My Mom Has Bilateral Breast Cancer- What's My Risk?

Hi Everyone,

This forum has been my lifeline since my mom's dx last May- although I rarely post, I've gotten the comfort of knowledge and seen how supportive everyone is. Of course, I wish there was no such thing as cancer and none of us had to be here at all! 

  Anyway, my 66 year old mom has Stage IV bilateral breast cancer- mets to multiple bones, lungs, nodes, and had bilateral malignant pleural effusions upon dx. She had a large tumor in right breast, much smaller in left. I don't know if it is ductal or lobular, which I know makes a difference since lobular carcinoma is more often bilateral. The bc is strongly ER+&PR+, HER-. I don't know the grade either- I go to all mom's appt's with her, but she relies on me for info and I'm afraid to ask the doctor too many questions for fear he will give an answer that scares or discourages her. She is doing great- on Femara & Zometa, completely asymptomatic. So she is very cheerful and optimistic and I don't want to ruin that by having her hear some statistic that may never apply to her. She probably had the cancer for a long time before dx- she had never had a mammogram so we have no idea. She also went through menopause very late- she was probably about 60. So she probably was premenopausal when she got breast cancer, although she was most likely older than 50 unless it was VERY slow moving. I see some stats that consider "younger age" premenopausal, and others before age 50. This difference concerns me because to my understanding, when a 1st degree relative has breast cancer at a younger age, the risk is higher to relatives.

  I don't know my father's family hx at all, and my grandmother & great grandmother and her sister (small family) lived til their 80's & 90's. My aunt, the only other female relative besides distant cousins, is alive & well at age 64. So my mom is the only relative I know to have breast cancer in our family. My grandmother was a lifelong smoker and died of lung cancer at age 80- doesn't really count as family hx. So basically, I'm wondering, am I at extremely high risk? I did that risk calculator and it has me at about 19% lifetime risk as opposed to about 10% regular population(not sure exactly)- not too bad. Then today I read that if a 1st degree relative has bilateral breast cancer, the risk is 5X higher. So that puts me at 45-50% chance of getting breast cancer if that is true! I've been thinking of a prophylactic mastectomy but know I need genetic counseling and my insurance might not cover it. 

  Does anyone have any information on the significance of a 1st degree relative with bilateral, ER+ PR+ breast cancer that first occurred premenopause at about age 55-60? It's time for my mammo- 6 month schedule due to complex cyst found in July. So I'm worrying more than usual, but this 45% statistic really scared me and although it sounds unlikely, I don't know enough to be sure. Thanks in advance for any help!