Asian ethnicity as a predictor of response in patients with non-small-cell lung cancer treated with gefitinib on an expanded access program.

BACKGROUND The primary objective of this retrospective study was to investigate the potential role of East Asian ethnicity or origin in predicting response to gefitinib in advanced-stage non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS A chart review was done of all patients treated with gefitinib at M. D. Anderson Cancer Center on the Expanded Access Program. RESULTS There were 223 patients with advanced-stage NSCLC who were enrolled. Of these, 182 received >or= 1 dose, and 160 were evaluable for response. The partial response rate was 8.8%, and the stable disease rate was 26.3%. Median time to progression was 2.5 months, and median survival was 6.8 months. The 1- and 2-year survival rates were 35.3% and 12.4%, respectively. Partial responses were seen in 7 of 12 patients (58.3%) of East Asian origin compared with 7 of 131 patients who were white (5.3%). This difference was statistically significant when controlling for histology, smoking status, hemoglobin, and diarrhea. Never smoking and diarrhea were also independent predictors of response. CONCLUSION For the first time, in a multivariate analysis, we observed a positive relationship between East Asian origin and response to gefitinib. These findings might help determine which patients will likely benefit from gefitinib.