer who underwent PMRT following an IBR between 2010 and 2022. Patients were treated with PMRT of 50.0-50.4 Gy in 25-28 fractions. Capsular contracture was categorized according to the Baker Classification for Reconstructed Breasts. RESULTS: After a median follow-up of 22 months, the incidence of clinically relevant capsular contracture (Baker III-IV) was 22.9%. Overall, capsular contracture (Baker I-IV) occurred in 56 patients (47.5%) after a median of 9 months after PMRT. The rate of reconstruction failure/implant loss was 25.4%. In the univariate analysis, postoperative complications (prolonged pain, prolonged wound healing, seroma and swelling) and regional nodal involvement were associated with higher rates of capsular contracture (p = 0.017, OR: 2.5, 95% CI: 1.2-5.3 and p = 0.031, respectively). None of the analyzed dosimetric factors or the implant position were associated with a higher risk for capsular contracture. CONCLUSION: Postoperative complications and regional nodal involvement were associated with an increased risk of capsular contracture following breast reconstruction and PMRT, while none of the analyzed dosimetric factors were linked to a higher incidence. Additional studies are needed to identify further potential risk factors.

9.
Int J Radiat Oncol Biol Phys ; 116(4): 825-836, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36642110

RESUMO

PURPOSE: The APROVE study is a prospective one-arm phase-2 study investigating the safety and treatment tolerability of postoperative proton beam therapy in women with uterine cervical or endometrial cancer. In this analysis, we report the primary study endpoint of safety and treatment tolerability as well as toxicity rates and progression-free survival (PFS). METHODS AND MATERIALS: 25 patients were treated with postoperative proton beam therapy with a total dose of 45 to 50.4 Gy (RBE) in 5 to 6 × 1.8 Gy (RBE) fractions weekly using active raster-scanning intensity modulated proton beam therapy (IMPT). Sequential or simultaneous platinum-based chemotherapy was administered if indicated. The primary endpoint was defined as the lack of any acute ≥grade 3 gastrointestinal (GI) or urogenital (GU) toxicity according to the Common Terminology Criteria for Adverse Events v 4.0 or premature treatment abortion. Secondary endpoints were clinical symptoms and toxicity, quality of life, and PFS. RESULTS: All patients completed IMPT according to the protocol, with a median treatment duration of 43 days (range, 33 to 51 days). No patient developed gastrointestinal or genitourinary toxicity ≥grade 3, and the treatment tolerability rate was 100%. Therefore, the null hypothesis H0: Tolerability Rate ≤80% could be rejected in favor of the alternative hypothesis H1: Tolerability rate >80% using an exact binomial test with a one-sided significance level of α = 10% (one-sided P value P = .0059). The median follow-up time after the end of IMPT was 25.1 months (range, 20.2 to 50.3 months). 18 of 25 (75%) patients completed the study follow-up of 24 months. 7 patients had progressive disease. Kaplan-Meier-estimated mean PFS was 39.9 months (95% confidence interval: 33.37 to 46.5 months). CONCLUSIONS: Postoperative IMPT is a safe treatment option for cervical and endometrial cancer patients, with only low-grade acute and late toxicities. Larger randomized trials are necessary to further assess the potential of IMPT and improve patient selection.


Assuntos
Neoplasias do Endométrio , Neoplasias dos Genitais Femininos , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Feminino , Terapia com Prótons/efeitos adversos , Terapia com Prótons/métodos , Neoplasias dos Genitais Femininos/tratamento farmacológico , Neoplasias dos Genitais Femininos/radioterapia , Qualidade de Vida , Estudos Prospectivos , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
10.
Radiat Oncol ; 18(1): 5, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624483

