Prognostic significance of HER-2/neu overexpression in stage I adenocarcinoma of lung.

Abstract

Even with early diagnosis and adequate resection, the 5-year survival rate for stage I lung cancer patients is around 60% to 70%. Overexpression of HER-2/neu protein is associated with poor prognosis in lung cancers. In this study, we evaluated the expression of HER-2/neu in cancer cells of lung and assessed their clinicopathologic and prognostic significance. From 1986 to 1995, clinical data on 42 consecutive patients who underwent complete surgical resection for stage I lung adenocarcinoma were collected. Expression of HER-2/neu in paraffin-embedded tumor samples was determined by immunohistochemistry and scored with a semiquantitative method. Twenty-one of 42 patients were positive for HER-2/neu overexpression in tumor. Compared with patients with low HER-2/neu expression, patients with HER-2/neu overexpression had a significantly higher incidence of early tumor recurrence (p = 0.014). Survival was also significantly better in patients without HER-2/neu overexpression than in those with HER-2/neu overexpression (p = 0.0047). By univariate analysis, HER-2/neu overexpression and poor cell differentiation are two important factors correlated with poor prognosis. Expression of HER-2/neu oncoprotein in stage I lung adenocarcinoma can predict the tumor's aggressiveness. Early tumor recurrence was frequently detected in patients with HER-2/neu overexpression. We recommend an individualized therapeutic strategy based on the level of HER-2/neu oncoprotein in the tumor cells.