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Practical Radiation Oncology 2020Stereotactic body radiation therapy (SBRT) is increasingly used for nonspine bone metastases (NSBM); however, there are limited data informing treatment planning. We...
PURPOSE
Stereotactic body radiation therapy (SBRT) is increasingly used for nonspine bone metastases (NSBM); however, there are limited data informing treatment planning. We surveyed international experts to better understand worldwide practice patterns in delivering NSBM-SBRT.
METHODS AND MATERIALS
Nine international radiation oncologists were invited to participate based on demonstrated expertise with NSBM-SBRT. Experts were sent gross tumor volume contours and planning computed tomography and magnetic resonance images for 11 NSBM cases that covered a range of bony sites, including metastases to long bones (femur, humerus), pelvic bones (ilium, ischium, acetabulum, pubic symphysis), and thoracic bones (rib, sternum, scapula, clavicle). Experts were surveyed regarding treatment planning decisions and dose-fractionation selection. Descriptive analysis was conducted on the survey data.
RESULTS
All experts participated and completed the survey. Most (56%) routinely fused magnetic resonance imaging with planning computed tomography imaging for target delineation. Dose fractionation schedules included single-fraction (18-24 Gy/1), 2 fractions (24 Gy/2), 3 fractions (28-30 Gy/3), 5 fractions (30-50 Gy/5), and 10 fractions (42-50 Gy/10). Although doses varied considerably, all had a biological equivalent dose of ≤100 Gy. Five-fraction schedules were most common, specifically 35 Gy/5, with 56% opting for this dose-fractionation in at least 1 case. Other dose-fractionation schedules used by at least 3 experts were 20 Gy/1, 30 Gy/3, and 30 Gy/5. Three experts prescribed 2 dose volumes using a simultaneous integrated boost. The 2 dose volumes were either the gross tumor volume and clinical target volume (CTV) or a smaller CTV (CTV1) encompassed within a larger CTV (CTV2) (eg, 30 Gy/3 to gross tumor volume or CTV1 and 15-24 Gy/3 to CTV or CTV2). Dose de-escalation was recommended by all experts in the setting of previous SBRT and by most in the context of previous convevoltherapy or in weight-bearing bones, especially if moderate-to-severe cortical erosion was present.
CONCLUSIONS
Significant heterogeneity exists worldwide in radiation technique and dose-fractionation for NSBM-SBRT, which supports the need for consensus guidelines to inform practice and trial design. Nonetheless, these data demonstrate expert agreement on selecting dose schedules with a biologically effective dose ≤100 Gy, reasons for dose de-escalation, and in determining acceptable dose schedules based on bony site.
Topics: Bone Neoplasms; Dose Fractionation, Radiation; Humans; Magnetic Resonance Imaging; Radiosurgery; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted
PubMed: 32171852
DOI: 10.1016/j.prro.2020.02.011 -
The Lancet. Oncology Jan 2022High-quality randomised clinical trials testing moderately fractionated breast radiotherapy have clearly shown that local control and survival is at least as effective... (Review)
Review
European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus recommendations on patient selection and dose and fractionation for external beam radiotherapy in early breast cancer.
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 five-fraction 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.
