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1.
Clin Transl Radiat Oncol ; 47: 100790, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38765202

RESUMEN

Background: The PRIDE trial (NOA-28; ARO-2024-01; AG-NRO-06; NCT05871021) is designed to determine whether a dose escalation with 75.0 Gy in 30 fractions can enhance the median overall survival (OS) in patients with methylguanine methyltransferase (MGMT) promotor unmethylated glioblastoma compared to historical median OS rates, while being isotoxic to historical cohorts through the addition of concurrent bevacizumab (BEV). To ensure protocol-compliant irradiation planning with all study centers, a dummy run was planned and the plan quality was evaluated. Methods: A suitable patient case was selected and the computed tomography (CT), magnetic resonance imaging (MRI) and O-(2-[18F]fluoroethyl)-L-tyrosine (FET) positron emission tomography (PET) contours were made available. Participants at the various intended study sites performed radiation planning according to the PRIDE clinical trial protocol. The treatment plans and dose grids were uploaded as Digital Imaging and Communications in Medicine (DICOM) files to a cloud-based platform. Plan quality and protocol adherence were analyzed using a standardized checklist, scorecards and indices such as Dice Score (DSC) and Hausdorff Distance (HD). Results: Median DSC was 0.89, 0.90, 0.88 for PTV60, PTV60ex (planning target volume receiving 60.0 Gy for the standard and the experimental plan, respectively) and PTV75 (PTV receiving 75.0 Gy in the experimental plan), respectively. Median HD values were 17.0 mm, 13.9 mm and 12.1 mm, respectively. These differences were also evident in the volumes: The PTV60 had a volume range of 219.1-391.3 cc (median: 261.9 cc) for the standard plans, while the PTV75 volumes for the experimental plans ranged from 71.5-142.7 cc (median: 92.3 cc). The structures with the largest deviations in Dice score were the pituitary gland (median 0.37, range 0.00-0.69) and the right lacrimal gland (median 0.59, range 0.42-0.78). Conclusions: The deviations revealed the necessity of systematic trainings with appropriate feedback before the start of clinical trials in radiation oncology and the constant monitoring of protocol compliance throw-out the study. Trial registration: NCT05871021.

2.
Clin Transl Radiat Oncol ; 45: 100706, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38116137

RESUMEN

Background and purpose: The PRIDE trial (NOA-28; ARO-2022-12; NCT05871021) is scheduled to start recruitment in October 2023. Its primary objective is to enhance median overall survival (OS), compared to historical median OS rates, in patients with methylguanine methlyltransferase (MGMT) promotor unmethylated glioblastoma by incorporating isotoxic dose escalation to 75 Gy in 30 fractions. To achieve isotoxicity and counteract the elevated risk of radiation necrosis (RN) associated with dose-escalated regimens, the addition of protective concurrent bevacizumab (BEV) serves as an innovative approach. The current study aims to assess the dosimetric feasibility of the proposed concept. Materials and methods: A total of ten patients diagnosed with glioblastoma were included in this dosimetric analysis. Delineation of target volumes for the reference plans adhered to the ESTRO-EANO 2023 guideline. The experimental plans included an additional volume for the integrated boost. Additionally, the 60 Gy-volume was reduced by using a margin of 1.0 cm instead of 1.5 cm. To assess the risk of symptomatic RN, the Normal Tissue Complication Probability (NTCP) was calculated and compared between the reference and experimental plans. Results: Median NTCP of the reference plan (NTCPref) and of the experimental plan (NTCPex) were 0.24 (range 0.11-0.29) and 0.42 (range 0.18-0.54), respectively. NTCPex was a median of 1.77 (range 1.60-1.99) times as high as the NTXPref. In a logarithmic comparison, the risk of RN is enhanced by a factor of median 2.00 (range 1.66-2.35). The defined constraints for the organs at risk were feasible. Conclusion: When considering the potential protective effect of BEV, which we hypothesized might reduce the risk of RN by approximately two-fold, achieving isotoxicity with the proposed dose-escalated experimental plan for the PRIDE trial seems feasible.

