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Current Oncology (Toronto, Ont.) Apr 2020The Canadian Cancer Society estimated that 220,400 new cases of cancer would be diagnosed in 2019. Of the affected patients, more than 60% will survive for 5 years or... (Review)
Review
The Canadian Cancer Society estimated that 220,400 new cases of cancer would be diagnosed in 2019. Of the affected patients, more than 60% will survive for 5 years or longer after their cancer diagnosis. Furthermore, nearly 40% will receive at least 1 course of radiotherapy (rt). Radiotherapy is used with both curative and palliative intent: to treat early-stage or locally advanced tumours (curative) and for symptom management in advanced disease (palliative). It can be delivered systemically (external-beam rt) or internally (brachytherapy). Although technique improvements have drastically reduced the occurrence of rt-related toxicity, most patients still experience burdensome rt side effects (seffs). Radiotherapy seffs are local or locoregional, and manifest in tissues or organs that were irradiated. Side effects manifesting within weeks after rt completion are termed "early seffs," and those occurring months or years after treatment are termed "late seffs." In addition to radiation oncologists, general practitioners in oncology and primary care providers are involved in survivorship care and management of rt seffs. Here, we present an overview of common seffs and their respective management: anxiety, depression, fatigue, and effects related to the head-and-neck, thoracic, and pelvic treatment sites.
Topics: Female; Humans; Male; Neoplasms; Radiotherapy; Radiotherapy Dosage; Survivorship
PubMed: 32489253
DOI: 10.3747/co.27.6233 -
The British Journal of Radiology Mar 2019Extraordinary normal tissue response to highly spatially fractionated X-ray beams has been explored for over 25 years. More recently, alternative radiation sources have... (Review)
Review
Extraordinary normal tissue response to highly spatially fractionated X-ray beams has been explored for over 25 years. More recently, alternative radiation sources have been developed and utilized with the aim to evoke comparable effects. These include protons, which lend themselves well for this endeavour due to their physical depth dose characteristics as well as corresponding variable biological effectiveness. This paper addresses the motivation for using protons to generate spatially fractionated beams and reviews the technological implementations and experimental results to date. This includes simulation and feasibility studies, collimation and beam characteristics, dosimetry and biological considerations as well as the results of in vivo and in vitro studies. Experimental results are emerging indicating an extraordinary normal tissue sparing effect analogous to what has been observed for synchrotron generated X-ray microbeams. The potential for translational research and feasibility of spatially modulated proton beams in clinical settings is discussed.
Topics: Animals; Dose Fractionation, Radiation; Humans; Proton Therapy; Radiometry; Radiotherapy Dosage
PubMed: 30359081
DOI: 10.1259/bjr.20180466 -
Ugeskrift For Laeger Oct 2019This review summarises the potential usage of proton therapy in Denmark. About one third of Danes are diagnosed with cancer, and half of these need radiotherapy in the... (Review)
Review
This review summarises the potential usage of proton therapy in Denmark. About one third of Danes are diagnosed with cancer, and half of these need radiotherapy in the course of treatment. Radiation dose cannot be adequately increased without giving rise to unacceptable, high risk of toxicity, but proton therapy is encouraging due to a unique depth dose distribution. In some cases, the benefit of proton therapy is obvious, but in most cases the gain is less obvious, and patients should only receive treatment within clinical trials. Clinical studies on proton therapy with focus on reduction of radiation-induced side effects and improvement of quality of life should be conducted.
Topics: Denmark; Humans; Proton Therapy; Quality of Life; Radiation Injuries; Radiotherapy Dosage
PubMed: 31610837
DOI: No ID Found -
The British Journal of Radiology Sep 2014Dosimetric audit is required for the improvement of patient safety in radiotherapy and to aid optimization of treatment. The reassurance that treatment is being... (Review)
Review
Dosimetric audit is required for the improvement of patient safety in radiotherapy and to aid optimization of treatment. The reassurance that treatment is being delivered in line with accepted standards, that delivered doses are as prescribed and that quality improvement is enabled is as essential for brachytherapy as it is for the more commonly audited external beam radiotherapy. Dose measurement in brachytherapy is challenging owing to steep dose gradients and small scales, especially in the context of an audit. Several different approaches have been taken for audit measurement to date: thimble and well-type ionization chambers, thermoluminescent detectors, optically stimulated luminescence detectors, radiochromic film and alanine. In this work, we review all of the dosimetric brachytherapy audits that have been conducted in recent years, look at current audits in progress and propose required directions for brachytherapy dosimetric audit in the future. The concern over accurate source strength measurement may be essentially resolved with modern equipment and calibration methods, but brachytherapy is a rapidly developing field and dosimetric audit must keep pace.
