Prognostic significance of tumor suppressor gene maspin in pulmonary adenocarcinoma

7162 Background Maspin is a unique member of the serine protease inhibitor family with tumor suppressive potential in breast and prostate cancer. Recent studies have shown that loss of maspin expression correlates with progression and metastasis of tumors and poor prognoses for patients with several types of cancers. Paradoxically, maspin expression has been reported in ovarian and pancreatic cancers. However, the presence of maspin expression in pulmonary cancers has not been evaluated. In this study, we evaluated maspin expression in pulmonary adenocarcinoma in relation to a number of clinicopathological features. MethodsMaspin expression was examined immunohistochemically in a series of 78 pulmonary adenocarcinomas. ResultsThirty-seven (47%) showed distinct maspin expression (maspin-positive group) and 41 (53%) did not (maspin-negative group). In the surrounding pulmonary tissues, alveolar epithelial cells lacked maspin expression, but maspin staining was usually present in bronchial basal cells and occasionally present in surface bronchial epithelial cells. Maspin expression was not associated significantly with most clinicopathological variables including sex, age, tumor size, primary tumor, lymph node metastasis, visceral pleural invasion, pulmonary metastasis, stage grouping and p53 expression. However, the maspin-positive group had a better 5-year survival rate (62%) than did the negative group (42%). The difference in the 5-year survival rate was more significant in stage II-IV patients (maspin-positive group, 53%; -negative group, 16%, p = 0.049). Conclusions Our data indicate that maspin has prognostic significance for pulmonary adenocarcinoma. A better understanding of the role of maspin in tumor suppression may be helpful for development of novel chemotherapies for patients with this deadly tumor. No significant financial relationships to disclose.