RESUMO

INTRODUCTION: The APROVE-trial investigated the tolerability of postoperative proton beam therapy in women with cervical or endometrial cancer. The present analysis evaluated the secondary endpoints of health-related quality of life (HRQOL) and patient-reported symptoms. METHODS: 25 patients were included in this prospective phase-II-trial and treated with postoperative radiotherapy using protons alone or in combination with chemotherapy. To attain general and gynecologic-specific HRQOL measures, the EORTC-QLQ-C30 questionnaires combined with -QLQ-CX24 for cervical and -QLQ-EN24 for endometrial cancer were assessed at baseline, at the end of RT and up to 2 years after radiotherapy. The results were compared to an age-matched norm reference population. Symptoms were assessed using Common Terminology Criteria for Adverse Events (CTCAE) and institutional patient-reported symptoms grading. RESULTS: Scores regarding global health status were markedly impaired at baseline (mean: 58.0 ± 20.1) compared to reference population data, but significantly (p = 0.036) improved and evened out to comparable norm values 2 years after proton therapy (mean: 69.9 ± 19.3). Treatment caused acute and long-term worsening of pain (p = 0.048) and gastrointestinal symptoms (p = 0.016) for women with endometrial cancer, but no higher-grade CTCAE ≥ 3° toxicity was observed. Dosimetric evaluation of rectum, sigmoid, large and small bowel showed no correlation with the reported gastrointestinal symptoms. After 2 years, fatigue had significantly improved (p = 0.030), whereas patients with cervical cancer experienced more often lymphedema (p = 0.017). Scores for endometrial cancer pertaining to sexual activity (p = 0.048) and body image (p = 0.022) had improved post treatment; in the latter this effect persisted after 2 years. CONCLUSION: Proton beam therapy in the adjuvant setting was well tolerated with only low-grade side effects concerning gastrointestinal symptoms, lymphedema and pain. Overall quality of life was impaired at baseline, but patients were able to recover to values comparable to norm population 2 years after proton therapy. Larger studies are needed to confirm whether the benefit of proton therapy translates into a clinical effect. Sexual dysfunction remains an important issue. TRIAL REGISTRATION: The trial was registered at https://clinicaltrials.gov (ClinicalTrials.gov Identifier: NCT03184350, 09th June 2017).


Assuntos
Neoplasias do Endométrio , Gastroenteropatias , Feminino , Humanos , Qualidade de Vida , Prótons , Estudos Prospectivos , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia , Dor , Medidas de Resultados Relatados pelo Paciente
11.
Technol Cancer Res Treat ; 22: 15330338231164537, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37038619

RESUMO

Objective: Women with locally advanced breast cancer (LABC) or inoperable local recurrence often suffer from a significantly reduced quality of life (QOL) due to local tumor-associated pain, bleeding, exulceration, or malodorous discharge. We aimed to further investigate the benefit of radiotherapy (RT) for symptom relief while weighing the side-effects. Materials and methods: Patients who received symptom-oriented RT for palliative therapy of their LABC or local recurrence in the Department of Radiation Oncology at Heidelberg University Hospital between 2012 and 2021 were recorded. Clinical, pathological, and therapeutic data were collected and the oncological and symptomatic responses as well as therapy-associated toxicities were analyzed. Results: We retrospectively identified 26 consecutive women who received palliative RT with a median total dose of 39 Gy or single dose of 3 Gy in 13 fractions due to (impending) exulceration, pain, local hemorrhage, and/or vascular or plexus compression. With a median follow-up of 6.5 months after initiation of RT, overall survival at 6 and 12 months was 60.0% and 31.7%, and local control was 75.0% and 47.6%, respectively. Radiation had to be discontinued in 4 patients due to oncological clinical deterioration or death. When completed as initially planned, symptom improvement was achieved in 95% and WHO level reduction of analgesics in 28.6% of patients. In 36% (16%) of patients, local RT had already been indicated >3 months (>6 months) before the actual start of RT, but was delayed or not initiated among others in favor of drug alternatives or systemic therapies. RT-associated toxicities included only low-grade side-effects (CTCAE I°-II°) with predominantly skin erythema and fatigue even in the context of re-RT. Conclusion: Palliative RT in symptomatic LABC or locoregional recurrence is an effective treatment option for controlling local symptoms with only mild toxicity. It may thus improve QOL and should be considered early in palliative patient care management.


