{"id":182,"date":"2023-10-24T17:30:10","date_gmt":"2023-10-24T15:30:10","guid":{"rendered":"https:\/\/physicsworld.com\/?p=110776"},"modified":"2024-01-23T11:24:55","modified_gmt":"2024-01-23T10:24:55","slug":"proton-therapy-on-an-upward-trajectory-while-flash-treatment-schemes-get-ready-to-shine","status":"publish","type":"post","link":"https:\/\/hadamard.com\/c\/proton-therapy-on-an-upward-trajectory-while-flash-treatment-schemes-get-ready-to-shine\/","title":{"rendered":"Proton therapy on an upward trajectory while FLASH treatment schemes get ready to shine"},"content":{"rendered":"<p>While proton therapy has well and truly arrived as a mainstream treatment option in radiation oncology \u2013 there are currently 42 operational proton facilities in the US and a further 13 centres under construction \u2013 it\u2019s evident that the clinical innovation is only just getting started when it comes to at-scale deployment of protons for the treatment of cancer. That\u2019s one of the key take-aways to emerge from a dedicated conference session \u2013 Innovative Radiation Therapy Approaches: Benefits, Challenges, Global Perspective \u2013 at the <a href=\"https:\/\/www.astro.org\/Meetings-and-Education\/Micro-Sites\/2023\/Annual-Meeting\">ASTRO Annual Meeting<\/a> in San Diego, CA, earlier this month.<\/p>\n<p>In terms of precision targeting, the case for proton therapy versus conventional radiotherapy is clear enough. Think similar tumour-killing properties as photons, but with markedly decreased dose to normal tissue. All of which helps the radiation oncology team treat tumours close to organs-at-risk (OARs), with the potential for decreased side-effects and complications along the way.<\/p>\n<p>\u201cProtons release all their energy at a point and then they stop,\u201d explained James Metz, chair of <a href=\"https:\/\/www.xrt.upenn.edu\/\">radiation oncology at the University of Pennsylvania<\/a> (UPenn) and executive director of the <a href=\"https:\/\/www.oncolink.org\/\">OncoLink<\/a> cancer education service. That means no radiation dose beyond the target as well as far less dose deposited in front of the target compared with photon and electron irradiation.<\/p>\n<figure id=\"attachment_110780\" class=\"size-thumbnail\"><a title=\"Click to open image in popup\" href=\"https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz.jpg\" data-featherlight=\"image\"><img loading=\"lazy\" decoding=\"async\" class=\"attachment-thumbnail size-thumbnail\" src=\"https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-285x317.jpg\" sizes=\"auto, (max-width: 285px) 100vw, 285px\" srcset=\"https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-285x317.jpg 285w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-190x211.jpg 190w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-768x853.jpg 768w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-360x400.jpg 360w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-371x412.jpg 371w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-369x410.jpg 369w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-635x706.jpg 635w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-177x197.jpg 177w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-174x193.jpg 174w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-225x250.jpg 225w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-81x90.jpg 81w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz-115x128.jpg 115w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/James-Metz.jpg 900w\" alt=\"James Metz\" width=\"285\" height=\"317\" \/><\/a><script type=\"application\/json\">\"\\u003Cstrong\\u003EJames Metz\\u003C\\\/strong\\u003E \\u201cWe need to systematically evaluate the clinical potential and define it through rigorous science.\\u201d (Courtesy: UPenn)\"<\/script><figcaption class=\"gallery-item__caption\"><strong>James Metz<\/strong> \u201cWe need to systematically evaluate the clinical potential and define it through rigorous science.\u201d (Courtesy: UPenn)<\/figcaption><\/figure>\n<p>As such, clinicians are able to target the tumour layer-by-layer with pencil-beam-scanned proton delivery. \u201cWe take a tumour, divide it up voxel-by-voxel into 5 mm<sup>3<\/sup> volumes and take this pencil beam and treat [complex structures] spot-by-spot with absolutely no exit dose,\u201d Metz noted. \u201cProtons give us the opportunity to reduce dose to normal structures, to combine with chemotherapy and immunotherapy, and to increase [radiation] doses going forwards.\u201d<\/p>\n<p>Notwithstanding the ongoing roll-out of proton therapy systems across the developed world \u2013 clinical uptake is similar for the US, Europe and Asia, although currently there\u2019s only one proton treatment centre in sub-Saharan Africa \u2013 it\u2019s apparent that \u201cgold-standard\u201d evidence for the clinical efficacy of protons is still a work-in-progress. \u201cWe need to systematically evaluate the clinical potential and define it through rigorous science \u2013 quantifying the benefits versus investment,\u201d argued Metz. \u201cAfter all, substantial resource and infrastructure are needed to support a proton therapy centre.