BACKGROUND: In agreement with other reported studies, wehad previously found a possible association between gender and prognosis in stage I non-small cell lung cancer (NSCLC), showing a higher survival rate among females. OBJECTIVES: The purpose of this study was to further clarify the role of gender as a possible prognostic factor in NSCLC. METHOD: In a retrospective cohort study, we examined the survival of 163 NSCLC patients who underwent curative surgical treatment at the Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS) Hospital between 1990 and 1997. Data was analyzed using Kaplan-Meier plots. Additionally, we used the Mann-Whitney test for comparing group survival rates and the Cox regression model to adjust for potential confounding factors. RESULTS: Were included 124 (76.07%) males and 39 (23.93%) females, whose median survival was of 32.3 and 60.6 months, respectively. The 5-year survival was 38.0% for men and 55.4% for women (P=0.030). Considering only stage I patients, survival rates were 44.4% and 81.8% for men and women, respectively (P=0.009). Effect of gender continued after adjustment for several factors (age, hemoglobin, histology, tumor size, type of surgery and postoperative complications). CONCLUSION: This study confirms our previous findings that women live longer after NSCLC surgery when compared to men. This result is only observed at an early stage and persists after adjustment of several factorsP

Keywords: Carcinoma, bronchogenic [surgery]; Carcinoma, bronchogenic [epidemiolgy]; Prognosis; Sex distribution; Disease - free survival.