Have the 10-year results from UK FAST-Forward impacted your practice with regard to patient selection?

I would consider our practice at Mayo as early adopters of ultra-hypofractionation for breast, largely driven by similar institutional trials for shorter courses and the patients we care for. As a result, we have pretty routinely offered 26 Gy/5 fraction whole breast RT since the 5-year follow-up was published, with the caveats that the follow-up was shorter and that there could be small differences at long-term follow-up that were not yet apparent in the publication. (As an aside -- We also have offered 5 fx 26 Gy dose for mini-tangent partial breast RT, extrapolating from IMPORT LOW mini-tangent 40 Gy approach. I use the Florence 5 fraction 30 Gy IMRT or multi-field for PBI as well when I think the patient should have 30 Gy over 26 Gy -- ...

For us, for most node negative patients, the standard is 5 fractions (APBI or whole breast based on technical or tumor factor); if they need boost after whole breast we use 10 Gy in 4 fractions.

Have not done 5 fractions for those who need concurrent systemic treatment and use 40 in 15 with boost. Many of these also need RNI.