Topics: Brachytherapy; Calibration; Humans; Medical Audit; Radiometry; Radiotherapy Dosage; Thermoluminescent Dosimetry
PubMed: 24807068
DOI: 10.1259/bjr.20140105 -
Physics in Medicine and Biology Nov 2021Radiation therapy treatments are typically planned based on a single image set, assuming that the patient's anatomy and its position relative to the delivery system... (Review)
Review
Radiation therapy treatments are typically planned based on a single image set, assuming that the patient's anatomy and its position relative to the delivery system remains constant during the course of treatment. Similarly, the prescription dose assumes constant biological dose-response over the treatment course. However, variations can and do occur on multiple time scales. For treatment sites with significant intra-fractional motion, geometric changes happen over seconds or minutes, while biological considerations change over days or weeks. At an intermediate timescale, geometric changes occur between daily treatment fractions. Adaptive radiation therapy is applied to consider changes in patient anatomy during the course of fractionated treatment delivery. While traditionally adaptation has been done off-line with replanning based on new CT images, online treatment adaptation based on on-board imaging has gained momentum in recent years due to advanced imaging techniques combined with treatment delivery systems. Adaptation is particularly important in proton therapy where small changes in patient anatomy can lead to significant dose perturbations due to the dose conformality and finite range of proton beams. This review summarizes the current state-of-the-art of on-line adaptive proton therapy and identifies areas requiring further research.
Topics: Humans; Proton Therapy; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted
PubMed: 34710858
DOI: 10.1088/1361-6560/ac344f -
Annals of Palliative Medicine Mar 2020Whole-breast radiotherapy after breast-conserving surgery (BCS) can improve patient survival while reducing local tumor recurrence. Although standard breast radiotherapy... (Review)
Review
Whole-breast radiotherapy after breast-conserving surgery (BCS) can improve patient survival while reducing local tumor recurrence. Although standard breast radiotherapy can achieve good tumor control and cosmetic effects with low toxicity, the 5- to 7-week treatment time is relatively long for patients and can result in wasted medical resources. Therefore, there is a growing trend toward hypofractionated radiotherapy (HFRT), which accelerates partial-breast irradiation. Both short-course radiotherapy and conventional fractionated radiotherapy are safe and effective treatment modes, with similar survival and local tumor control effects as those of conventional radiotherapy (CRT), and adverse reactions can be tolerated. Compared with conventional fractionated radiotherapy, short-course radiotherapy saves medical resources and has a shorter total treatment time, reduced treatment costs, and an improved quality of life for patients.
Topics: Breast Neoplasms; Female; Humans; Mastectomy, Segmental; Neoplasm Recurrence, Local; Neoplasm Staging; Radiation Dose Hypofractionation; Radiotherapy Dosage; Radiotherapy, Adjuvant; Treatment Outcome
PubMed: 32233620
DOI: 10.21037/apm.2020.02.18 -
International Journal of Hyperthermia :... 2016Planning of combined radiotherapy and hyperthermia treatments should be performed taking the synergistic action between the two modalities into account. This work... (Review)
Review
Planning of combined radiotherapy and hyperthermia treatments should be performed taking the synergistic action between the two modalities into account. This work evaluates the available experimental data on cytotoxicity of combined radiotherapy and hyperthermia treatment and the requirements for integration of hyperthermia and radiotherapy treatment planning into a single planning platform. The underlying synergistic mechanisms of hyperthermia include inhibiting DNA repair, selective killing of radioresistant hypoxic tumour tissue and increased radiosensitivity by enhanced tissue perfusion. Each of these mechanisms displays different dose-effect relations, different optimal time intervals and different optimal sequences between radiotherapy and hyperthermia. Radiosensitisation can be modelled using the linear-quadratic (LQ) model to account for DNA repair inhibition by hyperthermia. In a recent study, an LQ model-based thermoradiotherapy planning (TRTP) system was used to demonstrate that dose escalation by hyperthermia is equivalent to ∼10 Gy for prostate cancer patients treated with radiotherapy. The first step for more reliable TRTP is further expansion of the data set of LQ parameters for normally oxygenated normal and tumour tissue valid over the temperature range used clinically and for the relevant time intervals between radiotherapy and hyperthermia. The next step is to model the effect of hyperthermia in hypoxic tumour cells including the physiological response to hyperthermia and the resulting reoxygenation. Thermoradiotherapy planning is feasible and a necessity for an optimal clinical application of hyperthermia combined with radiotherapy in individual patients.
