{"entity":{"id":"radiation-roadmap","kind":"roadmap","name":"Radiotherapy roadmap: X-rays → shaped beams → fewer fractions, particles and FLASH","aka":[],"tldr":"Radiotherapy cures more people than any drug and has reinvented itself every decade: from crude X-ray fields to beams shaped by computer, delivered in days instead of weeks, and now in fractions of a second. Its future is precision, fewer visits, and combination with drugs that make radiation work better.","summary":"External beam radiotherapy moved from two-dimensional fields to three-dimensional conformal plans, intensity modulation, daily image guidance and stereotactic delivery that ablates a tumour in one to five sessions. Large randomised trials showed that fewer, larger fractions are as effective and as safe in breast and prostate cancer, cutting a course from weeks to days; protons and carbon ions spare tissue behind the tumour; MR-linacs adapt the plan to the anatomy of the day.\n\nThe present decade is about combination and de-escalation. Immunotherapy after chemoradiation is standard in stage III lung cancer (PACIFIC) and locally advanced cervical cancer (KEYNOTE-A18), and a targeted pill after chemoradiation in EGFR-mutant lung cancer (LAURA); several attempts to add drugs to head and neck chemoradiation failed, and de-escalation for HPV-positive throat cancer fell short. Single-fraction palliative treatment, skipping radioactive iodine in low-risk thyroid cancer and lower doses in children's brain tumours are the de-escalation wins.\n\nAhead are FLASH radiotherapy, which delivers the whole dose in under a second and spares normal tissue in animals, very-high-energy electrons, proton arcs, upright treatment, AI planning and radiation as an immune primer. The pace is set by the underfunding of radiotherapy research relative to drugs, and by the machines, physicists and technicians that most of the world does not have.","asOf":"2026-09-10","links":[{"label":"FAST-Forward: five-fraction breast radiotherapy (Lancet 2020)","url":"https://doi.org/10.1016/S0140-6736(20)30932-6"},{"label":"PACIFIC (NEJM 2017)","url":"https://www.nejm.org/doi/full/10.1056/NEJMoa1709937"},{"label":"Lancet Oncology Commission: expanding global access to radiotherapy (2015)","url":"https://doi.org/10.1016/S1470-2045(15)00222-3"}],"tags":[],"related":["radiopharma-roadmap","idea-acc-single-fraction-palliative-radiotherapy-default","idea-acc-hypofractionation-default-lmic","idea-acc-pooled-procurement-radiotherapy","idea-acc-linac-uptime-contracts","idea-acc-remote-planning-hubs","idea-acc-remote-medical-physics-qa","idea-acc-frugal-hdr-brachytherapy","idea-bio2-radiotherapy-sting-fractionation","idea-cthpv-adapted-deescalation","frontier-2035","devices-roadmap"],"cancers":[],"sections":["radiation"],"technologies":["imrt-igrt","sbrt","brachytherapy","proton-therapy","carbon-ion","mr-linac","flash-rt","vhee-radiotherapy","proton-arc-therapy","lattice-radiotherapy","bnct","hyperthermia","radiodynamic-therapy","radioimmunotherapy","targeted-alpha-therapy","radionuclide-parp-combination","auto-contouring-ai","treatment-planning-systems","palliative-radiotherapy","prophylactic-cranial-irradiation","intraoperative-radiotherapy","hyperbaric-oxygen-radiation-injury","acupuncture-xerostomia"],"targets":[],"drugs":["durvalumab","temozolomide","radioactive-iodine","amifostine"],"companies":["varian","elekta","reflexion","theryq","iba","mevion","raysearch","leo-cancer-care","p-cure","tae-life-sciences","neutron-therapeutics","limbus-ai","therapanacea","nrg-oncology"],"institutions":["the-christie","institut-curie","mayo-clinic-florida","mgh"],"pathways":[],"terms":["hypofractionation"],"trials":["pacific","laura","keynote-a18","cross","interlace","portec-3","convert","javelin-hn-100","trilynx","nrg-hn002-hn005","estimabl2","acns0331","eortc-26981"],"people":[],"bottlenecks":["b-surgery-radiation-innovation","b-global-access","b-workforce","b-trial-design"],"keyPapers":["paper-atun-lancet-oncol","paper-murray-brunt-lancet"],"journals":[],"dependsOn":[],"notes":[],"steps":[{"era":"1895-1990s","title":"From