3.
Cancers (Basel) ; 15(8)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37190263

RESUMEN

We aimed to evaluate the standard of care of adjuvant radiotherapy (RT) after breast-conserving surgery (BCS) in elderly female patients (≥65 years) treated outside of clinical trials and to identify potential factors related to the omission of RT and the interaction with endocrine therapy (ET). All women treated with BCS at two major breast centers between 1998 and 2014 were evaluated. Data were provided by the Tumor Registry Munich. Survival analyses were conducted using the Kaplan-Meier method. Prognostic factors were identified using multivariate Cox regression analysis. The median follow-up was 88.4 months. Adjuvant RT was performed in 82% (2599/3171) of patients. Irradiated patients were younger (70.9 vs. 76.5 years, p < 0.001) and were more likely to receive additional chemotherapy (p < 0.001) and ET (p = 0.014). Non-irradiated patients more often had non-invasive DCIS tumors (pTis: 20.3% vs. 6.8%, p < 0.001) and did not undergo axillary surgery (no axillary surgery: 50.5% vs. 9.5%, p < 0.001). Adjuvant RT was associated with improved locoregional tumor control after BCS in invasive tumors (10-year local recurrence-free survival (LRFS): 94.0% vs. 75.1%, p < 0.001, 10-year lymph node recurrence-free survival (LNRFS): 98.1% vs. 93.1%, p < 0.001). Multivariate analysis confirmed significant benefits for local control with postoperative RT. Furthermore, RT led to increased locoregional control even in patients who received ET (10-year LRFS 94.8% with ET + RT vs. 78.1% with ET alone, p < 0.001 and 10-year LNRFS: 98.2% vs. 95.0%, p = 0.003). Similarly, RT alone had significantly better locoregional control rates compared to ET alone (10-year LRFS 92.6% with RT alone vs. 78.1% with ET alone, p < 0.001 and 10-year LNRFS: 98.0% vs. 95.0%, p = 0.014). The present work confirms the efficacy of postoperative RT for breast carcinoma in elderly patients (≥65 years) treated in a modern clinical setting outside of clinical trials, even in patients who receive ET.

4.
Cancer ; 128(12): 2358-2366, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35417563

RESUMEN

BACKGROUND: The objective of this study was to investigate the feasibility and efficacy of image-guided moderately hypofractionated thoracic radiotherapy (hypo-IGRT) in patients with non-small cell lung cancer (NSCLC) with poor performance status and severely limited pulmonary function and reserve. METHODS: Consecutive inoperable patients who had node-positive, stage IIB-IIIC (TNM, 8th edition) or recurrent NSCLC, had an Eastern Cooperative Oncology Group performance status ≥1, and had a forced expiratory volume in 1 second (FEV1 ) ≤1.0 L, had a single-breath diffusing capacity of the lung for carbon monoxide (DLCO-SB) ≤40% and/or on long-term oxygen therapy were analyzed. All patients received hypofractionated IGRT to a total dose of 42.0 to 49.0 Gy/13 to 16 fractions (2.8-3.5 Gy/fraction) (equivalent dose in 2-Gy fractions/biologically effective dose [α/ß = 10] = 45.5-55.1 Gy/54.6-66.2 Gy) alone. Patients were monitored closely for nonhematological toxicity, which was classified per National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0. RESULTS: Between 2014 and 2021, 47 consecutive patients with a median age of 72 years (range, 52.2-88 years) were treated. At baseline, the median FEV1 , vital capacity, and DLCO-SB were 1.17 L (range, 0.69-2.84 L), 2.34 L (range, 1.23-3.74 L), and 35% predicted (range, 13.3%-69.0%), respectively. The mean and median planning target volumes were 410.8 cc (SD, 267.1 cc) and 315.4 cc (range, 83.4-1174.1 cc). With a median follow-up of 28.9 months (range, 0.5-90.6 months) after RT, the median progression-free survival (PFS)/overall survival (OS) and 6- and 12-month PFS/OS rates were 10.4 months (95% CI, 7-13.8 months)/18.3 months (95% CI, 9.2-27.4 months), 70%/89.4%, and 38.8%/66%, respectively. Treatment was well tolerated with only 1 case each of grade 3 pneumonitis and esophagitis. No toxicity greater than grade 3 was observed. CONCLUSIONS: Patients with inoperable node-positive NSCLC, a poor performance status, and severely limited lung function can be safely and effectively treated with individualized moderately hypofractionated IGRT. The achieved survival rates for this highly multimorbid group of patients were encouraging.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Humanos , Pulmón/efectos de la radiación , Neoplasias Pulmonares/radioterapia , Persona de Mediana Edad , Recurrencia Local de Neoplasia/radioterapia , Pronóstico
5.
Radiat Oncol ; 17(1): 8, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35033132

