Whilst you wait for the other forum user to reply with their knowledge and experiences you might find it uesful to read the BCC booklet 'breast cancer in families'. It explains what is meant by a significant family history of breast cancer and suggests what to do if you think this may apply to you or to members of your family. Just click on the link if you would like to order a copy or read this on line:-
I hope you find it helfpul.
Kind regards Sam, BCC Facilitator