المؤلفون: Dona Lemus, Olga, Cao, Minsong, Cai, Bin, Cummings, Michael, Zheng, Dandan

المصدر: Cancers. 16(6)

مصطلحات موضوعية: CBCT, IGRT, MRgRT, PET, adaptive radiotherapy, adaptive replanning, personalized medicine, treatment adaptation

الوصف: Radiotherapy, a crucial technique in cancer therapy, has traditionally relied on the premise of largely unchanging patient anatomy during the treatment course and encompassing uncertainties by target margins. This review introduces adaptive radiotherapy (ART), a notable innovation that addresses anatomy changes and optimizes the therapeutic ratio. ART utilizes advanced imaging techniques such as CT, MRI, and PET to modify the treatment plan based on observed anatomical changes and even biological changes during the course of treatment. The narrative review provides a comprehensive guide on ART for healthcare professionals and trainees in radiation oncology and anyone else interested in the topic. The incorporation of artificial intelligence in ART has played a crucial role in improving effectiveness, particularly in contour segmentation, treatment planning, and quality assurance. This has expedited the process to render online ART feasible, lowered the burden for radiation oncology practitioners, and enhanced the precision of dynamically personalized treatment. Current technical and clinical progress on ART is discussed in this review, highlighting the ongoing development of imaging technologies and AI and emphasizing their contribution to enhancing the applicability and effectiveness of ART.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/8n02549zTest

المؤلفون: Sreenija Yarlagadda, Yonatan Weiss, Michael David Chuong, Nema Bassiri, Alonso N. Gutierrez, Rupesh Kotecha, Minesh P. Mehta, Kathryn Elizabeth Mittauer

المصدر: Frontiers in Oncology, Vol 14 (2024)

مصطلحات موضوعية: MRgRT, dose-guided tracking, SBRT, ablative dose, GI OAR, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: In the current era of high-precision radiation therapy, real-time magnetic resonance (MR)-guided tracking of the tumor and organs at risk (OARs) is a novel approach that enables accurate and safe delivery of high-dose radiation. Organ tracking provides a general sense of the need for daily online adaptation but lacks precise information regarding exact dosimetry. To overcome this limitation, we developed the methodology for monitoring intrafraction motion with real-time MR-guided isodose line-based tracking of an OAR in combination with anatomic tumor-based tracking and reported the first case treated with this approach. An isolated para-aortic (PA) nodal recurrence from carcinosarcoma of the endometrium was treated with an ablative dose of 50 Gy in five fractions using MR-guided radiotherapy (MRgRT). This report demonstrates the feasibility, workflow, dosimetric constraints, and treatment paradigm for real-time isodose line-based OAR tracking and gating to enable an isotoxicity delivery approach. This innovative treatment strategy effectively tracked the intrafraction motion of both the target and OAR independently and enhanced the accuracy of structure localization in time and space with a more precise dosimetric evaluation.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fonc.2024.1357916/fullTest; https://doaj.org/toc/2234-943XTest

الوصول الحر: https://doaj.org/article/04f0345deb464253a099d9fa1e68b487Test

المؤلفون: He Wang, Jinzhong Yang, Anna Lee, Jack Phan, Tze Yee Lim, Clifton D. Fuller, Eun Young Han, Dong Joo Rhee, Travis Salzillo, Yao Zhao, Nitish Chopra, Mary Pham, Pam Castillo, Angela Sobremonte, Amy C. Moreno, Jay P. Reddy, David Rosenthal, Adam S. Garden, Xin Wang

المصدر: Clinical and Translational Radiation Oncology, Vol 46, Iss , Pp 100760- (2024)