X-rays to conformal beams","description":"Röntgen's X-rays were used against cancer within a year of their discovery, and the Curies' radium became brachytherapy. Cobalt units and then linear accelerators (1950s) delivered higher energies deeper; CT planning in the 1980s let beams be shaped to the tumour in three dimensions. Radioactive iodine for thyroid cancer, from the 1940s, was the first targeted radiotherapy and a preview of the radiopharmaceutical field.","refs":["institut-curie","brachytherapy","radioactive-iodine","imrt-igrt"],"status":"historic"},{"era":"2000s-2020","title":"Modulation, image guidance and fewer fractions","description":"Intensity-modulated and image-guided radiotherapy shaped dose around organs and checked position daily, cutting late toxicity in prostate and head and neck cancer. Stereotactic body radiotherapy ablated early lung cancers and oligometastases in one to five sessions. Large trials proved that fewer, larger fractions match conventional courses: CHHiP in prostate cancer and FAST-Forward (2020), which delivered breast radiotherapy in five sessions over one week. CONVERT settled the small-cell lung schedule debate. Treatment planning software became the real product.","refs":["imrt-igrt","sbrt","hypofractionation","convert","treatment-planning-systems","varian","elekta","raysearch"],"status":"historic"},{"era":"2017-2026","title":"Radiation plus drugs: what worked and what did not","description":"PACIFIC made a year of durvalumab after chemoradiation the standard in stage III lung cancer; KEYNOTE-A18 added pembrolizumab to curative chemoradiation for cervical cancer with a survival gain; LAURA gave osimertinib after chemoradiation in EGFR-mutant lung cancer; INTERLACE showed that six weeks of cheap chemotherapy before cervical chemoradiation cuts deaths. The failures were as instructive: adding a PD-L1 blocker to head and neck chemoradiation did not help (JAVELIN HN 100), a promising radiosensitiser made things worse (TrilynX), and de-escalating radiation for HPV-positive throat cancer fell short (NRG-HN002 and HN005).","refs":["pacific","durvalumab","keynote-a18","laura","interlace","cross","portec-3","javelin-hn-100","trilynx","nrg-hn002-hn005","temozolomide","eortc-26981"],"status":"current"},{"era":"2010s-2026","title":"Particles, magnets and adaptation","description":"Protons stop inside the tumour rather than passing through, which matters most in children and near critical organs; the Christie opened the UK's first NHS proton centre and compact single-room systems are spreading. Carbon ions kill radioresistant tumours and are available at a handful of centres, with North America's first being built at Mayo Clinic Florida. MR-linacs image soft tissue during treatment and adapt the plan daily; PET-guided systems track the tumour by its own emissions. AI auto-contouring now saves hours per plan in hundreds of centres. Clinical proton dose is still reported at RBE 1.1; whether LET-weighted RBE plus tissue alpha/beta can pick the adults who benefit versus IMRT is untested in the randomised trials now running.","refs":["proton-therapy","the-christie","mgh","iba","mevion","carbon-ion","mayo-clinic-florida","mr-linac","elekta","reflexion","auto-contouring-ai","limbus-ai","therapanacea","linear-energy-transfer","relative-biological-effectiveness","idea-bio2-let-rbe-ab-selects-protons"],"status":"current"},{"era":"2016-2026","title":"Doing less: fewer visits and fewer treatments","description":"Single-fraction radiotherapy relieves bone pain as well as ten fractions and is still under-used. ESTIMABL2 