RESUMEN

BACKGROUND AND PURPOSE: Chemoradiotherapy (CRT) followed by a brachytherapy (BT) boost is the standard of care for patients with locally advanced or recurrent gynecological cancer (LARGC). However, not every patient is suitable for BT. Therefore, we investigated the feasibility of an MR-guided SBRT boost (MRg-SBRT boost) following CRT of the pelvis. MATERIAL AND METHODS: Ten patients with LARGC were analyzed retrospectively. The patients were not suitable for BT due to extensive infiltration of the pelvic wall (10%), other adjacent organs (30%), or both (50%), or ineligibility for anesthesia (10%). Online-adaptive treatment planning was performed to control for interfractional anatomical changes. Treatment parameters and toxicity were evaluated to assess the feasibility of MRg-SBRT boost. RESULTS: MRg-SBRT boost was delivered to a median total dose of 21.0 Gy in 4 fractions. The median optimized PTV (PTVopt) size was 43.5ccm. The median cumulative dose of 73.6Gy10 was delivered to PTVopt. The cumulative median D2ccm of the rectum was 63.7 Gy; bladder 72.2 Gy; sigmoid 65.8 Gy; bowel 59.9 Gy (EQD23). The median overall treatment time/fraction was 77 min, including the adaptive workflow in 100% of fractions. The median duration of the entire treatment was 50 days. After a median follow-up of 9 months, we observed no CTCAE ≥ °II toxicities. CONCLUSION: These early results report the feasibility of an MRg-SBRT boost approach in patients with LARGC, who were not candidates for BT. When classical BT-OAR constraints are followed, the therapy was well tolerated. Long-term follow-up is needed to validate the results.


Asunto(s)
Neoplasias de los Genitales Femeninos/radioterapia , Imagen por Resonancia Magnética , Radiocirugia/métodos , Radioterapia Guiada por Imagen , Adulto , Anciano , Anciano de 80 o más Años , Braquiterapia , Quimioradioterapia , Estudios de Factibilidad , Femenino , Neoplasias de los Genitales Femeninos/terapia , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Retrospectivos
6.
Proc Natl Acad Sci U S A ; 118(14)2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33782128

RESUMEN

The Invar anomaly is one of the most fascinating phenomena observed in magnetically ordered materials. Invariant thermal expansion and elastic properties have attracted substantial scientific attention and led to important technological solutions. By studying planar faults in the high-temperature magnetically disordered state of [Formula: see text], here we disclose a completely different anomaly. An invariant plastic deformation mechanism is characterized by an unchanged stacking fault energy with temperature within wide concentration and temperature ranges. This anomaly emerges from the competing stability between the face-centered cubic and hexagonal close-packed structures and occurs in other paramagnetic or nonmagnetic systems whenever the structural balance exists. The present findings create a platform for tailoring high-temperature properties of technologically relevant materials toward plastic stability at elevated temperatures.

7.
Radiat Oncol ; 15(1): 117, 2020 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-32448164

RESUMEN

BACKGROUND: Patients with left-sided breast cancer have an increased risk of cardiovascular disease (CVD) after radiotherapy (RT). While the awareness of cardiac toxicity has increased enormously over the last decade, the role of individual baseline cardiac risks has not yet been systematically investigated. Aim of the present study was to evaluate the impact of baseline CVD risks on radiation-induced cardiac toxicity. METHODS: Two hundred ten patients with left-sided breast cancer treated in the prospective Save-Heart Study using a deep inspiration breath-hold (DIBH) technique were analysed regarding baseline risk factors for CVD. Three frequently used prediction tools (Procam, Framingham and Reynolds score) were applied to evaluate the individual CVD risk profiles. Moreover, 10-year CVD excess absolute risks (EAR) were estimated using the individual mean heart dose (MHD) of treatment plans in free breathing (FB) and DIBH. RESULTS: The individual baseline CVD risk factors had a strong impact on the 10-year cumulative CVD risk. The mean baseline risks of the non-diabetic cohort (n = 200) ranged from 3.11 to 3.58%, depending on the risk estimation tool. A large number of the non-diabetic patients had a very low 10-year CVD baseline risk of ≤1%; nevertheless, 8-9% of patients reached ≥10% baseline 10-year CVD risk. In contrast, diabetic patients (n = 10) had significantly higher baseline CVD risks (range: 11.76-24.23%). The mean 10-year cumulative risk (Framingham score) following RT was 3.73% using the DIBH-technique (MHD:1.42Gy) and 3.94% in FB (MHD:2.33Gy), after adding a 10-year-EAR of + 0.34%(DIBH) and + 0.55%(FB) to the baseline risks, respectively. Smoking status was one of the most important and modifiable baseline risk factors. After DIBH-RT, the 182 non-smoking patients had a mean 10-year cumulative risk of 3.55% (3.20% baseline risk, 0.35% EAR) as compared to 6.07% (5.60% baseline risk, 0.47% EAR) for the 28 smokers. CONCLUSION: In the present study, all CVD prediction tools showed comparable results and could easily be integrated into daily clinical practice. A systematic evaluation and screening helps to identify high-risk patients who may benefit from primary prevention. This could result in an even higher benefit than from heart-sparing irradiation techniques alone.