\u201d<\/p>\n<p>The evidence is coming \u2013 and sooner than later. A number of randomized phase III clinical trials are accruing data or have recently closed for diverse cancer indications (including lung, oesophageal, liver, head-and-neck and brain). Meanwhile, pragmatic trials are also accruing well and evaluating proton treatments in routine clinical practice for patients with breast cancer and prostate cancer.<\/p>\n<h3><strong>FLASH the disruptor<\/strong><\/h3>\n<p>&nbsp;<\/p>\n<p>Metz, for his part, is one of the clinical pioneers of proton therapy, having led the development programme for the <a href=\"https:\/\/www.pennmedicine.org\/cancer\/navigating-cancer-care\/programs-and-centers\/roberts-proton-therapy-center\">Roberts Proton Therapy Center<\/a> in Philadelphia \u2013 a facility that has treated thousands of cancer patients using protons since it opened its doors in 2010. Clinical innovation being what it is, however, attention is already turning to what\u2019s being touted as the \u201cnext big thing\u201d in particle therapy: FLASH proton therapy.<\/p>\n<p>&nbsp;<\/p>\n<p>For context, FLASH is an experimental treatment modality that involves ultrahigh-dose rate delivery (above 60\u201380 Gy\/s) of ionizing radiation (electron, photon or proton) over very short durations (less than 1 s). Preclinical studies have shown that FLASH radiotherapy is less toxic to normal tissues and as effective as conventional radiotherapy at destroying tumours. If broadly validated, FLASH treatment schemes therefore have the potential to revolutionize radiotherapy \u2013 such that higher doses could be delivered safely to tumours or established doses be given with reduced toxicity to OARs.<\/p>\n<p>&nbsp;<\/p>\n<p>In short, FLASH proton therapy is shaping up as a future disruptor in radiation oncology, argued Metz, \u201cbringing together biology and technology in new ways\u2026and turning radiobiology on its head a bit\u201d. The upsides are already coming into view.\u00a0 For starters, FLASH proton therapy could significantly compress radiation treatment times, such that radiotherapy becomes more like a surgical procedure.<\/p>\n<p>That\u2019s good news for the patient along several coordinates \u2013 opening a path to improved quality-of-life, reduced toxicity and side-effects, as well as much less time spent in the clinic. At a more fundamental level, FLASH irradiation can also trigger different immune pathways and gene expression, creating novel opportunities for drug and radiation combinations.<\/p>\n<p>Yet while FLASH has the potential to upend treatment paradigms and many current assumptions about radiation delivery, Metz concluded on a cautionary note: \u201cI would say FLASH proton therapy is not yet ready for prime-time\u2026[and] not ready to be deployed further than a few highly resourced centres that can complete the appropriate research and clinical trials.\u201d<\/p>\n<div class=\"box-section\">\n<h2 class=\"box-section__title\">Clinical innovation: it\u2019s all about outcomes<\/h2>\n<p>Alongside the clinical opportunities afforded by proton therapy, the ASTRO session on Innovative Radiation Therapy Approaches covered plenty of other bases. Tamer Refaat, professor of <a href=\"https:\/\/ssom.luc.edu\/radiation-oncology\/\">radiation oncology at Loyola University<\/a> in Chicago, Illinois, kicked off with a status report on MR-guided radiotherapy (MRgRT).<\/p>\n<p>&nbsp;<\/p>\n<p>\u201cThe big deal [with MRgRT] is real-time adaptation,\u201d Refaat told delegates. In other words, personalized, daily-adapted radiotherapy that\u2019s based on real-time and on-table patient anatomy, allowing the clinical team to maximize dose to the target volume and minimize dose to OARs.<\/p>\n<p>As for MRgRT innovations to watch, Refaat highlighted the commercial and clinical roll-out of cine-gating functionality to enhance the treatment of upper abdominal tumours on a single phase of breathing. \u201cThe radiation beam turns on whenever the target is within the tracking boundary and turns off when outside,\u201d he explained (adding that the downside is longer time on the treatment table for the patient).<\/p>\n<figure id=\"attachment_110779\" class=\"size-thumbnail wp-image-110779\"><a title=\"Click to open image in popup\" href=\"https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat.jpg\" data-featherlight=\"image\"><img loading=\"lazy\" decoding=\"async\" class=\"size-thumbnail wp-image-110779\" src=\"https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-295x317.jpg\" sizes=\"auto, (max-width: 295px) 100vw, 295px\" srcset=\"https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-295x317.jpg 295w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-197x211.jpg 197w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-768x824.jpg 768w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-373x400.jpg 373w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-384x412.jpg 384w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-382x410.jpg 382w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-635x681.jpg 635w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-184x197.jpg 184w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-180x193.jpg 180w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-233x250.jpg 233w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-84x90.jpg 84w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat-119x128.jpg 119w, https:\/\/physicsworld.com\/wp-content\/uploads\/2023\/10\/Tamer-Refaat.jpg 847w\" alt=\"Tamer Refaat\" width=\"295\" height=\"317\" \/><\/a><script type=\"application\/json\">\"\\u003Cstrong\\u003ETamer Refaat\\u003C\\\/strong\\u003E \\u201cThe big deal [with MRgRT] is real-time adaptation.