Prognostic Significance of Loss of PTEN Expression in Patients with Non-small Cell Lung Cancer

ObjectiveTo determine whether or not loss of phosphatase and tensin homologue deleted on chromosome 10(PTEN) expression is correlated with clinicopathologic parameters and prognosis. Immunohistochemical staining was used to determine the expression of PTEN in 20 cases of normal lung tissues and 102 cases with non-small cell lung cancer(NSCLC). All patients were followed up from 3 to 60 months.The loss incidence of PTEN expresssion in NSCLC was 46.1% (47/102) while PTEN expression in normal lung tissues was positive. The loss incidence of PTEN expression was correlated to degree of differentiation of cancer, metastasis(including lymph node), and clinical stages. Patients with PTEN loss expression showed significantly worse in 5 years survival rate (10.64% vs 38.18%) and median survival time (15months vs 40months) than those with PTEN positive expression. Difference in survival for 45 patients with negative PTEN staining and positive PTEN staining was significant by Log rank (χ 2=21.06,P0.0001). The result of multivariate Cox analysis showed that PTEN expression was significantly correlated with prognosis.[Conclusion]Loss of PTEN expression is concerned with carcinogenesis of NSCLC and is an independent poor prognostic factor.