Continued gefitinib treatment after disease stabilisation prolongs survival of Japanese patients with non-small-cell lung cancer: Okayama Lung Cancer Study Group experience.

BACKGROUND: This study aimed to investigate the survival outcome of patients with non-small-cell lung cancer (NSCLC) who had obtained disease stabilisation with gefitinib treatment and to clarify the effect of continued treatment with gefitinib on prognosis. PATIENTS AND METHODS: We reviewed the clinical records of 365 Japanese patients with NSCLC who received gefitinib (250 mg/day). RESULTS: Of 324 (89%) patients assessable for response, 147 (45%) obtained disease stabilisation and 71 (22%) patients achieved an objective response. Overall survival in patients obtaining disease stabilisation was significantly longer than in patients with progressive disease (median survival time 12.1 versus 4.4 months; P <0.0001). In patients obtaining disease stabilisation, those who continued gefitinib treatment until disease progression tended to have longer overall and progression-free survival compared with those discontinuing gefitinib treatment (1-year survival rate 52.1% versus 36.6%, P = 0.08; 1-year progression-free survival rate 31.8% versus 5.2%, P = 0.001). Multivariate analysis showed discontinuing gefitinib was an independent risk factor for progression-free survival (hazard ratio 1.66; 95% confidence interval 1.07-2.56; P = 0.022) but not for overall survival. CONCLUSIONS: Our findings indicate the importance of achieving disease stabilisation with gefitinib treatment and continued gefitinib treatment in Japanese patients with disease stabilisation, although further studies are required to confirm these findings.