A phase II trial with trastuzumab (Herceptin, Genentech, Inc., South San Francisco, CA, USA), a humanised anti-Her2 monoclonal antibody, which has been used to successfully treat Her2-overexpressing breast cancer, reported a low (7%) partial response rate with only a 2-month progression-free interval in recurrent ovarian cancers overexpressing Her2 (Bookman et al, 2003). Here, ERBB2 is linked to breast cancer.