PURPOSE Based on 5-year or shorter-term follow-up data in recent randomized trials, adjuvant cisplatin-based chemotherapy is now generally recommended after complete surgical resection for patients with non-small-cell lung cancer (NSCLC). We evaluated the results of the International Adjuvant Lung Cancer Trial study with three additional years of follow-up. PATIENTS AND METHODS Patients with completely resected NSCLC were randomly assigned to three or four cycles of cisplatin-based chemotherapy or to observation. Cox models were used to evaluate treatment effect according to follow-up duration. Results The trial included 1,867 patients with a median follow-up of 7. 5 years. Results showed a beneficial effect of adjuvant chemotherapy on overall survival (hazard ratio [HR], 0. 91; 95% CI, 0. 81 to 1. 02; P = . 10) and on disease-free survival (HR, 0. 88; 95% CI, 0. 78 to 0. 98; P = . 02). However, there was a significant difference between the results of overall survival before and after 5 years of follow-up (HR, 0. 86; 95% CI, 0. 76 to 0. 97; P = . 01 v HR, 1. 45; 95% CI, 1. 02 to 2. 07; P = . 04) with P = . 006 for interaction. Similar results were observed for disease-free survival. The analysis of non-lung cancer deaths for the whole period showed an HR of 1. 34 (95% CI, 0 VSports手机版. 99 to 1. 81; P = . 06). CONCLUSION These results confirm the significant efficacy of adjuvant chemotherapy at 5 years. The difference in results beyond 5 years of follow-up underscores the need for the long-term follow-up of other adjuvant lung cancer trials and for a better identification of patients deriving long-term benefit from adjuvant chemotherapy. .