\\u201d (Courtesy: Loyola University)\"<\/script><\/figure>\n<p><strong>Tamer Refaat<\/strong> \u201cThe big deal [with MRgRT] is real-time adaptation.\u201d (Courtesy: Loyola University)Incorporation of functional MRgRT into the MR-Linac workflow also came under the spotlight, with Refaat citing researchers at <a href=\"https:\/\/www.mdanderson.org\/\">MD Anderson Cancer Center<\/a> (Houston, Texas) among the early-adopters seeking to identify radioresistant tumour subvolumes and escalate dose to those subvolumes accordingly.<\/p>\n<p>Another hot topic centred on the combined-modality synergies of integrating immunotherapy and radiotherapy cancer treatments. The speaker, Silvia Formenti, a radiation oncologist at <a href=\"https:\/\/weill.cornell.edu\/\">Weill Cornell Medicine<\/a> in New York, is one of the main-movers behind a paradigm shift in radiobiology, her efforts elucidating the role of ionizing radiation on the immune system while demonstrating the efficacy of combined radiotherapy\u2013immunotherapy regimes in solid tumours.<\/p>\n<p>Formenti highlighted the pivotal role played in this regard by the ImmunoRad Radiation Oncology-Biology Integration Network (<a href=\"https:\/\/www.immunorobin.org\/\">ROBIN<\/a>). A multidisciplinary R&amp;D collaboration between US and European cancer centres, ROBIN is seeking to better understand the interaction of radiation therapy and the immune response \u2013 as well as nurturing the talent pipeline of early-career scientists into the field. Right now, noted Formenti, the bigger picture is clouded by \u201cfinancial toxicity\u201d, with the cost of immunotherapy proving prohibitive for most low- and middle-income nations \u2013 as well as many Americans.<\/p>\n<p>The focus on collaborative clinical research was echoed by Stephen Harrow, a consultant clinical oncologist at the <a href=\"https:\/\/www.med.scot.nhs.uk\/trainee-doctors\/specialties\/oncology\">Edinburgh Cancer Centre<\/a> in Scotland. In the final talk of the session, he discussed the application of stereotactic body radiotherapy (SBRT) for oligometastatic disease.<\/p>\n<p>Post-pandemic, Harrow highlighted how the Scottish Oligomet SABR Network (SOSN), aided by \u00a31 million of Scottish government funding, has enabled Scotland\u2019s five cancer centres to offer a joined-up SBRT treatment service to patients across the country (not just the highly populated central belt encompassing Glasgow and Edinburgh).<\/p>\n<p>The goal of SOSN, he explained, is to \u201cbuild a network of physicians, physicists and radiographers so that we\u2019re all agreed on patient selection [criteria for SBRT] and we have equity for patients across the country\u201d. What\u2019s more, he added, \u201cthe evidence is definitely building that you can influence patient outcomes with SBRT for oligomet disease.\u201d<\/p>\n<p>&nbsp;<\/p>\n<\/div>\n<p>The post <a href=\"https:\/\/physicsworld.com\/a\/proton-therapy-on-an-upward-trajectory-while-flash-treatment-schemes-get-ready-to-shine\/\" rel=\"nofollow\">Proton therapy on an upward trajectory while FLASH treatment schemes get ready to shine<\/a> appeared first on <a href=\"https:\/\/physicsworld.com\" rel=\"nofollow\">Physics World<\/a>.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>While proton therapy has well and truly arrived as a mainstream treatment option in radiation oncology \u2013 there are currently 42 operational proton facilities in the US and a further 13 centres under construction \u2013 it\u2019s evident that the clinical innovation is only just getting started when it comes to at-scale deployment of protons for&hellip; <a class=\"more-link\" href=\"https:\/\/hadamard.com\/c\/proton-therapy-on-an-upward-trajectory-while-flash-treatment-schemes-get-ready-to-shine\/\">Continue reading <span class=\"screen-reader-text\">Proton therapy on an upward trajectory while FLASH treatment schemes get ready to shine<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-182","post","type-post","status-publish","format-standard","hentry","category-allgemein","entry"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/posts\/182","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/comments?post=182"}],"version-history":[{"count":1,"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/posts\/182\/revisions"}],"predecessor-version":[{"id":553,"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/posts\/182\/revisions\/553"}],"wp:attachment":[{"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/media?parent=182"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/categories?post=182"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hadamard.com\/c\/wp-json\/wp\/v2\/tags?post=182"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}