Asunto(s)
Enfermedades Cardiovasculares , Corazón , Órganos en Riesgo , Radioterapia/efectos adversos , Neoplasias de Mama Unilaterales/radioterapia , Adulto , Enfermedades Cardiovasculares/epidemiología , Femenino , Corazón/efectos de la radiación , Humanos , Persona de Mediana Edad , Órganos en Riesgo/efectos de la radiación , Traumatismos por Radiación/epidemiología , Factores de Riesgo
8.
Radiat Oncol ; 15(1): 52, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32111228

RESUMEN

BACKGROUND: Three-dimensional Surface Imaging (3DSI) is a well-established method to objectively monitor morphological changes in the female breast in the field of plastic surgery. In contrast, in radiation oncology we are still missing effective tools, which can objectively and reproducibly assess and document adverse events in breast cancer radiotherapy within the framework of clinical studies. The aim of the present study was to apply structured-light technology as a non-invasive and objective approach for the documentation of cosmetic outcome and early effects of breast radiotherapy as a proof of principle. METHODS: Weekly 3DSI images of patients receiving either conventionally fractionated radiation treatment (CF-RT) or hypofractionated radiation treatment (HF-RT) were acquired during the radiotherapy treatment and clinical follow-up. The portable Artec Eva scanner (Artec 3D Inc., Luxembourg) recorded 3D surface images for the analysis of breast volumes and changes in skin appearance. Statistical analysis compared the impact of the two different fractionation regimens and the differences between the treated and the contralateral healthy breast. RESULTS: Overall, 38 patients and a total of 214 breast imaging sessions were analysed. Patients receiving CF-RT showed a significantly higher frequency of breast erythema compared to HF-RT (93.3% versus 34.8%, p = 0.003) during all observed imaging sessions. Moreover, we found a statistically significant (p < 0.05) volumetric increase of the treated breast of the entire cohort between baseline (379 ± 196 mL) and follow-up imaging at 3 months (437 ± 224 mL), as well as from week 3 of radiotherapy (391 ± 198 mL) to follow-up imaging. In both subgroups of patients undergoing either CF-RT or HF-RT, there was a statistically significant increase (p < 0.05) in breast volumes between baseline and 3 months follow-up. There were no statistically significant skin or volumetric changes of the untreated healthy breasts. CONCLUSIONS: This is the first study utilizing 3D structured-light technology as a non-invasive and objective approach for the documentation of patients receiving breast radiotherapy. 3DSI offers potential as a non-invasive tool to objectively and precisely monitor the female breast in a radiooncological setting, allowing clinicians to objectively distinguish outcomes of different therapy modalities.


Asunto(s)
Neoplasias de la Mama/radioterapia , Imagenología Tridimensional/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Persona de Mediana Edad , Hipofraccionamiento de la Dosis de Radiación
9.
Strahlenther Onkol ; 195(11): 964-971, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31332457

RESUMEN

OBJECTIVE: The impact of optical surface guidance on the use of portal imaging and the initial set-up duration in patients receiving postoperative radiotherapy of the breast or chest wall was investigated. MATERIAL AND METHODS: A retrospective analysis was performed including breast cancer patients who received postoperative radiotherapy between January 2016 and December 2016. One group of patients received treatment before the optical surface scanner was installed (no-OSS) and the other group was positioned using the additional information derived by the optical surface scanner (OSS). The duration of the initial set-up was recorded for each patient and a comparison of both groups was performed. Accordingly, the differences between planned and actually acquired portal images during the course of radiotherapy were compared between both groups. RESULTS: A total of 180 breast cancer patients were included (90 no-OSS, 90 OSS) in this analysis. Of these, 30 patients with left-sided breast cancer received radiotherapy in deep inspiration breath hold (DIBH). The mean set-up time was 10 min and 18 s and no significant difference between the two groups of patients was found (p = 0.931). The mean set-up time in patients treated without DIBH was 9 min and 45 s compared to 13 min with DIBH (p < 0.001), as portal imaging was performed in DIBH. No significant difference was found in the number of acquired to the planned number of portal images during the entire radiotherapy treatment for both groups (p = 0.287). CONCLUSION: Optical surface imaging is a valuable addition for primary patient set-up. The findings confirm that the addition of surface-based imaging did not prolong the clinical workflow and had no significant impact on the number of portal verification images carried out during the course of radiotherapy.


Asunto(s)
Posicionamiento del Paciente/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Adyuvante/métodos , Radioterapia Guiada por Imagen/métodos , Tomografía Óptica/métodos , Neoplasias de Mama Unilaterales/radioterapia , Terapia Combinada , Femenino , Humanos , Estudios Retrospectivos , Factores de Tiempo , Neoplasias de Mama Unilaterales/cirugía
10.
Cancers (Basel) ; 11(2)2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-30709048

