femara for 2nd breast cancer patient

I had breast cancer in my right breast 7 yrs. ago, had a lumpectomy, &  had chemo. & radiation therapy for that.  I couldn't follow up with Temoxaphen because of negative receptors.  Cancer was found in my left breast now, so I had a bilateral mastectomy and no cancer cells were found other than in the new cancer site when pathology was done on the removed tissue and nodes.  this cancer had positive estrogen receptors. The diagnosis is good and was rated as a "0".  I am now taking Femara, but am hesitant due to the 1st cancer 7 yrs. ago.  I am nervous about taking any estrogen therapy.  What is your opinion?

[Cleveland Clinic]

Dear Char214:  Femara is an aromatase inhibitor, it works by blocking the enzyme that converts the body's androgen hormones into estrogen.  This type of treatment is one of the appropriate hormone (anti-estrogen) treatments of estrogen receptive breast cancer in post-menopausal women.

[frustratedrg]

Is it common for the cancers to be estrogen positive in one breast and estrogen negative in the other