Topics: Advisory Committees; Breast Neoplasms; COVID-19; Consensus; Dose Fractionation, Radiation; Europe; Evidence-Based Medicine; Female; Humans; Patient Selection; Radiation Dose Hypofractionation; Radiation Oncology
PubMed: 34973228
DOI: 10.1016/S1470-2045(21)00539-8 -
Journal For Immunotherapy of Cancer Apr 2021Recent evidence indicates that ionizing radiation can enhance immune responses to tumors. Advances in radiation delivery techniques allow hypofractionated delivery of... (Review)
Review
Recent evidence indicates that ionizing radiation can enhance immune responses to tumors. Advances in radiation delivery techniques allow hypofractionated delivery of conformal radiotherapy. Hypofractionation or other modifications of standard fractionation may improve radiation's ability to promote immune responses to tumors. Other novel delivery options may also affect immune responses, including T-cell activation and tumor-antigen presentation changes. However, there is limited understanding of the immunological impact of hypofractionated and unique multifractionated radiotherapy regimens, as these observations are relatively recent. Hence, these differences in radiotherapy fractionation result in distinct immune-modulatory effects. Radiation oncologists and immunologists convened a virtual consensus discussion to identify current deficiencies, challenges, pitfalls and critical gaps when combining radiotherapy with immunotherapy and making recommendations to the field and advise National Cancer Institute on new directions and initiatives that will help further development of these two fields.This commentary aims to raise the awareness of this complexity so that the need to study radiation dose, fractionation, type and volume is understood and valued by the immuno-oncology research community. Divergence of approaches and findings between preclinical studies and clinical trials highlights the need for evaluating the design of future clinical studies with particular emphasis on radiation dose and fractionation, immune biomarkers and selecting appropriate end points for combination radiation/immune modulator trials, recognizing that direct effect on the tumor and potential abscopal effect may well be different. Similarly, preclinical studies should be designed as much as possible to model the intended clinical setting. This article describes a conceptual framework for testing different radiation therapy regimens as separate models of how radiation itself functions as an immunomodulatory 'drug' to provide alternatives to the widely adopted 'one-size-fits-all' strategy of frequently used 8 Gy×3 regimens immunomodulation.
Topics: Animals; Clinical Decision-Making; Combined Modality Therapy; Dose Fractionation, Radiation; Humans; Immunotherapy; Neoplasms; Patient Safety; Radiation Dosage; Risk Assessment; Risk Factors; Treatment Outcome; Tumor Microenvironment
PubMed: 33827904
DOI: 10.1136/jitc-2020-002038 -
International Journal of Radiation... Sep 2021The purpose of this critical review is to summarize the literature specific to single-fraction stereotactic radiosurgery (SRS) and multiple-fraction stereotactic... (Review)
Review
Stereotactic Radiosurgery for Postoperative Metastatic Surgical Cavities: A Critical Review and International Stereotactic Radiosurgery Society (ISRS) Practice Guidelines.
PURPOSE
The purpose of this critical review is to summarize the literature specific to single-fraction stereotactic radiosurgery (SRS) and multiple-fraction stereotactic radiation therapy (SRT) for postoperative brain metastases resection cavities and to present practice recommendations on behalf of the ISRS.
METHODS AND MATERIALS
The Medline and Embase databases were used to apply the Preferred Reporting Items for Systematic Reviews and Meta-Analyses approach to search for manuscripts reporting SRS/SRT outcomes for postoperative brain metastases tumor bed resection cavities with a search end date of July 20, 2018. Prospective studies, consensus guidelines, and retrospective series that included exclusively postoperative brain metastases and had at minimum 100 patients were considered eligible.
RESULTS
The Embase search revealed 157 manuscripts, of which 77 were selected for full-text screening. PubMed yielded 55 manuscripts, of which 23 were selected for full text screening. We deemed 8 retrospective series, 1 phase 2 prospective study, 3 randomized controlled trials, and 1 consensus contouring paper appropriate for inclusion. The data suggest that SRS/SRT to surgical cavities with prescription doses of 30 to 50 Gy equivalent effective dose (EQD) 2, 50 to 70 Gy EQD2, and 70 to 90 EQD2 are associated with rates of local control ranging from 60.5% to 91% (median, 80.5%). Randomized data suggest improved local control with single-fraction SRS compared with observation and improved cognitive outcomes compared with whole-brain radiation therapy (WBRT). The toxicity of SRS/SRT in the postoperative setting was limited and is reviewed herein.
CONCLUSIONS
Although randomized data raise concern for poorer local control after resection cavity SRS than WBRT, these findings may be driven by factors such as conservative prescription doses used in the SRS arm. Retrospective studies suggest high rates of local control after single-fraction SRS and hypofractionated SRT for postoperative brain metastases. With a superior neurocognitive profile and no survival disadvantage to withholding WBRT, the ISRS recommends SRS as first-line treatment for eligible postoperative patients. Emerging data suggest that fractionated SRT may provide superior local control compared with single-fraction SRS, in particular, for large tumor cavity volumes/diameters and potentially for patients with a preoperative diameter greater than 2.5 cm.