RESUMEN

Although the organ preservation strategy by breast-conserving surgery (BCS) followed by radiation therapy (BCT) has revolutionized the treatment approach of early stage breast cancer (BC), the choice between treatment options in this setting can still vary according to patient preferences. The aim of the present study was to compare the oncological outcome of mastectomy versus breast-conserving therapy in patients treated in a modern clinical setting outside of clinical trials. 7565 women diagnosed with early invasive BC (pT1/2pN0/1) between 1998 and 2014 were included in this study (median follow-up: 95.2 months). In order to reduce selection bias and confounding, a subgroup analysis of a matched 1:1 case-control cohort consisting of 1802 patients was performed (median follow-up 109.4 months). After adjusting for age, tumor characteristics and therapies, multivariable analysis for local recurrence-free survival identified BCT as an independent predictor for improved local control (hazard ratio [HR]:1.517; 95%confidence interval:1.092⁻2.108, p = 0.013) as compared to mastectomy alone in the matched cohort. Ten-year cumulative incidence (CI) of lymph node recurrences was 2.0% following BCT, compared to 5.8% in patients receiving mastectomy (p < 0.001). Similarly, 10-year distant-metastasis-free survival (89.4% vs. 85.5%, p = 0.013) was impaired in patients undergoing mastectomy alone. This translated into improved survival in patients treated with BCT (10-year overall survival (OS) estimates 85.3% vs. 79.3%, p < 0.001), which was also significant on multivariable analysis (p = 0.011). In conclusion, the present study showed that patients treated with BCS followed by radiotherapy had an improved outcome compared to radical mastectomy alone. Specifically, local control, distant control, and overall survival were significantly better using the conservative approach. Thus, as a result of the present study, physicians should encourage patients to receive BCS with radiotherapy rather than mastectomy, whenever it is medically feasible and appropriate.

11.
Strahlenther Onkol ; 195(4): 289-296, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30046931

RESUMEN

BACKGROUND AND PURPOSE: Due to the rarity of male breast cancer (male BC), no consensus has been reached regarding the most appropriate curative treatment strategy. The objective of the present observational study was to identify patient and tumor characteristics and assess the role of radiotherapy (RT) in clinical practice. METHODS: Between 1998 and 2014, data of male BC patients treated at two breast centers were consecutively collected and retrospectively analyzed. Patients were stratified based on the addition of adjuvant RT. Data on overall survival (OS) and local recurrence-free survival (LRFS) were estimated with the Kaplan-Meier method and compared by the log-rank test. RESULTS: A consecutive cohort of 58 male BC patients was evaluated. Median follow-up was 56 months. Twenty-one patients (36.2%) received adjuvant RT. Overall, patients undergoing postoperative RT were characterized by more high-risk features. Patients receiving postoperative RT had significantly more frequently a high UICC stage (50 vs. 9.7% UICC III, p = 0.018) and positive lymph nodes as compared to patients undergoing surgery alone (65 vs. 34.4% pN+, p = 0.046). Accordingly, there was a higher proportion of patients receiving axillary lymph node dissection in the RT group (71.4 vs. 35.6%). Mastectomy was performed in 31/37 (86.1%) in the surgery group as compared to 14/21 (66.7%) in patients receiving postoperative RT. In addition, RT patients were more likely to receive endocrine therapy (78.9 vs. 39.3%, p = 0.016). Outcome was not significantly different between the groups (5-year LRFS: 89.8 vs. 80.0%, p = 0.471 and 5­year OS 88.4 vs. 88.9%, p = 0.819). CONCLUSION: The present observational study evaluated the pattern of care in male BC patients treated in clinical practice. Due to its rarity, randomized clinical trials are unlikely and male BC remains an entity with a poor evidence base. Nevertheless, RT remains a crucial component of the multidisciplinary treatment strategy in male BC.


Asunto(s)
Neoplasias de la Mama Masculina/radioterapia , Pautas de la Práctica en Medicina , Radioterapia Adyuvante , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama Masculina/mortalidad , Neoplasias de la Mama Masculina/patología , Terapia Combinada , Supervivencia sin Enfermedad , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática/patología , Masculino , Mastectomía , Persona de Mediana Edad , Recurrencia Local de Neoplasia/etiología , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Estudios Retrospectivos
12.
Radiother Oncol ; 131: 202-207, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30097250

RESUMEN

PURPOSE: Aim of the current comparative modelling study was to estimate the individual radiation-induced risk for death of ischaemic heart disease (IHD) under free breathing (FB) and deep inspiration breath-hold (DIBH) in a real-world population. MATERIALS AND METHODS: Eighty-nine patients with left-sided early breast cancer were enrolled in the prospective SAVE-HEART study. For each patient three-dimensional conformal treatment plans were created in FB and DIBH and corresponding radiation-induced risks of IHD mortality were estimated based on expected survival, individual IHD risk factors and the relative radiation-induced risk. RESULTS: With the use of DIBH, mean heart doses were reduced by 35% (interquartile range: 23-46%) as compared to FB. Mean expected years of life lost (YLL) due to radiation-induced IHD mortality were 0.11 years in FB, and 0.07 years in DIBH. YLL were remarkably independent of age at treatment in patients with a favourable tumour prognosis. DIBH led to more pronounced reductions in YLL in patients with high baseline risk (0.08 years for upper vs 0.02 years for lower quartile), with favourable tumour prognosis (0.05 years for patients without vs 0.02 years for those with lymph-node involvement), and in patients with high mean heart doses in FB (0.09 years for doses >3 Gy vs 0.02 years for doses <1.5 Gy). CONCLUSION: Ideally, the DIBH technique should be offered to all patients with left-sided breast cancer. However, highest benefits are expected for patients with a favourable tumour prognosis, high mean heart dose or high baseline IHD risk, independent of their age.


