Preoperative gefitinib versus gefitinib and anastrozole in postmenopausal patients with oestrogen-receptor positive and epidermal-growth-factor-receptor-positive primary breast cancer: a double-blind placebo-controlled phase II randomised trial.

Background: Some oestrogen-receptor (ER) positive breast cancers express epidermal growth factor receptor (EGFR), but whether inhibition of EGFR can suppress proliferation of breast cancer cells and ER function is not known.

Methods: In a double-blind, placebo-controlled randomised trial of 56 postmenopausal patients with ER-positive and EGFR-positive primary breast cancer, 27 women were randomly assigned to the tyrosine-kinase inhibitor of EGFR gefitinib (250 mg given orally once a day) and the aromatase inhibitor anastrozole (1 mg given orally once a day), and 29 women to gefitinib (250 mg given orally once a day) and placebo of identical appearance to anastrozole given orally once a day, all given for 4-6 weeks before surgery. Primary outcome was inhibition of tumour-cell proliferation, as measured by Ki67 antigen labelling index.