I am new to this site. Was diagnosed with Stage I invasive ductal carcinoma in August. I had a lumpectomy in September with intraoperative radiation. Nodes were negative and margins clear. Specimen was ER and PR positive so was put on Letrozole. Lasted 3 month.... Nausea 24/7.... Like morning sickness. Just felt tired all the time and had trouble sleeping. Went off it for a month and felt great, but my oncologist started me on aromasin. Too early to tell, but hoping for less severe side effects.