World Radiotherapy Awareness Day — 2026 Edition: History & Key Milestones

Every year on September 7, the global cancer care community observes World Radiotherapy Awareness Day (WRAD) — a campaign built around one simple message: radiotherapy saves lives, and millions of people who need it still can't access it.

What Is World Radiotherapy Awareness Day?

WRAD was co-founded by Sandra Turner, a radiation oncologist and clinical professor at the University of Sydney, and Katie Wakeham, a Clinical Oncology Consultant at Imperial College Healthcare NHS Trust in London. The idea was first proposed publicly in November 2024 during London Global Cancer Week, and after a planning phase in early 2025, WRAD officially launched on September 7, 2025.

The campaign's theme for its first three years (2025–2027) is “One Voice for Radiotherapy” — a call for the fragmented radiotherapy community (physicists, oncologists, therapists, engineers, patients, and advocates) to speak collectively about the value and the shortfall of radiation treatment worldwide.

In its first year alone, WRAD gathered support from more than 70 radiation oncology organizations across the globe, drew over 9,000 website visits from 109 countries, and was the subject of 48 registered awareness events and 51 media features. It's a young campaign — but it's growing fast, and for good reason: more than half of all cancer patients will need radiotherapy at some point in their treatment, yet access remains wildly uneven between (and within) countries.

Why September 7?

The date isn't arbitrary. On September 7, 1953, the first cancer patient was treated using a modern linear accelerator (linac) at Hammersmith Hospital in London. That single treatment marked the beginning of the linac era — the technology that still underpins the vast majority of radiotherapy delivered around the world today.

Organizers considered other dates (Marie Curie's birthday, the anniversary of the discovery of X-rays), but September 7 won out because it represented a turning point in treatment technology itself — a fitting anchor for a day that's as much about engineering progress as it is about patient care.

A Timeline Worth Knowing: How Radiotherapy Became What It Is Today

For the 2026 edition, we're tracing the engineering and scientific milestones that turned a laboratory discovery into one of the three pillars of modern cancer treatment. Dates and attributions below are drawn from peer-reviewed medical physics histories and institutional archives (full list at the end); where historical sources disagree, we've said so rather than picking one version for the sake of a clean story.

8 November 1895 — X-rays discovered
Wilhelm Conrad Röntgen, working at the University of Würzburg, observed that a Crookes tube shielded in black cardboard was still causing a nearby platinobarium screen to fluoresce. He announced the discovery of a new, penetrating form of radiation in December 1895, calling it “X-radiation” because its nature was unknown. He received the first Nobel Prize in Physics for the work in 1901.

1896 — The first attempts at using X-rays therapeutically
Within weeks of Röntgen's announcement, several physicians on both sides of the Atlantic began experimenting with X-rays against tumors. Chicago medical student Emil Grubbe is often credited with treating a recurrent breast carcinoma on 29 January 1896 — but this claim rests entirely on an account Grubbe himself published 37 years later, with no surviving contemporary record, and is treated as disputed by medical historians. Better-documented 1896 cases include Victor Despeignes in Lyon (gastric cancer) and Leopold Freund in Vienna. The honest summary: radiotherapy's exact “first patient” is unresolved, but therapeutic use began within months of the discovery of X-rays itself.

1898 — Radium isolated
Marie and Pierre Curie isolated radium and polonium from pitchblende ore. Radium's steady gamma emission, without needing an external power source, made it the basis of early brachytherapy — needles and applicators placed directly in or against tumors — for the next several decades.

Early 1900s — The dosing problem
There was no standardized way to measure or prescribe radiation dose. Radiologists and early patients suffered severe, cumulative radiation injuries (Thomas Edison's assistant Clarence Dally is a well-documented case). This drove the first formal push toward dosimetry. The “roentgen” was adopted as a unit of radiation exposure in 1928, and the International Commission on Radiation Units and Measurements (ICRU) was established in 1925 — the direct ancestors of the dose-measurement standards biomedical/medical physicists still work to today.

1913 — The Coolidge tube
William Coolidge (General Electric) developed a hot-cathode, high-vacuum X-ray tube with independently controllable voltage and filament current. This was the key engineering step that made X-ray output stable and reproducible rather than dependent on a gradually degrading gas-discharge tube — a prerequisite for any therapy delivered in a measured, repeatable dose.

1920s–1930s — Orthovoltage therapy and fractionation
“Deep therapy” / orthovoltage X-ray units (roughly 150–280 kV) became the clinical standard. Their limited penetration meant they were effective mainly for superficial tumors and caused significant skin toxicity at depth. In parallel, radiobiology work in this period (including at the Curie Institute) established fractionation — splitting a total dose across multiple sessions — as a way to damage tumor tissue while allowing healthy tissue more time to recover. Fractionation remains a foundational principle of radiotherapy prescribing today.

27 October 1951 — First cobalt-60 teletherapy treatment
Canadian medical physicist Harold E. Johns, having recognized cobalt-60's potential as a cheaper, more practical alternative to radium, led the design of a cobalt-60 unit. The first clinical treatment (a cervical cancer patient) was delivered at Victoria Hospital in London, Ontario, on 27 October 1951, using a unit built with Atomic Energy of Canada Limited and the National Research Council; a second prototype from Johns' own Saskatchewan group treated its first patient shortly after, on 11 November 1951. Cobalt-60 units — simpler and far cheaper to build and maintain than a linear accelerator, since they need no electron gun or waveguide, just a shielded radioactive source — went on to dominate the market through the 1950s–60s (over 1,120 units sold globally between 1951–61, versus roughly 136 megavoltage X-ray units sold across the entire 1939–69 period). Cobalt-60 machines remain in clinical use today, particularly in lower-resource settings, precisely because of that cost and robustness advantage.