Assuntos
Neoplasias da Mama , Cuidados Paliativos , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/patologia , Qualidade de Vida , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia , Radioterapia
12.
Clin Transl Radiat Oncol ; 39: 100567, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36935853

RESUMO

Purpose/Objective: To evaluate the potential of stereotactic magnetic resonance-guided online adaptive radiotherapy (SMART) to fulfill dose recommendations for stereotactic body radiotherapy (SBRT) of adrenal metastases and spare organs at risk (OAR). Materials and methods: In this subgroup analysis of a prospective registry trial, 22 patients with adrenal metastases were treated on a 0.35 T MR-Linac in 5-12 fractions with fraction doses of 4-10 Gy. Baseline plans were re-calculated to the anatomy of the day. These predicted plans were reoptimized to generate adapted plans. Baseline, predicted and adapted plans were compared with regard to PTV objectives, OAR constraints and published dose recommendations. Results: The cohort comprised patients with large GTV (median 36.0 cc) and PTV (median 66.6 cc) and predominantly left-sided metastases. 179 of 181 fractions (98.9 %) were adapted because of PTV and/or OAR violations. Predicted plans frequently violated PTV coverage (99.4 %) and adjacent OAR constraints (bowel: 32.9 %, stomach: 32.8 %, duodenum: 10.4 %, kidneys: 10.8 %). In the predicted plans, the volume exposed to the maximum dose was exceeded up to 16-fold in the duodenum and up to 96-fold in the spinal cord. Adapted plans significantly reduced OAR violations by 96.4 % for the bowel, 98.5 % for the stomach, 85.6 % for the duodenum and 83.3 % for the kidneys. Plan adaptation improved PTV coverage from 82.7 ± 8.1 % to 90.6 ± 4.9 % (p < 0.001). Furthermore, recently established target volume thresholds could easily be fulfilled with SMART. No toxicities > grade II occurred. Conclusion: SMART fulfills established GTV and PTV dose recommendations while simultaneously sparing organs at risk even in a challenging cohort.

13.
Int J Radiat Oncol Biol Phys ; 117(4): 857-868, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37244626

RESUMO

PURPOSE: The IMRT-MC2 trial was conducted to demonstrate the noninferiority of conventionally fractionated intensity modulated radiation therapy with a simultaneous integrated boost to 3-dimensional conformal radiation therapy with a sequential boost for adjuvant breast radiation therapy. METHODS AND MATERIALS: A total of 502 patients were randomized between 2011 and 2015 for the prospective, multicenter, phase III trial (NCT01322854). Five-year results of late toxicity (late effects normal tissue task force-subjective, objective, management, and analytical), overall survival, disease-free survival, distant disease-free survival, cosmesis (Harvard scale), and local control (noninferiority margin at hazard ratio [HR] of 3.5) were analyzed after a median follow-up of 62 months. RESULTS: The 5-year local control rate for the intensity modulated radiation therapy with simultaneous integrated boost arm was non-inferior to the control arm (98.7% vs 98.3%, respectively; HR, 0.582; 95% CI, 0.119-2.375; P = .4595). Furthermore, there was no significant difference in overall survival (97.1% vs 98.3%, respectively; HR, 1.235; 95% CI, 0.472-3.413; P = .6697), disease-free survival (95.8% vs 96.1%, respectively; HR, 1.130; 95% CI, 0.487-2.679; P = .7758), and distant disease-free survival (97.0% vs 97.8%, respectively; HR, 1.667; 95% CI, 0.575-5.434; P = .3601). After 5 years, late toxicity evaluation and cosmetic assessment further showed no significant differences between treatment arms. CONCLUSIONS: The 5-year results of the IMRT-MC2 trial provide strong evidence that the application of conventionally fractionated simultaneous integrated boost irradiation for patients with breast cancer is both safe and effective, with noninferior local control compared with 3-dimensional conformal radiation therapy with sequential boost.

