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1.
Radiotherapy and Oncology ; 170:S1298-S1300, 2022.
Article in English | EMBASE | ID: covidwho-1967483

ABSTRACT

Purpose or Objective Early assessment of neutron contamination in IMRT applications was based on delivery techniques [1,2]. Recently these delivery techniques have been optimized and made more efficient with respect to the number of MU required for a certain dose. In fact, the number of MU for many IMRT or VMAT treatments required for a certain fraction dose are now comparable to those required for 3D-conformal techniques. Furthermore, with the Covid-19 pandemic, a new hypofractionated breast treatment protocol was introduced in our department, based on the “Fast Forward” protocol [3,5]. The implementation of higher daily doses demands for stricter constraints. This study was initiated in order to determine a strategy in minimising the out-of-field dose in clinical practice taking into account the risks and benefits related to different treatment techniques and photon energies. Materials and Methods To simulate realistic clinical conditions, an anthropomorphic phantom was used with a right breast prosthesis. The phantom was scanned and appropriate structures (body, breast, lung and PTV) were delineated. Plans were created using Field in Field (FiF), IMRT and VMAT techniques with different energies. The mean dose of the PTV was normalised to the prescribed fraction dose (5.2Gy) in all treatment plans. Surface scanning was used to position the phantom for treatment. Different detectors types were used for measurements (see Table 1). The measurements were performed at 3 positions: one in the lung and two on the surface at 10 cm and 20 cm respectively from isocentre. Results Figures 1 and 2 illustrate the out-of-field dose measurements associated with a specific configuration of delivery technique and beam energy. Application of 15MV, for all delivery techniques combined, produced more neutrons compared to the other energies used in this study, the neutron contribution to the total contamination was up to 13% for 15 MV at 20 cm from isocentre. FiF neutron contribution were comparable to IMRT even if it required the least MU. In terms of photon scatter contribution, VMAT showed the highest doses. The neutron contamination for 10 MV and 10 MV FFF was similar. Considering a treatment fraction of 5.2 Gy delivered in 15MV IMRT mode, a neutron contamination of 5mGy was observed, which can be considered comparable to a CBCT acquisition for patient positioning [4]. Conclusion As IMRT provides better dose homogeneity and OAR sparing it can be preferred over FiF considering comparable contributions in out-of-field dose contamination. For some complex cases, such as irradiating regional lymph nodes for a breast treatment, VMAT can be considered, as the small increase in out-of-field dose might be balanced against an optimal target coverage / OAR sparing. As expected, some neutron contribution can be observed for the higher energies, however, the low levels of it to the total contamination dose as observed in this study might warrant their use in favour of improved target coverage and skin sparing. Appendix (Figure Presented)(Table Presented)

2.
LANCET ONCOLOGY ; 23(1):E21-E31, 2022.
Article in English | Web of Science | ID: covidwho-1965435

ABSTRACT

High-quality randomised clinical trials testing moderately fractionated breast radiotherapy have clearly shown that local control and survival is at least as effective as with 2 Gy daily fractions with similar or reduced normal tissue toxicity. Fewer treatment visits are welcomed by patients and their families, and reduced fractions produce substantial savings for health-care systems. Implementation of hypofractionation, however, has moved at a slow pace. The oncology community have now reached an inflection point created by new evidence from the FAST-Forward fivefraction randomised trial and catalysed by the need for the global radiation oncology community to unite during the COVID-19 pandemic and rapidly rethink hypofractionation implementation. The aim of this paper is to support equity of access for all patients to receive evidence-based breast external beam radiotherapy and to facilitate the translation of new evidence into routine daily practice. The results from this European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus state that moderately hypofractionated radiotherapy can be offered to any patient for whole breast, chest wall (with or without reconstruction), and nodal volumes. Ultrafractionation (five fractions) can also be offered for non-nodal breast or chest wall (without reconstruction) radiotherapy either as standard of care or within a randomised trial or prospective cohort. The consensus is timely;not only is it a pragmatic framework for radiation oncologists, but it provides a measured proposal for the path forward to influence policy makers and empower patients to ensure equity of access to evidence-based radiotherapy.

3.
Ann Oncol ; 32(10): 1216-1235, 2021 10.
Article in English | MEDLINE | ID: covidwho-1303426

ABSTRACT

The 17th St Gallen International Breast Cancer Consensus Conference in 2021 was held virtually, owing to the global COVID-19 pandemic. More than 3300 participants took part in this important bi-annual critical review of the 'state of the art' in the multidisciplinary care of early-stage breast cancer. Seventy-four expert panelists (see Appendix 1) from all continents discussed and commented on the previously elaborated consensus questions, as well as many key questions on early breast cancer diagnosis and treatment asked by the audience. The theme of this year's conference was 'Customizing local and systemic therapies.' A well-organized program of pre-recorded symposia, live panel discussions and real-time panel voting results drew a worldwide audience of thousands, reflecting the far-reaching impact of breast cancer on every continent. The interactive technology platform allowed, for the first time, audience members to ask direct questions to panelists, and to weigh in with their own vote on several key panel questions. A hallmark of this meeting was to focus on customized recommendations for treatment of early-stage breast cancer. There is increasing recognition that the care of a breast cancer patient depends on highly individualized clinical features, including the stage at presentation, the biological subset of breast cancer, the genetic factors that may underlie breast cancer risk, the genomic signatures that inform treatment recommendations, the extent of response before surgery in patients who receive neoadjuvant therapy, and patient preferences. This customized approach to treatment requires integration of clinical care between patients and radiology, pathology, genetics, and surgical, medical and radiation oncology providers. It also requires a dynamic response from clinicians as they encounter accumulating clinical information at the time of diagnosis and then serially with each step in the treatment plan and follow-up, reflecting patient experiences and treatment response.


Subject(s)
Breast Neoplasms , COVID-19 , Breast Neoplasms/diagnosis , Breast Neoplasms/epidemiology , Breast Neoplasms/therapy , Female , Humans , Neoadjuvant Therapy , Pandemics , SARS-CoV-2
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