Topics: Animals; Combined Modality Therapy; Humans; Hyperthermia, Induced; Models, Biological; Neoplasms; Radiation Tolerance; Radiotherapy Dosage
PubMed: 26670625
DOI: 10.3109/02656736.2015.1110757 -
Radiation Oncology (London, England) Feb 2017Intraoperative irradiation was implemented 4 decades ago, pioneering the efforts to improve precision in local cancer therapy by combining real-time surgical...
Intraoperative irradiation was implemented 4 decades ago, pioneering the efforts to improve precision in local cancer therapy by combining real-time surgical exploration/resection with high single dose radiotherapy (Gunderson et al., Intraoperative irradiation: techniques and results, 2011). Clinical and technical developments have led to very precise radiation dose deposit. The ability to deliver a very precise dose of radiation is an essential element of contemporary multidisciplinary individualized oncology.This issue of Radiation Oncology contains a collection of expert review articles and updates with relevant data regarding intraoperative radiotherapy. Technology, physics, biology of single dose and clinical results in a variety of cancer sites and histologies are described and analyzed. The state of the art for advanced cancer care through medical innovation opens a significant opportunity for individualize cancer management across a broad spectrum of clinical practice. The advantage for tailoring diagnostic and treatment decisions in an individualized fashion will translate into precise medical treatment.
Topics: Humans; Intraoperative Period; Neoplasms; Precision Medicine; Radiotherapy; Radiotherapy Dosage
PubMed: 28148287
DOI: 10.1186/s13014-017-0764-5 -
Journal of Thoracic Oncology : Official... Oct 2020
Topics: Carcinoma, Non-Small-Cell Lung; Humans; Lung Neoplasms; Radiotherapy; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted
PubMed: 32981597
DOI: 10.1016/j.jtho.2020.07.004 -
Clinical Oncology (Royal College of... Feb 2022Artificial intelligence, and in particular deep learning using convolutional neural networks, has been used extensively for image classification and segmentation,... (Review)
Review
Artificial intelligence, and in particular deep learning using convolutional neural networks, has been used extensively for image classification and segmentation, including on medical images for diagnosis and prognosis prediction. Use in radiotherapy prognostic modelling is still limited, however, especially as applied to toxicity and tumour response prediction from radiation dose distributions. We review and summarise studies that applied deep learning to radiotherapy dose data, in particular studies that utilised full three-dimensional dose distributions. Ten papers have reported on deep learning models for outcome prediction utilising spatial dose information, whereas four studies used reduced dimensionality (dose volume histogram) information for prediction. Many of these studies suffer from the same issues that plagued early normal tissue complication probability modelling, including small, single-institutional patient cohorts, lack of external validation, poor data and model reporting, use of late toxicity data without taking time-to-event into account, and nearly exclusive focus on clinician-reported complications. They demonstrate, however, how radiation dose, imaging and clinical data may be technically integrated in convolutional neural networks-based models; and some studies explore how deep learning may help better understand spatial variation in radiosensitivity. In general, there are a number of issues specific to the intersection of radiotherapy outcome modelling and deep learning, for example translation of model developments into treatment plan optimisation, which will require further combined effort from the radiation oncology and artificial intelligence communities.
Topics: Artificial Intelligence; Deep Learning; Humans; Prognosis; Radiation Oncology; Radiotherapy Dosage
PubMed: 34924256
DOI: 10.1016/j.clon.2021.12.002