14.
Cancers (Basel) ; 14(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36551527

RESUMO

(1) Background: To assess dosimetry benefits of stereotactic magnetic resonance (MR)-guided online adaptive radiotherapy (SMART) of liver metastases. (2) Methods: This is a subgroup analysis of an ongoing prospective registry including patients with liver metastases. Patients were treated at the MRIdian Linac between February 2020 and April 2022. The baseline plan was recalculated based on the updated anatomy of the day to generate the predicted plan. This predicted plan could then be re-optimized to create an adapted plan. (3) Results: Twenty-three patients received 30 SMART treatment series of in total 36 liver metastases. Most common primary tumors were colorectal- and pancreatic carcinoma (26.1% respectively). Most frequent fractionation scheme (46.6%) was 50 Gy in five fractions. The adapted plan was significantly superior compared to the predicted plan in regard to planning-target-volume (PTV) coverage, PTV overdosing, and organs-at-risk (OAR) dose constraints violations (91.5 vs. 38.0%, 6 vs. 19% and 0.6 vs. 10.0%; each p < 0.001). Plan adaptation significantly increased median BEDD95 by 3.2 Gy (p < 0.001). Mean total duration of SMART was 72.4 min. (4) Conclusions: SMART offers individualized ablative irradiation of liver metastases tailored to the daily anatomy with significant superior tumor coverage and improved sparing of OAR.

15.
Cancers (Basel) ; 14(12)2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35740675

RESUMO

The present analysis compares the esthetics assessment by the BCCT.core software in relation to patients' and physicians' ratings, based on the IMRT-MC2 trial. Within this trial, breast cancer patients received breast-conserving surgery (BCS) and adjuvant radiotherapy. At the baseline, 6 weeks, and 2 years after radiotherapy, photos of the breasts were assessed by the software and patients' and physicians' assessments were performed. Agreement rates of the assessments and their correlation with breast asymmetry indices were evaluated. The assessments of the software and the physicians were significantly correlated with asymmetry indices. Before and 6 weeks after radiotherapy, the patients' self-assessment was only correlated with the lower breast contour (LBC) and upward nipple retraction (UNR), while after 2 years, there was also a correlation with other indices. Only a slight agreement between the BCCT.core software and the physicians' or patients' assessment was seen, while a moderate and substantial agreement was detected between the physicians' and the patients' assessment after 6 weeks and 2 years, respectively. The BCCT.core software is a reliable tool to measure asymmetries, but may not sufficiently evaluate the esthetic outcome as perceived by patients. It may be more appropriate for a long-term follow-up, when symmetry appears to increase in importance.

16.
Adv Mater ; 34(42): e2204038, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35829689

RESUMO

Polyhydrides are a novel class of superconducting materials with extremely high critical parameters, which is very promising for sensor applications. On the other hand, a complete experimental study of the best so far known superconductor, lanthanum superhydride LaH10 , encounters a serious complication because of the large upper critical magnetic field HC2 (0), exceeding 120-160 T. It is found that partial replacement of La atoms by magnetic Nd atoms results in significant suppression of superconductivity in LaH10 : each at% of Nd causes a decrease in TC by 10-11 K, helping to control the critical parameters of this compound. Strong pulsed magnetic fields up to 68 T are used to study the Hall effect, magnetoresistance, and the magnetic phase diagram of ternary metal polyhydrides for the first time. Surprisingly, (La,Nd)H10 demonstrates completely linear HC2 (T) âˆ |T - TC |, which calls into question the applicability of the Werthamer-Helfand-Hohenberg model for polyhydrides. The suppression of superconductivity in LaH10 by magnetic Nd atoms and the robustness of TC with respect to nonmagnetic impurities (e.g., Y, Al, C) under Anderson's theorem gives new experimental evidence of the isotropic (s-wave) character of conventional electron-phonon pairing in lanthanum decahydride.