showed that most low-risk thyroid cancers can skip radioactive iodine after surgery. ACNS0331 tested lower doses and smaller fields in children with medulloblastoma to reduce cognitive harm. MRI surveillance is replacing prophylactic brain irradiation in small-cell lung cancer. In overloaded systems, one-week hypofractionated courses are the single largest capacity gain available.","refs":["palliative-radiotherapy","idea-acc-single-fraction-palliative-radiotherapy-default","estimabl2","acns0331","prophylactic-cranial-irradiation","idea-acc-hypofractionation-default-lmic","idea-cthpv-adapted-deescalation"],"status":"current"},{"era":"2026-2032","title":"FLASH, arcs, upright and new particles","description":"FLASH radiotherapy delivers a full dose in under a second and, in animals, spares normal tissue while killing tumour; the first human trials of FLASH protons have been run and dedicated electron machines are being built. Very-high-energy electrons and proton arcs are routes to deep FLASH. Upright treatment chairs could cut the cost of particle therapy; boron neutron capture therapy, approved in Japan for head and neck cancer, needs compact neutron sources; lattice radiotherapy deliberately doses a large tumour unevenly. Each is limited by engineering and dosimetry rather than biology.","refs":["flash-rt","theryq","varian","vhee-radiotherapy","proton-arc-therapy","leo-cancer-care","p-cure","bnct","tae-life-sciences","neutron-therapeutics","lattice-radiotherapy","radiodynamic-therapy","hyperthermia"],"status":"emerging"},{"era":"2028+","title":"Radiation as an immune primer, and radiation from inside","description":"Radiation releases tumour antigens and can switch on the innate immune alarm, or switch it off, depending on dose and fractionation; trials are trying to find the schedule that primes rather than suppresses. Systemic radiation is the radiopharmaceutical roadmap: radioligands, radio-antibodies and alpha emitters that deliver dose to every metastasis, increasingly combined with DNA-repair inhibitors. The two fields are converging on the same question: how to kill the last cell wherever it is.","refs":["idea-bio2-radiotherapy-sting-fractionation","radiopharma-roadmap","radioimmunotherapy","targeted-alpha-therapy","radionuclide-parp-combination","frontier-2035"],"status":"speculative"},{"era":"What sets the pace","title":"Machines, physicists and money","description":"Radiotherapy cures a large share of all cured patients and receives a small share of research funding. Most of the world's population lacks access to a working linear accelerator, and where machines exist they are idle for want of physicists and maintenance. Pooled procurement of machines and service, contracts that pay for uptime rather than hardware, remote planning hubs and remote quality assurance, and low-cost brachytherapy for cervical cancer in every regional centre are the proposals that would change that.","refs":["b-surgery-radiation-innovation","b-global-access","b-workforce","b-trial-design","idea-acc-pooled-procurement-radiotherapy","idea-acc-linac-uptime-contracts","idea-acc-remote-planning-hubs","idea-acc-remote-medical-physics-qa","idea-acc-frugal-hdr-brachytherapy"],"status":"current"}],"watch":[]},"route":"/roadmaps/radiation-roadmap/","neighbours":{"roadmap":[{"id":"devices-roadmap","kind":"roadmap","name":"Devices and physical therapies roadmap: heat and light → electric fields and focused sound → drug-releasing implants","route":"/roadmaps/devices-roadmap/"},{"id":"global-access-roadmap","kind":"roadmap","name":"Global access and affordability roadmap: essential medicines and generics → biosimilars and frugal trials → reliance, pooling and homegrown innovation","route":"/roadmaps/global-access-roadmap/"},{"id":"lung-cancer-evidence-roadmap","kind":"roadmap","name":"Lung cancer roadmap: from