I just checked the intial info I received from my surgeon. It was general info she gives to everyone and there was a flow diagram that clearly indicates that radiotherapy is part of the process for lumpectomy option and even sometimes (as was the case for me) after a mastectomy. BCNA are pretty clear with this in both their on-line info and the My Journey Kit too. I guess some people may not read this and you certainly don't take everything in when you are in appointments.
I think there is also a fair bit of info out there now that indicates that a local recurrence is more common after a lumpectomy than a mastectomy. I don't know what the statistics are but I am sure that doctors would be able to tell you if you asked. That is the thing, doctors will only give you stats if you ask because some people actually prefer not to know.
When it comes right down to it all we can do is encourage women to ask lots of questions and find out as much as possible before that initial surgery. I know some women have multiple surgeries to try and achieve clear margins too and sometimes wish they had just had a mastectomy to begin with. I think all we can do sometimes is offer support because this is one journey where things can change unfortunately. There are no crystal balls and we just have to choose the option that we feel comfortable with and realise that there are no guarantees with BC.