Asunto(s)
Contencion de la Respiración , Corazón/efectos de la radiación , Isquemia Miocárdica/etiología , Traumatismos por Radiación/etiología , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias de Mama Unilaterales/radioterapia , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Modelos Estadísticos , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/prevención & control , Estudios Prospectivos , Traumatismos por Radiación/epidemiología , Traumatismos por Radiación/prevención & control , Dosificación Radioterapéutica , Radioterapia Conformacional/métodos , Radioterapia de Intensidad Modulada/métodos , Riesgo
13.
Strahlenther Onkol ; 195(1): 13-20, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30143814

RESUMEN

PURPOSE: Aim of the present analysis was to evaluate the movement and dose variability of the different lymph node levels of node-positive breast cancer patients during adjuvant radiotherapy (RT) with regional nodal irradiation (RNI) in deep-inspiration breath hold (DIBH). METHODS: Thirty-five consecutive node-positive breast cancer patients treated from October 2016 to February 2018 receiving postoperative RT of the breast or chest wall including RNI of the supra-/infraclavicular lymph node levels (corresponding to levels IV, III, Rotter LN (interpectoral), and some parts of level II) were analyzed. To evaluate the lymph node level movement, a center of volume (COV) was obtained for each lymph node level for free-breathing (FB) and DIBH plans. Geometric shifts and dose differences between FB and DIBH were analyzed. RESULTS: A significant movement of the COV in anterior (y) and cranial (z) dimensions was observed for lymph node levels I-II and Rotter lymph nodes (p < 0.001) due to DIBH. Only minor changes in the lateral dimension (x axis) were observed, without reaching significance for levels III, IV, and internal mammary. There was a significant difference in the mean dose of level I (DIBH vs. FB: 38.2 Gy/41.3 Gy, p < 0.001) and level II (DIBH vs. FB: 45.9 Gy/47.2 Gy, p < 0.001), while there was no significant difference in level III (p = 0.298), level IV (p = 0.476), or internal mammary nodes (p = 0.471). CONCLUSION: A significant movement of the axillary lymph node levels was observed during DIBH in anterior and cranial directions for node-positive breast cancer patients in comparison to FB. The movement leads to a significant dose reduction in level I and level II.


Asunto(s)
Neoplasias de la Mama/radioterapia , Contencion de la Respiración , Carcinoma in Situ/radioterapia , Ganglios Linfáticos/efectos de la radiación , Metástasis Linfática/radioterapia , Dosificación Radioterapéutica , Radioterapia Conformacional , Adulto , Anciano , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Carcinoma in Situ/diagnóstico por imagen , Carcinoma in Situ/cirugía , Terapia Combinada , Femenino , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Metástasis Linfática/diagnóstico por imagen , Mastectomía Segmentaria , Persona de Mediana Edad , Estudios Prospectivos , Planificación de la Radioterapia Asistida por Computador , Radioterapia Adyuvante , Tomografía Computarizada por Rayos X
14.
Breast Care (Basel) ; 13(4): 285-291, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30319331

RESUMEN

Radiation therapy (RT) for breast cancer has dramatically changed over the past years, leading to individualized risk-adapted treatment strategies. Historically, the choice of RT regimen was limited to conventional fractionation protocols using standard tangential fields. Nowadays, technological and technical improvements in modern RT have added a variety of other RT modalities, different fractionation schedules, and individualised treatment volumes to the portfolio of breast RT. This review aims to give a short overview on the main topics which have recently found their way into clinical practice: hypofractionated treatment protocols, accelerated partial breast irradiation (APBI) for low-risk patients, deep inspiration breath hold (DIBH) for maximal heart protection, extent of regional nodal irradiation for high-risk patients, and the implementation of new radiation techniques such as intensity modulated RT (IMRT) and volumetric modulated RT (VMAT).