1953 — First patient treated on a dedicated medical linear accelerator
An 8 MV linear accelerator built by Metropolitan-Vickers was installed at Hammersmith Hospital, London, in 1952 and treated its first patient in 1953 — the milestone World Radiotherapy Awareness Day commemorates every September 7. It's worth noting for accuracy: published histories don't fully agree on the exact date. The definitive peer-reviewed history of the clinical linac (Thwaites & Tuohy, Physics in Medicine and Biology, 2006) states patient treatment began “on 7 September” 1953; some AAPM historical materials instead cite 19 August 1953. WRAD's own campaign explicitly ties its date to the Thwaites & Tuohy account. Either way, the underlying engineering lineage is well established: medical linacs descended from wartime radar magnetron/klystron technology, with the first experimental linac (0.5 MeV) built by D.W. Fry's group at Harwell, UK, in late 1946, and a separate 1.7–4 MeV unit built at Stanford/Varian Associates in 1947.

1971 — Clinical CT scanning introduced
Godfrey Hounsfield's CT scanner (EMI, UK) gave clinicians the first practical way to see a tumor's true three-dimensional shape and position before treatment. Through the late 1970s and 1980s, CT data combined with computerized treatment-planning systems and motorized multileaf collimators (MLCs) made 3D conformal radiotherapy (3D-CRT) — shaping the beam to the tumor's actual geometry — clinically practical.

1990s — Intensity-modulated radiotherapy (IMRT)
Dynamic MLCs and inverse treatment-planning algorithms (the planning software works backward from a desired dose distribution to the beam pattern needed to produce it) enabled IMRT, clinically adopted at a number of centers including Memorial Sloan Kettering and William Beaumont Hospital during the decade. IMRT allowed sharper dose gradients — high dose to the tumor, a fast drop-off into adjacent healthy tissue — which mattered most for tumors near sensitive structures (head and neck, prostate).

Early 2000s — Image-guided radiotherapy (IGRT)
On-board kilovoltage and megavoltage imaging, and later cone-beam CT, were integrated directly into linear accelerators, allowing daily verification (and correction) of patient and tumor position immediately before each treatment. The same period saw proton therapy move from research use — the first proton patient was treated at Lawrence Berkeley Laboratory in 1954 — into hospital-based clinical practice, with Loma Linda University Medical Center opening the first hospital-based proton center in 1990.

2010s–present — Adaptive planning and MR-guided treatment
MRI-linac systems (clinically introduced around 2018, e.g. Elekta Unity, ViewRay MRIdian) combine real-time MRI with beam delivery, letting a plan be adjusted for anatomy that has genuinely changed since the last session rather than relying on daily imaging alone. Machine learning tools for automated organ/tumor contouring are increasingly built into commercial planning software, though the extent of autonomous (versus clinician-reviewed) use varies significantly by center and regulatory jurisdiction.

7 September 2025 — World Radiotherapy Awareness Day launches
Seventy-plus years after that first linac treatment, the global radiotherapy community formally organized around a shared advocacy campaign for the first time — not around a new machine, but around the argument that access to the machines already invented remains the unsolved problem.

Why This History Matters for Biomedical Engineering

Nearly every advance above was an engineering problem before it was a clinical one: generating a controllable beam, shaping it, measuring dose precisely, imaging a moving target, and eventually automating planning without sacrificing safety review. It's also a genuinely mixed history from an adoption standpoint — cobalt-60, the simpler and cheaper technology, outcompeted the linac commercially for over a decade despite the linac's technical advantages, a useful reminder that cost, serviceability, and infrastructure requirements often decide what actually gets deployed, not raw technical superiority.

That's directly relevant to the access gap WRAD highlights. A modern linac needs stable, high-quality power, a shielded vault, and locally available physicists and biomedical/clinical engineers for commissioning, calibration, and ongoing quality assurance — not just capital to purchase the machine. In many lower-resource settings, cobalt-60 units remain in use today for exactly the reasons they won the market in the 1950s: they tolerate less reliable infrastructure and require less specialized upkeep than a linac. The access problem WRAD is organized around is, in large part, still an engineering and workforce-infrastructure problem, not only a funding one.

How to Mark the Day

• Visit worldradiotherapy.org to see this year's campaign resources and toolkit
• Share the “One Voice for Radiotherapy” message on social media
• If you work in a radiotherapy department, clinic, or engineering team, consider registering a small internal event or discussion
• Revisit this page each September — we'll publish a new edition every year tracing a different angle on radiotherapy's past, present, and future

Looking Forward

From a single accidental discovery in 1895 to a linac treating a patient in 1953, to AI-guided adaptive treatment plans today, radiotherapy's history is really the history of engineers and physicians solving one problem at a time. World Radiotherapy Awareness Day asks us to remember that history — and to make sure the next chapter includes everyone who needs it, not just those who happen to live near a machine.

This is gobioeng.com's 2026 edition of our annual World Radiotherapy Awareness Day series. Check back next September for the 2027 edition.

Sources & Further Reading

• Thwaites, D.I. & Tuohy, J.B., “Back to the future: the history and development of the clinical linear accelerator,” Physics in Medicine and Biology, 2006
• AAPM Virtual Museum, “External Beam Radiotherapy” exhibit (museum.aapm.org)
• Canadian Medical Hall of Fame, entry on Harold Johns
• ASTROnews, “Giants in Radiation Oncology: Harold Johns”
• A Retrospective of Cobalt-60 Radiation Therapy, AAPM proceedings
• World Radiotherapy Awareness Day official campaign materials (worldradiotherapy.org)
• The ASCO Post, “The X-Ray Era” (June 2018)