Doll and Hill and the naming of tobacco, through the cytotoxic plateau, computed tomography screening, EGFR and ALK, immunotherapy by PD-L1, the perioperative trials and PACIFIC, to DLL3 in small-cell disease and a 2032 registry watch","route":"/roadmaps/lung-cancer-evidence-roadmap/"},{"id":"lymphoma-roadmap","kind":"roadmap","name":"Lymphoma roadmap: from a jaw tumour in Uganda and the first human cancer virus to gene-expression subtypes, PET-adapted chemotherapy, CAR-T cells, bispecific antibodies and the genetics-directed trials now recruiting","route":"/roadmaps/lymphoma-roadmap/"},{"id":"frontier-2035","kind":"roadmap","name":"Radical oncology: what could change the war by 2035","route":"/roadmaps/frontier-2035/"},{"id":"radiopharma-roadmap","kind":"roadmap","name":"Radiopharmaceutical roadmap: iodine → lutetium → actinium","route":"/roadmaps/radiopharma-roadmap/"}],"idea":[{"id":"idea-acc-pooled-procurement-radiotherapy","kind":"idea","name":"A Gavi-style pooled purchaser for radiotherapy equipment and service","route":"/ideas/idea-acc-pooled-procurement-radiotherapy/"},{"id":"idea-cthpv-adapted-deescalation","kind":"idea","name":"ctHPV-DNA-adapted de-escalation of chemoradiation","route":"/ideas/idea-cthpv-adapted-deescalation/"},{"id":"idea-acc-frugal-hdr-brachytherapy","kind":"idea","name":"Low-cost cobalt-60 brachytherapy for cervical cancer in every regional centre","route":"/ideas/idea-acc-frugal-hdr-brachytherapy/"},{"id":"idea-acc-hypofractionation-default-lmic","kind":"idea","name":"Make one-week radiotherapy the default in overloaded systems","route":"/ideas/idea-acc-hypofractionation-default-lmic/"},{"id":"idea-acc-remote-medical-physics-qa","kind":"idea","name":"One medical physicist covering many radiotherapy machines through remote quality assurance","route":"/ideas/idea-acc-remote-medical-physics-qa/"},{"id":"idea-acc-linac-uptime-contracts","kind":"idea","name":"Pay for radiotherapy machine uptime, not for the machine","route":"/ideas/idea-acc-linac-uptime-contracts/"},{"id":"idea-bio2-radiotherapy-sting-fractionation","kind":"idea","name":"Pick the radiation dose that switches the immune alarm on, not off","route":"/ideas/idea-bio2-radiotherapy-sting-fractionation/"},{"id":"idea-acc-remote-planning-hubs","kind":"idea","name":"Round-the-clock remote treatment-planning hubs for clinics without physicists","route":"/ideas/idea-acc-remote-planning-hubs/"},{"id":"idea-acc-single-fraction-palliative-radiotherapy-default","kind":"idea","name":"Single-fraction radiotherapy as the default for painful bone metastases","route":"/ideas/idea-acc-single-fraction-palliative-radiotherapy-default/"},{"id":"idea-bio2-let-rbe-ab-selects-protons","kind":"idea","name":"Use LET, RBE and alpha/beta to decide when protons beat IMRT","route":"/ideas/idea-bio2-let-rbe-ab-selects-protons/"}],"section":[{"id":"radiation","kind":"section","name":"Radiation Therapy","route":"/fronts/radiation/"}],"technology":[{"id":"acupuncture-xerostomia","kind":"technology","name":"Acupuncture for dry mouth after head and neck radiotherapy","route":"/technologies/acupuncture-xerostomia/"},{"id":"auto-contouring-ai","kind":"technology","name":"AI auto-contouring and adaptive planning","route":"/technologies/auto-contouring-ai/"},{"id":"bnct","kind":"technology","name":"Boron neutron capture therapy","route":"/technologies/bnct/"},{"id":"brachytherapy","kind":"technology","name":"Brachytherapy","route":"/technologies/brachytherapy/"},{"id":"carbon-ion","kind":"technology","name":"Carbon-ion therapy","route":"/technologies/carbon-ion/"},{"id":"flash-rt","kind":"technology","name":"FLASH radiotherapy","route":"/technologies/flash-rt/"},{"id":"hyperbaric-oxygen-radiation-injury","kind":"technology","name":"Hyperbaric oxygen for late radiation