preventative bilateral mastectomy?

i have been told by doc my breast history puts me in a high risk group for getting cancer.grandmother had breast cancer,have dense breast tissue,fibrocystic disease,two benign lumps removed,diagnosed w atypical ductal hyperplasia and the adh tissue was removed.doc tells me to seriously consider preventative bilateral mastectomy .is that crazy?

[Cleveland Clinic]

Dear brettus:  There is much to be considered in terms of choosing preventive bilateral mastectomy.  One of the biggest factors is risk.  Though you list some risk factors, bilateral mastectomy is a big step and generally recommended for women at extremely high risk.  For example, your grandmother may or may not increase your risk (depending on the age she was diagnosed).  Family history is generally most relevant for first degree relatives (mother, sister, daughter).  The most common risk leading to prophylactic mastectomy is having the BRCA1 or BRCA2 gene.  We would strongly recommend that you have a discussion with a genetic counselor who can outline your risk so that you can make a completely informed decision.