17.
Int J Radiat Oncol Biol Phys ; 109(5): 1311-1324, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33321192

RESUMO

PURPOSE: In the modern era, improvements in radiation therapy techniques have paved the way for simultaneous integrated boost irradiation in adjuvant breast radiation therapy after breast conservation surgery. Nevertheless, randomized trials supporting the noninferiority of this treatment to historical standards of care approach are lacking. METHODS: A prospective, multicenter, randomized phase 3 trial (NCT01322854) was performed to analyze noninferiority of conventional fractionated intensity modulated radiation therapy with simultaneous integrated boost (IMRT-SIB) to 3-D conformal radiation therapy with sequential boost (3-D-CRT-seqB) for breast cancer patients. Primary outcomes were local control (LC) rates at 2 and 5 years (noninferiority margin at hazard ratio [HR] of 3.5) as well as cosmetic results 6 weeks and 2 years after radiation therapy (evaluated via photo documentation calculating the relative breast retraction assessment [pBRA] score [noninferiority margin of 1.25]). RESULTS: A total of 502 patients were randomly assigned from 2011 to 2015. After a median follow-up of 5.1 years, the 2-year LC for the IMRT-SIB arm was noninferior to the 3-D-CRT-seqB arm (99.6% vs 99.6%, respectively; HR, 0.602; 95% CI, 0.123-2.452; P = .487). In addition, noninferiority was also shown for cosmesis after IMRT-SIB and 3-D-CRT-seqB at both 6 weeks (median pBRA, 9.1% vs 9.1%) and 2 years (median pBRA, 10.4% vs 9.8%) after radiation therapy (95% CI, -0.317 to 0.107 %; P = .332). Cosmetic assessment according to the Harvard scale by both the patient and the treating physician as well as late-toxicity evaluation with the late effects normal tissues- subjective, objective, management, analytic criteria, a score for the evaluation of long-term adverse effects in normal tissue, revealed no significant differences between treatment arms. In addition, there was no difference in overall survival rates (99.6% vs 99.6%; HR, 3.281; 95% CI: -0.748 to 22.585; P = .148) for IMRT-SIB and 3-D-CRT-seqB, respectively. CONCLUSIONS: To our knowledge, this is the first prospective trial reporting the noninferiority of IMRT-SIB versus 3-D-CRT-seqB with respect to cosmesis and LC at 2 years of follow-up. This treatment regimen considerably shortens adjuvant radiation therapy times without compromising clinical outcomes.


Assuntos
Neoplasias da Mama/radioterapia , Radioterapia de Intensidade Modulada/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/efeitos da radiação , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Feminino , Seguimentos , Coração/efeitos da radiação , Humanos , Pulmão/efeitos da radiação , Mastectomia Segmentar , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Estudos Prospectivos , Radioterapia Adjuvante , Radioterapia Conformacional/métodos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
18.
Radiother Oncol ; 163: 165-176, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34480960

RESUMO

BACKGROUND: We recently published 2-year results of the prospective, randomized IMRT-MC2 trial, showing non-inferior local control and cosmesis in breast cancer patients after conventionally fractionated intensity-modulated radiotherapy with simultaneously integrated boost (IMRT-SIB), compared to 3D-conformal radiotherapy with sequential boost (3D-CRT-seqB). Here, we report on 2-year quality of life results. PATIENTS AND METHODS: 502 patients were enrolled and randomized to IMRT-SIB (50.4 Gy in 1.8 Gy fractions with a 64.4 Gy SIB to the tumor bed) or to 3D-CRT-seqB (50.4 Gy in 1.8 Gy fractions, followed by a sequential boost of 16 Gy in 2 Gy fractions). For quality of life (QoL) assessment, patients completed the QLQ-C30 and QLQ-BR23 questionnaires at baseline, 6 weeks and 2 years after radiotherapy. RESULTS: Significant differences between treatment arms were seen 6 weeks after radiotherapy for pain (22.3 points for IMRT vs. 27.0 points for 3D-CRT-seqB; p = 0.033) and arm symptoms (18.1 points for IMRT vs. 23.6 points for 3D-CRT-seqB; p = 0.013), both favoring IMRT-SIB. Compared to baseline values, both arms showed significant improvement in global score (IMRT: p = 0.009; 3D-CRT: p = 0.001) after 2 years, with slight deterioration on the role (IMRT: p = 0.008; 3-D-CRT: p = 0.001) and social functioning (IMRT: p = 0.013, 3D-CRT: p = 0.001) as well as the future perspectives scale (IMRT: p = 0.003; 3D-CRT: p = 0.0034). CONCLUSION: This is the first randomized phase III trial demonstrating that IMRT-SIB was associated with slightly superior QoL compared to 3-D-CRT-seqB. These findings further support the clinical implementation of SIB in adjuvant breast cancer treatment.