مصطلحات موضوعية: MR-guided radiotherapy (MRgRT), Stereotactic body radiation therapy (SBRT), Head and neck, Medical physics. Medical radiology. Nuclear medicine, R895-920, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: Purpose: MR-guided radiotherapy (MRgRT) has the advantage of utilizing high soft tissue contrast imaging to track daily changes in target and critical organs throughout the entire radiation treatment course. Head and neck (HN) stereotactic body radiation therapy (SBRT) has been increasingly used to treat localized lesions within a shorter timeframe. The purpose of this study is to examine the dosimetric difference between the step-and-shot intensity modulated radiation therapy (IMRT) plans on Elekta Unity and our clinical volumetric modulated arc therapy (VMAT) plans on Varian TrueBeam for HN SBRT. Method: Fourteen patients treated on TrueBeam sTx with VMAT treatment plans were re-planned in the Monaco treatment planning system for Elekta Unity MR-Linac (MRL). The plan qualities, including target coverage, conformity, homogeneity, nearby critical organ doses, gradient index and low dose bath volume, were compared between VMAT and Monaco IMRT plans. Additionally, we evaluated the Unity adaptive plans of adapt-to-position (ATP) and adapt-to-shape (ATS) workflows using simulated setup errors for five patients and assessed the outcomes of our treated patients. Results: Monaco IMRT plans achieved comparable results to VMAT plans in terms of target coverage, uniformity and homogeneity, with slightly higher target maximum and mean doses. The critical organ doses in Monaco IMRT plans all met clinical goals; however, the mean doses and low dose bath volumes were higher than in VMAT plans. The adaptive plans demonstrated that the ATP workflow may result in degraded target coverage and OAR doses for HN SBRT, while the ATS workflow can maintain the plan quality. Conclusion: The use of Monaco treatment planning and online adaptation can achieve dosimetric results comparable to VMAT plans, with the additional benefits of real-time tracking of target volume and nearby critical structures. This offers the potential to treat aggressive and variable tumors in HN SBRT and improve local control and treatment toxicity.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2405630824000375Test; https://doaj.org/toc/2405-6308Test

الوصول الحر: https://doaj.org/article/5230891593424b32a1bff50d91edde57Test

المؤلفون: Martina Murr, Uffe Bernchou, Edyta Bubula-Rehm, Mark Ruschin, Parisa Sadeghi, Peter Voet, Jeff D Winter, Jinzhong Yang, Eyesha Younus, Cornel Zachiu, Yao Zhao, Hualiang Zhong, Daniela Thorwarth

المصدر: Physics and Imaging in Radiation Oncology, Vol 30, Iss , Pp 100588- (2024)

مصطلحات موضوعية: Deformable dose accumulation (DDA), Deformable image registration (DIR), Multi-institutional analysis, Online MR-guided radiotherapy (MRgRT), Medical physics. Medical radiology. Nuclear medicine, R895-920, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: Background and Purpose: Application of different deformable dose accumulation (DDA) solutions makes institutional comparisons after online-adaptive magnetic resonance-guided radiotherapy (OA-MRgRT) challenging. The aim of this multi-institutional study was to analyze accuracy and agreement of DDA-implementations in OA-MRgRT. Material and Methods: One gold standard (GS) case deformed with a biomechanical-model and five clinical cases consisting of prostate (2x), cervix, liver, and lymph node cancer, treated with OA-MRgRT, were analyzed. Six centers conducted DDA using institutional implementations. Deformable image registration (DIR) and DDA results were compared using the contour metrics Dice Similarity Coefficient (DSC), surface-DSC, Hausdorff-distance (HD95%), and accumulated dose-volume histograms (DVHs) analyzed via intraclass correlation coefficient (ICC) and clinical dosimetric criteria (CDC). Results: For the GS, median DDA errors ranged from 0.0 to 2.8 Gy across contours and implementations. DIR of clinical cases resulted in DSC > 0.8 for up to 81.3% of contours and a variability of surface-DSC values depending on the implementation. Maximum HD95%=73.3 mm was found for duodenum in the liver case. Although DVH ICC > 0.90 was found after DDA for all but two contours, relevant absolute CDC differences were observed in clinical cases: Prostate I/II showed maximum differences in bladder V28Gy (10.2/7.6%), while for cervix, liver, and lymph node the highest differences were found for rectum D2cm3 (2.8 Gy), duodenum Dmax (7.1 Gy), and rectum D0.5cm3 (4.6 Gy). Conclusion: Overall, high agreement was found between the different DIR and DDA implementations. Case- and algorithm-dependent differences were observed, leading to potentially clinically relevant results. Larger studies are needed to define future DDA-guidelines.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2405631624000587Test; https://doaj.org/toc/2405-6316Test

الوصول الحر: https://doaj.org/article/a7331327380a468a9b3d92909041d67cTest

المؤلفون: Wenheng Jiang, Xihua Shi, Xiang Zhang, Zhenjiang Li, Jinbo Yue

المصدر: Physics and Imaging in Radiation Oncology, Vol 30, Iss , Pp 100582- (2024)