Topics: Brain Neoplasms; Cognition; Cranial Irradiation; Dose Fractionation, Radiation; Humans; Meningeal Neoplasms; Practice Guidelines as Topic; Radiosurgery
PubMed: 33891979
DOI: 10.1016/j.ijrobp.2021.04.016 -
Clinical Lung Cancer Jul 2018Lung stereotactic body radiotherapy (SBRT) is considered a standard curative treatment for medically inoperable early stage non-small-cell lung cancer (NSCLC). Patients...
BACKGROUND
Lung stereotactic body radiotherapy (SBRT) is considered a standard curative treatment for medically inoperable early stage non-small-cell lung cancer (NSCLC). Patients with ultracentral tumors (signifying tumors whose planning target volume touches or overlaps the central bronchial tree, esophagus, or pulmonary artery) may be at higher risk of serious toxicities such as bronchial stricture and collapse, esophageal strictures, tracheal-esophageal fistula, and hemorrhage. The primary objective of the study is to determine the maximum tolerated dose of radiotherapy for ultracentral NSCLC.
METHODS
This multicenter phase 1 dose-escalation study will use a time-to-event continual reassessment method (TITE-CRM). Accrual will start at level 1 (60 Gy in 8 fractions delivered daily). The model will use all available information from previously accrued patients to assign the highest dose with a predicted risk of grade 3-5 toxicity of 30% or less. All patients with newly diagnosed stage T1-3 N0M0 NSCLC (International Union Against Cancer, 8th edition) with tumor size ≤ 6 cm and meeting the criteria for ultracentral location (ie, tumors whose planning target volume touches or overlaps the central bronchial tree, esophagus, pulmonary vein, or pulmonary artery) will be eligible for this study.
DISCUSSION
It is important to identify a safe dose-fractionation regimen for treating ultracentral tumors with SBRT. In addition, the data from this study may be informative in guiding future studies on the use of SBRT in treating malignancies within the mediastinum-for example, for salvage treatment of mediastinal lymph nodes for recurrent NSCLC or mediastinal oligometastases.
Topics: Carcinoma, Non-Small-Cell Lung; Dose Fractionation, Radiation; Humans; Lung Neoplasms; Maximum Tolerated Dose; Radiosurgery; Radiotherapy Dosage; Research Design
PubMed: 29759332
DOI: 10.1016/j.cllc.2018.04.001 -
Lung Cancer (Amsterdam, Netherlands) Aug 2023Stereotactic body radiotherapy (SBRT) is an effective and safe modality for early-stage lung cancer and lung metastases. However, tumors in an ultra-central location... (Meta-Analysis)
Meta-Analysis
Stereotactic body radiotherapy for Ultra-Central lung Tumors: A systematic review and Meta-Analysis and International Stereotactic Radiosurgery Society practice guidelines.
BACKGROUND
Stereotactic body radiotherapy (SBRT) is an effective and safe modality for early-stage lung cancer and lung metastases. However, tumors in an ultra-central location pose unique safety considerations. We performed a systematic review and meta-analysis to summarize the current safety and efficacy data and provide practice recommendations on behalf of the International Stereotactic Radiosurgery Society (ISRS).
METHODS
We performed a systematic review using PubMed and EMBASE databases of patients with ultra-central lung tumors treated with SBRT. Studies reporting local control (LC) and/or toxicity were included. Studies with <5 treated lesions, non-English language, re-irradiation, nodal tumors, or mixed outcomes in which ultra-central tumors could not be discerned were excluded. Random-effects meta-analysis was performed for studies reporting relevant endpoints. Meta-regression was conducted to determine the effect of various covariates on the primary outcomes.
RESULTS
602 unique studies were identified of which 27 (one prospective observational, the remainder retrospective) were included, representing 1183 treated targets. All studies defined ultra-central as the planning target volume (PTV) overlapping the proximal bronchial tree (PBT). The most common dose fractionations were 50 Gy/5, 60 Gy/8, and 60 Gy/12 fractions. The pooled 1- and 2-year LC estimates were 92 % and 89 %, respectively. Meta-regression identified biological effective dose (BED10) as a significant predictor of 1-year LC. A total of 109 grade 3-4 toxicity events, with a pooled incidence of 6 %, were reported, most commonly pneumonitis. There were 73 treatment related deaths, with a pooled incidence of 4 %, with the most common being hemoptysis. Anticoagulation, interstitial lung disease, endobronchial tumor, and concomitant targeted therapies were observed risk factors for fatal toxicity events.