Assuntos
Neoplasias da Mama , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Neoplasias da Mama/radioterapia , Feminino , Humanos , Estudos Prospectivos , Qualidade de Vida , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
19.
Breast Care (Basel) ; 15(2): 136-147, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32398982

RESUMO

BACKGROUND: Breast-conserving therapy including lumpectomy and adjuvant whole breast irradiation (WBI) has become the standard therapy for early-stage breast cancer (EBC). Without WBI, the recurrence rate is significantly increased. However, when selecting patients at a low a priori risk of local recurrence only a small breast-cancer-specific mortality benefit, but no overall survival improvement, was detected for WBI. As most recurrences occur close to the lumpectomy cavity, accelerated partial breast irradiation (APBI) delivered exclusively to a limited volume of tissue around the initial lumpectomy site, has gained increased attention and is now discussed as an alternative to WBI for selected EBC patients. SUMMARY: Numerous techniques for APBI (interstitial brachytherapy, external beam-based APBI, intraoperative radiotherapy, MR-guided radiotherapy) allow treatment delivery in a shorter period of time, and radiation oncologists expect to further reduce side effects by using these new techniques, with improvements in cosmetics and quality of life. In this review, we aim to describe the existing evidence for the feasibility and effectiveness of different APBI techniques used in modern radiotherapy. KEY MESSAGES: APBI has provided outcomes similar to WBI combined with potentially reduced toxicity. While appropriate patient selection persists to be crucial for acceptable recurrence rates, the precise definition of patients suitable for APBI remains a matter of discussion. As long-term data are often still lacking, special attention should be paid to late side effects and long-term outcomes. Decision-making on appropriate treatment techniques should take into account not only local control rates, but also the impact on the patient's quality of life.

20.
Front Oncol ; 10: 1557, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014802

RESUMO

Purpose: Several prognostic indexes for overall survival (OS) after radiotherapy of brain metastases in breast cancer patients exist but are mainly validated for whole-brain radiotherapy or not specifically for breast cancer patients. To date, no such index provides information beyond mere OS. Methods: We retrospectively analyzed 95 breast cancer patients treated with stereotactic radiosurgery for 203 brain metastases. The Kaplan-Meier method with log-rank test was used to assess OS, local control (LC), distant cranial control (DCC), and extracranial control (EC). Cox regression was applied to detect prognostic outcome factors. A point scoring system was designed to stratify patients based on outcome. Nine established prognostic indexes were analyzed using the concordance index (c-index). Results: Two out of nine analyzed prognostic indexes for OS showed a significant c-index, the breast graded prognostic assessment (bGPA; 0.631; 95% CI, 0.514-0.748; p = 0.037) and the modified bGPA (mod-bGPA; 0.662; 95% CI, 0.547-0.777; p = 0.010). Significant results from multivariate analysis (Karnofsky Performance Score, Her2/neu receptor status, extracranial control) were used to generate a new point system: the breast cancer stereotactic radiotherapy score (bSRS), which discriminated three significantly different prognostic groups, for LC, DCC, EC, and OS, respectively. However, the c-index was only significant for OS (0.689; 95% CI, 0.577-0.802; p = 0.003). Conclusions: The new bSRS score was superior to the bGPA and mod-bGPA scores for prognosis of OS. The bSRS is easy to use and the first tool, which might also provide outcome assessment beyond mere OS. Future studies need to validate these findings.

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