Chest wall radiotherapy? I can’t decide!

Hi lovely ladies! 🌸🌸

I’m one month out from right mastectomy and oestrogen blocker (letrozole) tablet (HR+ HER2-)  I’m having radiotherapy in the armpit and above collar bone in the coming few weeks due to positive sentinel lymph node. I’m torn whether to have chest wall radiotherapy or not! My surgeon thinks the 1.1mm clear margin on the lateral aspect of the tumour removed with the breast is too tight for my invasive lobular type cancer. My radiation oncologist thinks the margin is ok, and that the latest big study shows that chest wall radiotherapy vs. no chest wall radiotherapy makes a negligible difference on recurrence rate in similar cases to mine. Help, I’m looking at the pros and cons and just can’t decide!