15.
Sci Rep ; 8(1): 12211, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-30111892

RESUMEN

High entropy alloys based on 3d transition metals display rich and promising magnetic characteristics for various high-technology applications. Understanding their behavior at finite temperature is, however, limited by the incomplete experimental data for single-phase alloys. Here we use first-principles alloy theory to investigate the magnetic structure of polymorphic CoCrFeMnNi in the paramagnetic state by accounting for the longitudinal spin fluctuations (LSFs) as a function of temperature. In both face-centered cubic (fcc) and hexagonal close-packed (hcp) structures, the LSFs induce sizable magnetic moments for Co, Cr and Ni. The impact of LSFs is demonstrated on the phase stability, stacking fault energy and the fcc-hcp interfacial energy. The hcp phase is energetically preferable to the fcc one at cryogenic temperatures, which results in negative stacking fault energy at these conditions. With increasing temperature, the stacking fault energy increases, suppressing the formation of stacking faults and nano-twins. Our predictions are consistent with recent experimental findings.

16.
Radiat Oncol ; 13(1): 25, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29426355

RESUMEN

BACKGROUND: The objective of the present study was to evaluate the effectiveness of postoperative radiotherapy after breast conserving surgery (BCS) in DCIS in a large patient population treated in clinical practice. METHODS: Data were provided by the population-based Munich Cancer Registry. Between 1998 and 2014, 1048 female patients with diagnosis of DCIS and treated at two Breast Care Centres were included in this observational study. The effectiveness of postoperative radiotherapy and variables predicting the use of radiotherapy were retrospectively analysed. RESULTS: After adjusting for age, tumour characteristics and therapies, Cox regression analysis for local recurrence-free survival identified RT as an independent predictor for improved local control (HR: 0.579; 95%CI: 0.384-0.872, p = 0.008). Ten-year cumulative incidence of in-breast recurrences was 20.0% following BCS, compared to 13.6% in patients receiving postoperative radiotherapy (p = 0.012). As an estimate for disease-specific survival, 10-year relative survival was 105.4% for patients receiving postoperative radiotherapy and 101.6% without radiotherapy. On multivariate analysis, postoperative radiotherapy was not associated with improved overall survival (HR 0.526; 95%CI: 0.263-1.052, p = 0.069). Over time, a significant increase of RT was registered: while 1998 only 42.9% of patients received postoperative radiotherapy, the proportion rose to 91.2% in 2014. Women aged < 50 years (OR: 2.559, 95%CI: 1.416-4.625, p < 0.001) or with negative hormone receptor status (OR: 2.625, 95%CI: 1.458-4.728, p = 0.001) or receiving endocrine therapy (OR: 1.762, 95%CI: 1.060-2.927, p = 0.029) were more likely to receive postoperative radiotherapy after BCS. CONCLUSIONS: In conclusion, this study provides insights regarding the adoption and treatment pattern of postoperative RT following BCS for DCIS in a large cohort reflecting "real-life" clinical practice in this setting. Postoperative RT was found to be associated with a reduced risk of ipsilateral recurrence and no survival benefit compared to observation alone.


Asunto(s)
Neoplasias de la Mama/radioterapia , Carcinoma Ductal de Mama/radioterapia , Carcinoma Intraductal no Infiltrante/radioterapia , Recurrencia Local de Neoplasia/prevención & control , Anciano , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/patología , Carcinoma Ductal de Mama/cirugía , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Intraductal no Infiltrante/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mastectomía Segmentaria , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
17.
Strahlenther Onkol ; 194(3): 196-205, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28916844

RESUMEN

PURPOSE: Modern breast cancer radiotherapy techniques, such as respiratory-gated radiotherapy in deep-inspiration breath-hold (DIBH) or volumetric-modulated arc radiotherapy (VMAT) have been shown to reduce the high dose exposure of the heart in left-sided breast cancer. The aim of the present study was to comparatively estimate the excess relative and absolute risks of radiation-induced secondary lung cancer and ischemic heart disease for different modern radiotherapy techniques. METHODS: Four different treatment plans were generated for ten computed tomography data sets of patients with left-sided breast cancer, using either three-dimensional conformal radiotherapy (3D-CRT) or VMAT, in free-breathing (FB) or DIBH. Dose-volume histograms were used for organ equivalent dose (OED) calculations using linear, linear-exponential, and plateau models for the lung. A linear model was applied to estimate the long-term risk of ischemic heart disease as motivated by epidemiologic data. Excess relative risk (ERR) and 10-year excess absolute risk (EAR) for radiation-induced secondary lung cancer and ischemic heart disease were estimated for different representative baseline risks. RESULTS: The DIBH maneuver resulted in a significant reduction of the ERR and estimated 10-year excess absolute risk for major coronary events compared to FB in 3D-CRT plans (p = 0.04). In VMAT plans, the mean predicted risk reduction through DIBH was less pronounced and not statistically significant (p = 0.44). The risk of radiation-induced secondary lung cancer was mainly influenced by the radiotherapy technique, with no beneficial effect through DIBH. VMAT plans correlated with an increase in 10-year EAR for radiation-induced lung cancer as compared to 3D-CRT plans (DIBH p = 0.007; FB p = 0.005, respectively). However, the EARs were affected more strongly by nonradiation-associated risk factors, such as smoking, as compared to the choice of treatment technique. CONCLUSION: The results indicate that 3D-CRT plans in DIBH pose the lowest risk for both major coronary events and secondary lung cancer.


