The purpose of this study was to investigate the possible association between expression of survivin, pathological findings in the tumor and survival in patients with small adenocarcinoma of the lung. Seventy-nine patients with resected tumors <2 cm in diameter were entered into the study. There were 33 males and 46 females, with a median age of 64 years (range 26-83 years). The pathological stage of the tumors was recorded as stage I, II, III and IV in 72, one, five and one case, respectively. Each patient underwent curative surgical resection for lung cancer between July 1992 and November 1999. The resected tumors were subjected to immunostaining for survivin. Thirty-eight patients had tumors with < or = 10% survivin-positive cells and 41 patients had tumors with >10% survivin-positive cells. When survivin expression and pathological findings in the resected tumors were analyzed, the frequency of venous invasion was significantly higher in the survivin-positive group (36.6% vs. 13.2%; p=0.0167). In contrast, the overall survival of survivin-positive patients (n=41) was significantly worse than that of individuals whose tumors were negative for survivin expression (n=38; log-rank test, p=0.014; Wilcoxon test, p=0.021). It can be concluded that the expression of survivin in tumor cells is a factor of poor prognosis in patients with small adenocarcinoma of the lung.