Anti HER 2/ neu antibody is:

The determination of tumor HER-2/neu expression for all newly diagnosed patients with breast cancer is now recommended. It is used for prognostic purposes in node-negative patients to assist in the selection of adjuvant chemotherapy because response rates appear to be better with doxorubicin-based adjuvant chemotherapy in patients with tumors that overexpress HER-2/neu, and as baseline information in case the patient develops recurrent disease that may benefit from anti-HER-2/neu therapy (trastuzumab). Patients with tumors that overexpress HER-2/neu may benefit if trastuzumab is added to paclitaxel chemotherapy. Cardiotoxicity may develop if trastuzumab is delivered concurrently with doxorubicin-based chemotherapy. Ref: Schwaz's principle of surgery 9th edition, chapter 17.