Asunto(s)
Neoplasias de la Mama/radioterapia , Neoplasias Pulmonares/etiología , Isquemia Miocárdica/etiología , Neoplasias Inducidas por Radiación/etiología , Neoplasias Primarias Secundarias/etiología , Radioterapia Conformacional/efectos adversos , Radioterapia de Intensidad Modulada/efectos adversos , Anciano , Contencion de la Respiración , Femenino , Corazón/efectos de la radiación , Humanos , Persona de Mediana Edad , Traumatismos por Radiación/etiología , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Técnicas de Imagen Sincronizada Respiratorias/efectos adversos , Riesgo
18.
Strahlenther Onkol ; 194(3): 273-274, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29098303

RESUMEN

Correction to: Strahlenther Onkol 2017 https://doi.org/10.1007/s00066-017-1213-y Unfortunately, during copy editing, the titles of Fig. 2a and 2b were removed.The correct Fig. 2a and 2b are shown below. The original article has been corrected ….

19.
Strahlenther Onkol ; 193(4): 324-331, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28124093

RESUMEN

BACKGROUND: The optimal sequence of mastectomy with immediate breast reconstruction (IBR) and radiotherapy (RT) for the treatment of locally advanced breast cancer (LABC) is still under debate. Increased rates of postoperative complications are described following postmastectomy RT. Neoadjuvant RT aims to improve the aesthetic results and simplify the reconstructive pathway. PATIENTS: A total of 22 patients diagnosed with LABC and treated with neoadjuvant RT followed by mastectomy and IBR between 04/2012 and 03/2015 were retrospectively analyzed. RT consisted of external beam RT to the breast and the regional lymphatics, if indicated. Both implant-based and autologous tissue-transfer reconstruction techniques were used. RESULTS: At the time of RT, 10 patients had no prior surgery and 12 patients had previously undergone breast-conserving surgery (BCS) with positive resection margins without the possibility to perform a second BCS. Additional neoadjuvant chemotherapy was administered in 18 patients prior to RT. A complete pathological response was achieved in 55.0% of patients. The 2­year overall survival rate was 89.3%, the 2­year disease-free-survival 79.8% and the local-recurrence-free survival was 95.2%. The cosmetic result was excellent or good in 66% of the patients treated with upfront mastectomy and 37% of the patients who had previously undergone BCS. Among patients who received implant-based IBR, 4 patients developed serious wound-healing problems with implant loss. The most satisfactory results were achieved with autologous tissue reconstruction. CONCLUSION: A sequential neoadjuvant chemo-/radiotherapy to allow IBR following mastectomy in selected cases of LABC seems feasible and can be safely attempted. Careful patient selection, close monitoring, and continuous patient support is mandatory to ensure compliance in this treatment strategy.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Mamoplastia/métodos , Mastectomía/métodos , Radioterapia Conformacional/métodos , Adulto , Anciano , Neoplasias de la Mama/psicología , Terapia Combinada/métodos , Vías Clínicas/organización & administración , Femenino , Humanos , Mamoplastia/psicología , Mastectomía/psicología , Persona de Mediana Edad , Satisfacción del Paciente , Dosificación Radioterapéutica , Radioterapia Adyuvante/métodos , Radioterapia Adyuvante/psicología , Radioterapia Conformacional/psicología , Resultado del Tratamiento
20.
J Phys Condens Matter ; 28(39): 395001, 2016 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-27484794

RESUMEN

The formation energy of the interface between face-centered cubic (fcc) and hexagonal close packed (hcp) structures is a key parameter in determining the stacking fault energy (SFE) of fcc metals and alloys using thermodynamic calculations. It is often assumed that the contribution of the planar fault energy to the SFE has the same order of magnitude as the bulk part, and thus the lack of precise information about it can become the limiting factor in thermodynamic predictions. Here, we differentiate between the interfacial energy for the coherent fcc(1 1 1)/hcp(0 0 0 1) interface and the 'pseudo-interfacial energy' that enters the thermodynamic expression for the SFE. Using first-principles calculations, we determine the coherent and pseudo-interfacial energies for six elemental metals (Al, Ni, Cu, Ag, Pt, and Au) and three paramagnetic Fe-Cr-Ni alloys. Our results show that the two interfacial energies significantly differ from each other. We observe a strong chemistry dependence for both interfacial energies. The calculated pseudo-interfacial energies for the Fe-Cr-Ni steels agree well with the available literature data. We discuss the effects of strain on the description of planar faults via thermodynamic and ab initio approaches.

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