Preoperative therapy with trastuzumab and oral vinorelbine (± endocrine therapy) in patients with HER2-positive breast cancer

BACKGROUND: Combined trastuzumab and intravenous vinorelbine yielded high clinical activity as preoperative treatment in patients (pts) with HER 2/neu positive breast cancer. PATIENTS AND METHODS: We tested a preoperative combination of trastuzumab with oral vinorelbine (oV) in pts with locally advanced (T2-T4 N0-3 M0) HER2-positive breast cancer. Trastuzumab was administered i.v q 3 wks and oV was administered at the dose of 55 mg/sqm on days 1 and 3 q 3 wks, for 8 courses. Pts with ER > or = 10% tumors received endocrine therapy with letrozole 2.5 mg/day, plus monthly triptorelin if premenopausal. RESULTS: Forty-five pts entered the study. The overall response rate (CR + PR) was 76% (95% CI: 60%-87%). pCR was observed in 4 pts (10%). Among ER-positive tumors 21/25 pts obtained a clinical response (84%) and two pts obtained a pCR (8%). CONCLUSIONS: The combination of trastuzumab and oral vinorelbine demonstrated encouraging activity in patients with HER 2 positive ER-positive tumors. Alternative strategies should be investigated in patients with endocrine non responsive disease.