HER-2 expression in local advanced breast cancer and the efficacy of neoadjuvant chemotherapy regimens

OBJECTIVE: To investigate the relationship between HER-2 expression and the efficacy of neoadjuvant chemotherapy in local advanced breast cancer. METHODS: Different neoadjuvant chemotherapy regimens, namely CMF, CEF, and NEF, were administered in 132 patients with local advanced breast cancer for 2 cycles, each lasting for 28 days. According to the criteria recommended by WHO, the efficacy and safety of the regimens were evaluated after two cycles of neoadjuvant chemotherapy. HER-2 expression was examined by immunohistochemistry using specific monoclonal antibodies before chemotherapy and after surgery. RESULTS: The overall response rate (RR) of CMF, CEF, and NEF regimens were 39.5% (17/43), 54.3% (25/46) and 72.1% (31/43), with incidence of leukopenia of 34.9% (15/43), 58.7% (27/46) and 60.5% (26/43), respectively. Other adverse effects including decreased hemoglobin (Hb) level, thrombocytopenia, gastrointestinal irritation and alopecia were similar between the 3 groups (P>0.05). No significant variation in HER-2 expression occurred after administration of the 3 regimens. The overall RR to CMF regimen in HER-2-negative breast cancer patients was significantly higher than that in HER-2-positive patients, but showed no significant difference with CEF and NEF regimens. CONCLUSION: HER-2 expression is not decreased after neoadjuvant chemotherapy in breast cancer patients, and HER-2-positive breast cancer can be resistant to CMF regimen, but not to CEF and NEF regimens.