CONCLUSION
SBRT for ultra-central lung tumors results in acceptable rates of local control, albeit with risks of severe toxicity. Caution should be taken for appropriate patient selection, consideration of concomitant therapies, and radiotherapy plan design.
Topics: Humans; Lung Neoplasms; Radiosurgery; Retrospective Studies; Lung; Dose Fractionation, Radiation; Observational Studies as Topic
PubMed: 37393758
DOI: 10.1016/j.lungcan.2023.107281 -
Progress in Brain Research 2022New understandings of the biology of radiosurgery are considered. Differences from the radiobiology of fractionated radiotherapy are outlined. It is noted DNA damage...
New understandings of the biology of radiosurgery are considered. Differences from the radiobiology of fractionated radiotherapy are outlined. It is noted DNA damage alone is insufficient to account for the tissue changes which occur. Changes in blood vessels and immunological mechanisms are also involved. Tissue repair is more rapid than previously thought so that dose rate (the rate of delivery of radiation to the tissues) has been seen to be more important. The value of fractionation is examined. The effect of radiosurgery on normal brain (so called functional radiosurgery) is considered. The desired effects may be achieved by a focal stable destruction of brain from a high radiation dose. They may also be achieved using a lower dose which acts through the mechanism known as radiosurgical neuromodulation.
Topics: Brain; Dose Fractionation, Radiation; Humans; Radiobiology; Radiosurgery
PubMed: 35074083
DOI: 10.1016/bs.pbr.2021.10.024 -
Journal of Thoracic Oncology : Official... Jul 2021Stereotactic body radiation therapy of thoracic tumors close to the central airways implies risk of severe toxicity. We report a prospective multicenter phase 2 trial...
INTRODUCTION
Stereotactic body radiation therapy of thoracic tumors close to the central airways implies risk of severe toxicity. We report a prospective multicenter phase 2 trial for tumors located less than or equal to 1 cm from the proximal bronchial tree with primary end point of local control and secondary end point of toxicity.
METHODS
Stereotactic body radiation therapy with 7 Gy × 8 was prescribed to the 67% isodose encompassing the planning target volume. The patients were stratified to group A (tumors ≤ 1 cm from the main bronchi and trachea) or group B (all other tumors). Risk factors for treatment-related death were tested in univariate analysis, and a logistic regression model was developed for fatal bronchopulmonary bleeding versus dose to the main bronchi and trachea.
RESULTS
A total of 65 patients (group A/group B, n = 39/26) were evaluated. The median distance between the tumor and the proximal bronchial tree was 0 mm (0-10 mm). The 2-year local control was 83%. Grade 3 to 5 toxicity was noted in 22 patients, including 10 cases of treatment-related death (bronchopulmonary hemorrhage, n = 8; pneumonitis, n = 1; fistula, n = 1). Dose to the combined structure main bronchi and trachea and tumor distance to the main bronchi were important risk factors. Dose modeling revealed minimum dose to the "hottest" 0.2 cc to the structure main bronchi and trachea as the strongest predictor for lethal bronchopulmonary hemorrhage.
CONCLUSIONS
On the basis of the presented data, 7 Gy × 8, prescribed to the planning target volume-encompassing isodose, should not be used for tumors located within 1 cm from the main bronchi and trachea. Group B-type tumors may be considered for the treatment on the basis of an individual risk-benefit assessment and a maximum dose to the main bronchi and trachea in the order of 70 to 80 Gy (equivalent dose in 2 Gy fractions).
Topics: Dose Fractionation, Radiation; Humans; Lung; Lung Neoplasms; Prospective Studies; Radiosurgery; Radiotherapy Dosage
PubMed: 33823286
DOI: 10.1016/j.jtho.2021.03.019 -
Cancer Radiotherapie : Journal de La... 2022We present the update of the recommendations of the French society of oncological radiotherapy on radiotherapy for hypopharynx. Intensity-modulated radiotherapy is the...