مصطلحات موضوعية: MRgRT, MR-Linac, Upper abdominal tumor, MRI Contrast agent, Gadoterate meglumine, Medical physics. Medical radiology. Nuclear medicine, R895-920, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: This study investigates the use of contrast-enhanced magnetic resonance (MR) in MR-guided adaptive radiotherapy (MRgART) for upper abdominal tumors. Contrast-enhanced T1-weighted MR (cT1w MR) using half doses of gadoterate was used to guide daily adaptive radiotherapy for tumors poorly visualized without contrast. The use of gadoterate was found to be feasible and safe in 5-fraction MRgART and could improve the contrast-to-noise ratio of MR images. And the use of cT1w MR could reduce the interobserver variation of adaptive tumor delineation compared to plain T1w MR (4.41 vs. 6.58, p

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2405631624000526Test; https://doaj.org/toc/2405-6316Test

الوصول الحر: https://doaj.org/article/1d0ee7bed27046b4a879ce4d26ea2034Test

المؤلفون: Yu Gao, Stephanie Yoon, Ting Martin Ma, Yingli Yang, Ke Sheng, Daniel A. Low, Leslie Ballas, Michael L. Steinberg, Amar U Kishan, Minsong Cao

المصدر: Physics and Imaging in Radiation Oncology, Vol 30, Iss , Pp 100573- (2024)

مصطلحات موضوعية: Post-prostatectomy, Prostate cancer, MRI guided radiotherapy, MRgRT, Intrafractional variations, Medical physics. Medical radiology. Nuclear medicine, R895-920, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: Background and purpose: Magnetic Resonance Imaging (MRI)-guided Stereotactic body radiotherapy (SBRT) treatment to prostate bed after radical prostatectomy has garnered growing interests. The aim of this study is to evaluate intra-fractional anatomic and dose/volume metric variations for patients receiving this treatment. Materials and methods: Nineteen patients who received 30–34 Gy in 5 fractions on a 0.35T MR-Linac were included. Pre- and post-treatment MRIs were acquired for each fraction (total of 75 fractions). The Clinical Target Volume (CTV), bladder, rectum, and rectal wall were contoured on all images. Volumetric changes, Hausdorff distance, Mean Distance to Agreement (MDA), and Dice similarity coefficient (DSC) for each structure were calculated. Median value and Interquartile range (IQR) were recorded. Changes in target coverage and Organ at Risk (OAR) constraints were compared and evaluated using Wilcoxon rank sum tests at a significant level of 0.05. Results: Bladder had the largest volumetric changes, with a median volume increase of 48.9 % (IQR 28.9–76.8 %) and a median MDA of 5.1 mm (IQR 3.4–7.1 mm). Intra-fractional CTV volume remained stable with a median volume change of 1.2 % (0.0–4.8 %). DSC was 0.97 (IQR 0.94–0.99). For the dose/volume metrics, there were no statistically significant changes observed except for an increase in bladder hotspot and a decrease of bladder V32.5 Gy and mean dose. The CTV V95% changed from 99.9 % (IQR 98.8–100 %) to 99.6 % (IQR 93.9–100 %). Conclusion: Despite intra-fractional variations of OARs, CTV coverage remained stable during MRI-guided SBRT treatments for the prostate bed.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2405631624000435Test; https://doaj.org/toc/2405-6316Test

الوصول الحر: https://doaj.org/article/0148300d2dac423e93ae837d48d62081Test

المؤلفون: S.R. de Mol van Otterloo, J.M. Westerhoff, T. Leer, R.H.A. Rutgers, L.T.C. Meijers, L.A. Daamen, M.P.W. Intven, H.M. Verkooijen

المصدر: Technical Innovations & Patient Support in Radiation Oncology, Vol 29, Iss , Pp 100224- (2024)

