FLASH Radiotherapy (FLASH-RT)
FLASH-RT delivers the prescribed dose in milliseconds, opening a step-change in radiotherapy: protect healthy tissue while maintaining tumour control.
At a glance
FLASH-RT operates at ultra-high dose-rates (UHDR) and compresses delivery into sub-second timescales. This is why monitoring and control become mission-critical [4,5].
Dose-rate regime
Ultra-high
Commonly cited threshold: ≥ 40 Gy/s [4].
Delivery timescale
< 500 ms
Order-of-magnitude faster delivery than conventional workflows [4].
Clinical advantage
Normal tissue sparing
Demonstrated across multiple beam types [2,3].
The bottleneck
Beam monitoring
UHDR conditions stress conventional methods [4].
What is FLASH-RT
FLASH radiotherapy is an ultra-high dose-rate (UHDR) delivery regime that achieves treatment delivery in milliseconds. Since the work that reignited the field in 2014, FLASH-RT has become one of the fastest-moving areas in radiation oncology [1–3].
Why it is a breakthrough
FLASH-RT is designed to keep tumour control while substantially reducing toxicity to surrounding healthy tissue, enabling shorter, more comfortable treatments and a more efficient healthcare workflow [2–4].
FLASH vs CONV-RT — Treatment Delivery
Dose delivered dramatically faster, enabling a new treatment experience and workflow. [4]
Treatment experience
Benefits
FLASH-RT offers advantages for patients and for healthcare systems by reducing treatment burden and enabling more efficient delivery [2–4].
Minimised damage to surrounding healthy tissue
Normal tissue sparing is a central advantage of FLASH-RT [1–3].
Reduced risk of long-term side effects
Evidence supports reduced late toxicity in relevant studies [3].
Shorter, more comfortable treatment sessions
Delivery in milliseconds reduces time-on-couch and treatment friction [4].
Potential for improved quality of life
Reduced toxicity and simplified delivery support better patient experience [2,3].
Optimised equipment utilisation
Shorter treatments increase throughput and system efficiency.
Lower direct and indirect costs
Efficiency + fewer side effects can reduce cost burden.
Why beam monitoring is the key
At UHDR, monitoring becomes the gate to safe clinical scale. Conventional ionisation chambers saturate in this regime, making robust, real-time monitoring essential for control and safety [4].
Measure in real time
UHDR beams demand fast measurement of output and time structure for treatment control.
Guarantee reproducibility
Stable, traceable monitoring is fundamental to consistent outcomes and clinical adoption.
Enable translation
Monitoring is the enabling layer that turns breakthrough delivery into routine clinical practice.
References
- Favaudon V. et al., 2014. Science Translational Medicine. (FLASH effect)
- Vozenin M.-C. et al., 2022. Nature Reviews Clinical Oncology. (clinical translation)
- Wilson J.D. et al., 2020. Frontiers in Oncology. (overview)
- Romano F. et al., 2022. Medical Physics. (UHDR dosimetry & monitoring challenge)
- Gonçalves Jorge P. et al., 2025. Journal of Applied Clinical Medical Physics. (machine stability for clinical protocol)
FLASH-RT is the next performance leap in radiotherapy. RTBeamTech builds the monitoring layer that makes it controllable at scale.