Radiotherapy 5 days or 3 weeks

following my surgery for grade 1 breast cancer I am offered radiotherapy treatment. I have to choose either a 5 days or 3 weeks treatment. I am unsure which one to choose as I am tempted with the 5 days one but worry it is a new procedure and not enough study has been made. Can it be trusted?

I had my radiotherapy last summer. I attended the Royal Marsden. The FAST FORWARD study shows that the 5 day regime is as effective at 5 years and as safe.  It means less trips to hospital which is less effort. I had my chemo and surgery during lockdown so this seemed a huge advantage. It all went smoothly and over relatively quickly. I did feel fatigued afterwards for several weeks, but no other side effects. 


My oncologist recommended the 15 sessions for me based on my age (50). Her reasoning was that the 5 session course was just as effective as the 15 but because the study is only 5 years old they only know how effective it is for 5 years, whereas because I’m 50 she preferred to look at the data for effectiveness after 15/20 years and she knew what that data was. She had no reason to doubt 5 being as effective, but with any professional (as evidenced by the pandemic) one professional’s reading of data may differ from another’s : there are no absolute rights or wrongs!

I hope this helps

AM xx

Hello, I’m starting my 5 days of radiotherapy next Monday.

It is standard procedure at my hospital, and my oncologist told me that current research indicates 5 days as effective as 15. I wasn’t given a choice of length of treatment, just the choice to consent or not. She also told me that there does happen to be additional research indicating efficacy but it has not yet been peer reviewed published. I am 66, had grade 3, with a sufficiently high Oncotype score …  and this is my second bout of cancer, so I just want whatever they offer. I have no doubt they want the most effective treatment for me, having just finished quite toxic chemo, and now being prescribed hormone treatment, Bisphosphonates and calcium/vitamin d supplements.

Hopes this helps a bit, perhaps you could discuss the merits of each length of treatment with your oncologist, as you’ve been given a choice. Wishing you all the best.