مصطلحات موضوعية: MR-Linac, MRgRT, Patient reported outcomes, Patient reported experience measures (PREM), Medical physics. Medical radiology. Nuclear medicine, R895-920, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: Background and Purpose: Online adaptive MR-guided radiotherapy (MRgRT) is a relatively new form of radiotherapy treatment, delivered using a MR-Linac. It is unknown what patients expect from this treatment and whether these expectations are met. This study evaluates whether patients’ pre-treatment expectations of MRgRT are met and reports patients’ on-table experience on a 1.5 T MR-Linac. Materials and methods: All patients treated on the MR-Linac from November 2020 until April 2021, were eligible for inclusion. Patient expectation and experience were captured through questionnaires before, during, and three months after treatment. The on-table experience questionnaire included patient’ physical and psychological coping. Patient-expected side effects, participation in daily and social activity, disease outcome and, disease related symptoms were compared to post-treatment experience. Results: We included 113 patients who were primarily male (n = 100, 89 %), with a median age of 69 years (range 52–90). For on-table experience, ninety percent of patients (strongly) agreed to feeling calm during their treatment. Six and eight percent of patients found the treatment position or bed uncomfortable respectively. Twenty-eight percent of patients felt tingling sensations during treatment. After treatment, 79 % of patients’ expectations were met. Most patients experienced an (better than) expected level of side effects (75 %), participation in daily- (83 %) and social activity (86 %) and symptoms (78 %). However, 33 % expected more treatment efficacy than experienced. Conclusion: Treatment on the 1.5 T MR-Linac is well tolerated and meets patient expectations. Despite the fact that some patients expected greater treatment efficacy and the frequent occurrence of tingling sensations during treatment, most patient experiences were comparable or better than previously expected.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2405632423000240Test; https://doaj.org/toc/2405-6324Test

الوصول الحر: https://doaj.org/article/c6e800c704d4408fa9e812deaee34bfaTest

المؤلفون: Clifton Fuller

مصطلحات موضوعية: Radiology and organ imaging, Radiation therapy, Medical physics, Mr-Linac, MR-guided radiotherapy (MRgRT), head and neck cancer, Adaptive radiotherapy (ART), MR biomarkers, Diffusion-Weighted Imaging (DWI

الوصف: Presentation to the European SocieTy for Radiotherapy and Oncology 2024 CERRO workshop, on 2024-01-17, Le Chalet du Mont Vallon, Ménuires, FR.

العلاقة: https://figshare.com/articles/presentation/CERRO_2024_MR_Biomarkers_in_head_and_neck_cancer_/25061414Test

الإتاحة: https://doi.org/10.6084/m9.figshare.25061414.v1Test
https://figshare.com/articles/presentation/CERRO_2024_MR_Biomarkers_in_head_and_neck_cancer_/25061414Test

المؤلفون: Sydney Wolfe, Marshall A. Diven, Ariel E. Marciscano, Xi Kathy Zhou, A. U. Kishan, M. L. Steinberg, Joseph A. Miccio, Philip Camilleri, Himanshu Nagar

المصدر: BMC Cancer, Vol 23, Iss 1, Pp 1-11 (2023)

مصطلحات موضوعية: Prostate cancer (PCa), Definitive radiotherapy, Stereotactic body radiotherapy (SBRT), Magnetic resonance linear accelerator (MR-LINAC), MR-guided radiotherapy (MRgRT), Gastrointestinal (GI), Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: Abstract Background Ultra-hypofractionated regimens for definitive prostate cancer (PCa) radiotherapy are increasingly utilized due in part to promising safety and efficacy data complemented by greater patient convenience from a treatment course requiring fewer sessions. As such, stereotactic body radiation therapy (SBRT) is rapidly emerging as a standard definitive treatment option for patients with localized PCa. The commercially available magnetic resonance linear accelerator (MR-LINAC) integrates MR imaging with radiation delivery, providing several theoretical advantages compared to computed tomography (CT)-guided radiotherapy. MR-LINAC technology facilitates improved visualization of the prostate, real-time intrafraction tracking of prostate and organs-at-risk (OAR), and online adaptive planning to account for target movement and anatomical changes. These features enable reduced treatment volume margins and improved sparing of surrounding OAR. The theoretical advantages of MR-guided radiotherapy (MRgRT) have recently been shown to significantly reduce rates of acute grade ≥ 2 GU toxicities as reported in the prospective randomized phase III MIRAGE trial, which compared MR-LINAC vs CT-based 5 fraction SBRT in patients with localized PCa (Kishan et al. JAMA Oncol 9:365-373, 2023). Thus, MR-LINAC SBRT–utilizing potentially fewer treatments–is warranted and clinically relevant for men with low or intermediate risk PCa electing for radiotherapy as definitive treatment. Methods/Design A total of 136 men with treatment naïve low or intermediate risk PCa will be randomized in a 1:1 ratio to 5 or 2 fractions of MR-guided SBRT using permuted block randomization. Randomization is stratified by baseline Expanded PCa Index Composite (EPIC) bowel and urinary domain scores. Patients undergoing 5 fractions will receive 37.5 Gy to the prostate over 10–14 days and patients undergoing 2 fractions will receive 25 Gy to the prostate over 7–10 days. The co-primary endpoints are GI and GU toxicities as measured by change scores in the bowel and urinary EPIC domains, respectively. The change scores will be calculated as pre-treatment (baseline) score subtracted from the 2-year score. Discussion FORT is an international, multi-institutional prospective randomized phase II trial evaluating whether MR-guided SBRT delivered in 2 fractions versus 5 fractions is non-inferior from a gastrointestinal (GI) and genitourinary (GU) toxicity standpoint at 2 years post-treatment in men with low or intermediate risk PCa. Trial registration Clinicaltrials.gov identifier: NCT04984343 . Date of registration: July 30, 2021. Protocol version: 4.0, Nov 8, 2022.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/1471-2407Test

