EGFR and ductal breast carcinoma in situ: For example, mammosphere generation by ductal carcinoma in situ cells in vitro was suppressed by about 60% by Gefitinib (Farnie et al, 2007) [which inhibits EGFR but also inhibits multiple other kinases (Brehmer et al, 2005)] but there appears to be no evidence of suppression of tumuor generation or ability to render ERα-negative cells sensitive to TMX with this agent.