Indicationaromasin is a prescription medicine for: early breast cancer: aromasin is indicated for the adjuvant treatment (additional treatment given after the primary or main treatment) of postmenopausal women with estrogen-receptor positive (er positive) early breast cancer. treatment with aromasin should begin 2 to 3 years after tamoxifen, at which time tamoxifen should be stopped. treatment with aromasin should continue for 2 to 3 years until a total of 5 years of adjuvant treatment of tamoxifen and aromasin have been completed. advanced breast cancer: aromasin is indicated for the treatment of advanced breast cancer in postmenopausal women whose disease has progressed after tamoxifen therapy.dose: one 25 mg tablet once daily after a meal