Whereas trastuzumab has recently been approved for the treatment of metastatic gastric cancer in combination with cytotoxic agents (Bang et al., 2010), similar studies targeting overexpressed/amplified ERBB2 in NSCLC (Gatzemeier et al., 2004; Langer et al., 2004; Lara et al., 2004b; Zinner et al., 2004; Krug et al., 2005; Herbst et al., 2007) and prostate cancer (Morris et al., 2002; Lara et al., 2004a; Ziada et al., 2004) have reported modest or disappointing results. The gene discussed is ERBB2; the disease is prostate cancer.