الوصول الحر: https://doaj.org/article/4a4a3863bd8f42239a16fcb311ad2f5aTest

المؤلفون: Ariel E. Marciscano, Sydney Wolfe, Xi Kathy Zhou, Christopher E. Barbieri, Silvia C. Formenti, Jim C. Hu, Ana M. Molina, David M. Nanus, Jones T. Nauseef, Douglas S. Scherr, Cora N. Sternberg, Scott T. Tagawa, Himanshu Nagar

المصدر: BMC Cancer, Vol 23, Iss 1, Pp 1-9 (2023)

مصطلحات موضوعية: Prostate cancer, Salvage radiotherapy, Stereotactic body radiotherapy (SBRT), MR-Linac, MRI-guided radiotherapy (MRgRT), Genitourinary, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282

الوصف: Abstract Background Ultra-hypofractionated image-guided stereotactic body radiotherapy (SBRT) is increasingly used for definitive treatment of localized prostate cancer. Magnetic resonance imaging-guided radiotherapy (MRgRT) facilitates improved visualization, real-time tracking of targets and/or organs-at-risk (OAR), and capacity for adaptive planning which may translate to improved targeting and reduced toxicity to surrounding tissues. Given promising results from NRG-GU003 comparing conventional and moderate hypofractionation in the post-operative setting, there is growing interest in exploring ultra-hypofractionated post-operative regimens. It remains unclear whether this can be done safely and whether MRgRT may help mitigate potential toxicity. SHORTER (NCT04422132) is a phase II randomized trial prospectively evaluating whether salvage MRgRT delivered in 5 fractions versus 20 fractions is non-inferior with respect to gastrointestinal (GI) and genitourinary (GU) toxicities at 2-years post-treatment. Methods A total of 136 patients will be randomized in a 1:1 ratio to salvage MRgRT in 5 fractions or 20 fractions using permuted block randomization. Patients will be stratified according to baseline Expanded Prostate Cancer Index Composite (EPIC) bowel and urinary domain scores as well as nodal treatment and androgen deprivation therapy (ADT). Patients undergoing 5 fractions will receive a total of 32.5 Gy over 2 weeks and patients undergoing 20 fractions will receive a total of 55 Gy over 4 weeks, with or without nodal coverage (25.5 Gy over 2 weeks and 42 Gy over 4 weeks) and ADT as per the investigator’s discretion. The co-primary endpoints are change scores in the bowel and the urinary domains of the EPIC. The change scores will reflect the 2-year score minus the pre-treatment (baseline) score. The secondary endpoints include safety endpoints, including change in GI and GU symptoms at 3, 6, 12 and 60 months from completion of treatment, and efficacy endpoints, including time to progression, prostate cancer specific survival and overall survival. Discussion The SHORTER trial is the first randomized phase II trial comparing toxicity of ultra-hypofractionated and hypofractionated MRgRT in the salvage setting. The primary hypothesis is that salvage MRgRT delivered in 5 fractions will not significantly increase GI and GU toxicities when compared to salvage MRgRT delivered in 20 fractions. Trial registration ClinicalTrials.gov Identifier: NCT04422132. Date of registration: June 9, 2020.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/1471-2407Test

الوصول الحر: https://doaj.org/article/fa243c6550cd4849bd0e24f9ff480799Test