1 patient with A763_Y764insFQEA was treated with erlotinib in combination with chemotherapy and had partial response; 1 patient with V774_C775insHV was treated with a combination of chemotherapy and gefitinib with partial response followed by 1 year of erlotinib maintenance prior to disease progression, at which time he was switched to neratinib without benefit; 2 patients with D770_N771insGT and V774_C775insHV were treated with erlotinib as single agent with no response.