Gefitinib, an inhibitor of EGFR tyrosine kinase, has been demonstrated to produce clinical responses in a small number of patients with advanced non-small-cell lung cancer. Prior reviews had indicated that women and patients with adenocarcinoma histology had a somewhat higher response rate. In this review of 3 consecutive phase II trials, other clinical features were sought that might predict treatment response. Multivariable analysis revealed the presence of bronchioalveolar features and being a never smoker were additional, independent predictors of response.