Increased HER2 gene copy number is associated with response to gefitinib therapy in epidermal growth factor receptor-positive non-small-cell lung cancer patients

Federico Cappuzzo, Marileila Varella-Garcia, Hisayuki Shigematsu, Irene Domenichini, Stefania Bartolini, Giovanni L. Ceresoli, Elisa Rossi, Vienna Ludovini, Vanesa Gregorc, Luca Toschi, Wilbur A. Franklin, Lucio Crino, Adi F. Gazdar, Paul A. Bunn, Fred R. Hirsch