We present the update of the recommendations of the French society of oncological radiotherapy on radiotherapy for hypopharynx. Intensity-modulated radiotherapy is the gold standard treatment for hypopharynx cancers. Early T1 and T2 tumors could be treated by exclusive radiotherapy or surgery followed by postoperative radiotherapy in case of high recurrence risk. For locally advanced tumours requiring total pharyngolaryngectomy (T2 or T3) or with significant lymph nodes involvement, induction chemotherapy followed by exclusive radiotherapy or concurrent chemoradiotherapy were possible. For T4 tumour, surgery must be proposed. The treatment of lymph nodes is based on initial primary tumour treatment. In non-surgical procedure, for 35 fractions, curative dose is 70Gy (2Gy per fraction) and prophylactic dose are 50 to 56Gy (2Gy per fraction in case of sequential radiotherapy or 1.6Gy in case of integrated simultaneous boost) radiotherapy; for 33 fractions, curative dose is 69.96Gy (2.12Gy per fraction) and prophylactic dose is 52.8Gy (1.6Gy per fraction in integrated simultaneous boost radiotherapy or 54Gy in 1.64Gy per fraction); for 30 fractions, curative dose is 66Gy (2.2Gy per fraction) and prophylactic dose is 54Gy (1.8Gy per fraction in integrated simultaneous boost radiotherapy). Doses over 2Gy per fraction could be done when chemotherapy is not used regarding potential larynx toxicity. Postoperatively, radiotherapy is used in locally advanced cancer with dose levels based on pathologic criteria, 60 to 66Gy for R1 resection and 54 to 60Gy for complete resection in bed tumour; 50 to 66Gy in lymph nodes areas regarding extracapsular spread. Volume delineation were based on guidelines cited in this article.
Topics: Chemoradiotherapy; Dose Fractionation, Radiation; France; Humans; Hypopharyngeal Neoplasms; Induction Chemotherapy; Laryngectomy; Lymphatic Irradiation; Pharyngectomy; Radiation Oncology; Radiotherapy, Intensity-Modulated
PubMed: 34953703
DOI: 10.1016/j.canrad.2021.10.006 -
Practical Radiation Oncology 2016To present evidence-based guidelines for radiation therapy in treating glioblastoma not arising from the brainstem.
PURPOSE
To present evidence-based guidelines for radiation therapy in treating glioblastoma not arising from the brainstem.
METHODS AND MATERIALS
The American Society for Radiation Oncology (ASTRO) convened the Glioblastoma Guideline Panel to perform a systematic literature review investigating the following: (1) Is radiation therapy indicated after biopsy/resection of glioblastoma and how does systemic therapy modify its effects? (2) What is the optimal dose-fractionation schedule for external beam radiation therapy after biopsy/resection of glioblastoma and how might treatment vary based on pretreatment characteristics such as age or performance status? (3) What are ideal target volumes for curative-intent external beam radiation therapy of glioblastoma? (4) What is the role of reirradiation among glioblastoma patients whose disease recurs following completion of standard first-line therapy? Guideline recommendations were created using predefined consensus-building methodology supported by ASTRO-approved tools for grading evidence quality and recommendation strength.
RESULTS
Following biopsy or resection, glioblastoma patients with reasonable performance status up to 70 years of age should receive conventionally fractionated radiation therapy (eg, 60 Gy in 2-Gy fractions) with concurrent and adjuvant temozolomide. Routine addition of bevacizumab to this regimen is not recommended. Elderly patients (≥70 years of age) with reasonable performance status should receive hypofractionated radiation therapy (eg, 40 Gy in 2.66-Gy fractions); preliminary evidence may support adding concurrent and adjuvant temozolomide to this regimen. Partial brain irradiation is the standard paradigm for radiation delivery. A variety of acceptable strategies exist for target volume definition, generally involving 2 phases (primary and boost volumes) or 1 phase (single volume). For recurrent glioblastoma, focal reirradiation can be considered in younger patients with good performance status.
CONCLUSIONS
Radiation therapy occupies an integral role in treating glioblastoma. Whether and how radiation therapy should be applied depends on characteristics specific to tumor and patient, including age and performance status.
Topics: Brain Neoplasms; Dose Fractionation, Radiation; Glioblastoma; Guidelines as Topic; Humans; Male; Prospective Studies; United States
PubMed: 27211230
DOI: 10.1016/j.prro.2016.03.007