injury","route":"/technologies/hyperbaric-oxygen-radiation-injury/"},{"id":"hyperthermia","kind":"technology","name":"Hyperthermia","route":"/technologies/hyperthermia/"},{"id":"imrt-igrt","kind":"technology","name":"IMRT / IGRT (modern external beam)","route":"/technologies/imrt-igrt/"},{"id":"intraoperative-radiotherapy","kind":"technology","name":"Intraoperative radiotherapy (IORT)","route":"/technologies/intraoperative-radiotherapy/"},{"id":"lattice-radiotherapy","kind":"technology","name":"Lattice and GRID radiotherapy","route":"/technologies/lattice-radiotherapy/"},{"id":"mr-linac","kind":"technology","name":"MR-guided adaptive radiotherapy","route":"/technologies/mr-linac/"},{"id":"palliative-radiotherapy","kind":"technology","name":"Palliative radiotherapy","route":"/technologies/palliative-radiotherapy/"},{"id":"prophylactic-cranial-irradiation","kind":"technology","name":"Prophylactic cranial irradiation vs MRI surveillance","route":"/technologies/prophylactic-cranial-irradiation/"},{"id":"proton-arc-therapy","kind":"technology","name":"Proton arc therapy","route":"/technologies/proton-arc-therapy/"},{"id":"proton-therapy","kind":"technology","name":"Proton therapy","route":"/technologies/proton-therapy/"},{"id":"radioimmunotherapy","kind":"technology","name":"Radio-antibody & radio-ADC","route":"/technologies/radioimmunotherapy/"},{"id":"radiodynamic-therapy","kind":"technology","name":"Radiodynamic therapy and radiosensitising nanoparticles","route":"/technologies/radiodynamic-therapy/"},{"id":"radionuclide-parp-combination","kind":"technology","name":"Radioligand plus DNA-repair inhibitor combinations","route":"/technologies/radionuclide-parp-combination/"},{"id":"treatment-planning-systems","kind":"technology","name":"Radiotherapy treatment planning and QA software","route":"/technologies/treatment-planning-systems/"},{"id":"sbrt","kind":"technology","name":"SBRT / SABR (stereotactic radiotherapy)","route":"/technologies/sbrt/"},{"id":"targeted-alpha-therapy","kind":"technology","name":"Targeted alpha therapy","route":"/technologies/targeted-alpha-therapy/"},{"id":"vhee-radiotherapy","kind":"technology","name":"Very-high-energy electron therapy","route":"/technologies/vhee-radiotherapy/"}],"drug":[{"id":"amifostine","kind":"drug","name":"Amifostine","route":"/drugs/amifostine/"},{"id":"durvalumab","kind":"drug","name":"Durvalumab","route":"/drugs/durvalumab/"},{"id":"radioactive-iodine","kind":"drug","name":"Radioactive iodine (I-131)","route":"/drugs/radioactive-iodine/"},{"id":"temozolomide","kind":"drug","name":"Temozolomide","route":"/drugs/temozolomide/"}],"company":[{"id":"elekta","kind":"company","name":"Elekta","route":"/companies/elekta/"},{"id":"iba","kind":"company","name":"IBA (Ion Beam Applications)","route":"/companies/iba/"},{"id":"leo-cancer-care","kind":"company","name":"Leo Cancer Care","route":"/companies/leo-cancer-care/"},{"id":"limbus-ai","kind":"company","name":"Limbus AI","route":"/companies/limbus-ai/"},{"id":"mevion","kind":"company","name":"Mevion Medical Systems","route":"/companies/mevion/"},{"id":"neutron-therapeutics","kind":"company","name":"Neutron Therapeutics","route":"/companies/neutron-therapeutics/"},{"id":"nrg-oncology","kind":"company","name":"NRG Oncology","route":"/companies/nrg-oncology/"},{"id":"p-cure","kind":"company","name":"P-Cure","route":"/companies/p-cure/"},{"id":"raysearch","kind":"company","name":"RaySearch Laboratories","route":"/companies/raysearch/"},{"id":"reflexion","kind":"company","name":"RefleXion Medical","route":"/companies/reflexion/"},{"id":"tae-life-sciences","kind":"company","name":"TAE Life Sciences","route":"/companies/tae-life-sciences/"},{"id":"therapanacea","kind":"company","name":"TheraPanacea","route":"/companies/therapanacea/"},{"id":"theryq","kind":"company","name":"THERYQ","route":"/companies/theryq/"},{"id":"varian","kind":"company","name":"Varian (Siemens