# FAST-Forward

Source: https://onco.cc/trials/fast-forward/  
OnCo record `fast-forward` (Trial). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

FAST-Forward cut breast radiotherapy to five treatments in a single week and showed the same low relapse rate as the three-week standard, with similar late effects at five years.

## Summary

FAST-Forward randomised 4,096 women with early breast cancer to 40 Gy in 15 fractions, 27 Gy in five or 26 Gy in five fractions over one week. Five-year ipsilateral breast tumour relapse was 2.1 percent after 40 Gy and 1.4 percent after 26 Gy, meeting the non-inferiority margin; late normal-tissue effects after 26 Gy were similar to the standard arm while 27 Gy gave more (Murray Brunt and colleagues, Lancet 2020). One-week radiotherapy became standard in the UK and, accelerated by the pandemic, widely elsewhere.

## Fields

- Kind: Trial
- Status: positive
- Last checked: 2026-09-16
- Tags: radiation-wave2
- Phase: 3
- Setting: Early breast cancer after surgery: 26 Gy in five fractions over one week versus 40 Gy in 15 fractions over three weeks
- Sponsor: Institute of Cancer Research (UK)
- Enrolled: 4096
- Result: 5-year ipsilateral breast tumour relapse 1.4% (26 Gy in 5) vs 2.1% (40 Gy in 15), non-inferior.
- Outcomes: Ipsilateral breast tumour relapse at 5 years: 26 Gy in 5 fractions 1.4% vs 40 Gy in 15 fractions 2.1%

## Sources

- ISRCTN19906132: https://www.isrctn.com/ISRCTN19906132
- Lancet 2020: https://doi.org/10.1016/S0140-6736(20)30932-6

## Connected records

- cancers: [HER2-positive breast cancer](https://onco.cc/cancers/breast-her2-positive/), [HR-positive / HER2-negative breast cancer](https://onco.cc/cancers/breast-hr-positive/), [Triple-negative breast cancer (TNBC)](https://onco.cc/cancers/tnbc/)
- technologies: [Hypofractionated radiotherapy](https://onco.cc/technologies/hypofractionated-radiotherapy/), [IMRT / IGRT (modern external beam)](https://onco.cc/technologies/imrt-igrt/)
- terms: [Hypofractionation (fewer, larger radiotherapy doses)](https://onco.cc/terms/hypofractionation/)

---
JSON: https://onco.cc/api/v1/entities/fast-forward.json