Never-smoking history predicts long-term survival in patients with non-small cell lung cancer with postoperative recurrence

Abstract

20047 Background: Factors affecting long-term survival after postoperative recurrence in non-small cell lung cancer (NSCLC) patients have not been fully understood. Furthermore, molecular features of them also have remained undetermined. The aim of this study was to identify these possible factors and to investigate their association with epidermal growth factor receptor (EGFR) mutation. Methods: Fifty-eight patients with postoperative recurrent NSCLC treated at Okayama University Hospital between January 1999 and December 2003 were retrospectively analyzed. We defined those surviving for 2 years or longer after postoperative recurrence as long-term survivors. Tumor samples for EGFR mutation analysis were available in 32 (55%) patients and were examined in exons 18 to 21 of EGFR using direct sequence method. Results: Demographics of 58 patients were as follows: median age 65 years (range, 33–85 years), male/female, 69%/31%; adenocarcinoma/others, 69%/31%; ever/never-smokers, 66%/34% and local/local and distant/distant recurrence; 29%/10%/61%. Median survival time and 1-year survival rate for 58 patients were 22.7 months and 79%, respectively, with a minimum follow-up time of 2 years. Half of 28 long-term survivors did not have any smoking history, whereas only 6 never-smokers were included in the remaining 30 patients who died within 2 years, indicating that never-smoking history is significantly associated with long-term survival (p=0.016). In multivariate analysis, never-smoking history was a significant predictive factor for long-term survival (Odds ratio 4.90, 95% confidence interval: 1.26–19.00, p=0.022). Among 32 patients analyzed for EGFR mutation, patients harboring EGFR mutation in ever-smokers and in never-smokers were 10% and 82%, respectively. Seven (47%) of 15 long-term survivors analyzed had EGFR mutation; however, only 4 (24%) of 17 patients who died within 2 years did (p = 0.169). Conclusions: Our data suggest that never-smoking history might have a favorable effect on long-term survival in postoperative recurrent NSCLC patients, and long-term survivors tend to have EGFR mutation. No significant financial relationships to disclose.