Healthineers)","route":"/companies/varian/"}],"institution":[{"id":"institut-curie","kind":"institution","name":"Institut Curie","route":"/institutions/institut-curie/"},{"id":"mgh","kind":"institution","name":"Massachusetts General Hospital Cancer Center","route":"/institutions/mgh/"},{"id":"mayo-clinic-florida","kind":"institution","name":"Mayo Clinic Comprehensive Cancer Center in Florida","route":"/institutions/mayo-clinic-florida/"},{"id":"the-christie","kind":"institution","name":"The Christie NHS Foundation Trust","route":"/institutions/the-christie/"}],"term":[{"id":"hypofractionation","kind":"term","name":"Hypofractionation (fewer, larger radiotherapy doses)","route":"/terms/hypofractionation/"},{"id":"linear-energy-transfer","kind":"term","name":"Linear energy transfer (LET)","route":"/terms/linear-energy-transfer/"},{"id":"relative-biological-effectiveness","kind":"term","name":"Relative biological effectiveness (RBE)","route":"/terms/relative-biological-effectiveness/"}],"trial":[{"id":"acns0331","kind":"trial","name":"COG ACNS0331","route":"/trials/acns0331/"},{"id":"convert","kind":"trial","name":"CONVERT","route":"/trials/convert/"},{"id":"cross","kind":"trial","name":"CROSS","route":"/trials/cross/"},{"id":"eortc-26981","kind":"trial","name":"EORTC 26981 / NCIC CE.3 (Stupp trial)","route":"/trials/eortc-26981/"},{"id":"estimabl2","kind":"trial","name":"ESTIMABL2","route":"/trials/estimabl2/"},{"id":"interlace","kind":"trial","name":"INTERLACE","route":"/trials/interlace/"},{"id":"javelin-hn-100","kind":"trial","name":"JAVELIN Head and Neck 100","route":"/trials/javelin-hn-100/"},{"id":"keynote-a18","kind":"trial","name":"KEYNOTE-A18 / ENGOT-cx11 / GOG-3047","route":"/trials/keynote-a18/"},{"id":"laura","kind":"trial","name":"LAURA","route":"/trials/laura/"},{"id":"nrg-hn002-hn005","kind":"trial","name":"NRG-HN002 & NRG-HN005 (HPV+ de-escalation)","route":"/trials/nrg-hn002-hn005/"},{"id":"pacific","kind":"trial","name":"PACIFIC","route":"/trials/pacific/"},{"id":"portec-3","kind":"trial","name":"PORTEC-3","route":"/trials/portec-3/"},{"id":"trilynx","kind":"trial","name":"TrilynX","route":"/trials/trilynx/"}],"bottleneck":[{"id":"b-global-access","kind":"bottleneck","name":"Most of the world has almost no cancer care","route":"/bottlenecks/b-global-access/"},{"id":"b-workforce","kind":"bottleneck","name":"Not enough oncologists, nurses, pathologists, physicists","route":"/bottlenecks/b-workforce/"},{"id":"b-surgery-radiation-innovation","kind":"bottleneck","name":"Surgery and radiotherapy cure most, get least","route":"/bottlenecks/b-surgery-radiation-innovation/"},{"id":"b-trial-design","kind":"bottleneck","name":"Trial design, endpoints and cost","route":"/bottlenecks/b-trial-design/"}],"paper":[{"id":"paper-atun-lancet-oncol","kind":"paper","name":"Expanding global access to radiotherapy","route":"/key-papers/paper-atun-lancet-oncol/"},{"id":"paper-murray-brunt-lancet","kind":"paper","name":"Hypofractionated breast radiotherapy for 1 week versus 3 weeks (FAST-Forward): 5-year efficacy and late normal tissue effects results from a multicentre, non-inferiority, randomised, phase 3 trial","route":"/key-papers/paper-murray-brunt-lancet/"},{"id":"paper-swedish-rectal-cancer-trial-preoperative-radiotherapy-nejm-1997","kind":"paper","name":"Improved survival with preoperative radiotherapy in resectable rectal cancer (Swedish Rectal Cancer Trial)","route":"/key-papers/paper-swedish-rectal-cancer-trial-preoperative-radiotherapy-nejm-1997/"},{"id":"paper-turrisi-twice-daily-thoracic-radiotherapy-limited-sclc-nejm-1999","kind":"paper","name":"Twice-daily compared with once-daily thoracic radiotherapy in limited small-cell lung cancer treated concurrently with cisplatin and etoposide","route":"/key-papers/paper-turrisi-twice-daily-thoracic-radiotherapy-limited-sclc-nejm-1999/"}]}}