Timescale for radiotherapy after operation

Hi,

My aunt had her lumpectomy operation 5 and a half months ago. She was advised to have radio. However, she was uncertain initially and time flew. Now, she’s getting split opinions from 2 doctors - one advised that she should still do it, while the other claimed since she is fine, she probably doesn’t need it.

Has anyone been in a similar situation? Please advise. Thank you.

Gracey.