Correlation between Angiogenesis and p53 Expression in Lung Adenocarcinoma of Young Patients

Lung cancer commonly occurs in individuals who are 60 years of age or older. Lung cancer in patients younger than 40 years of age is rare and is often advanced when discovered. However, the biological features of lung cancer in young adults have not yet been fully elucidated. This study was conducted to determine the role of p53 expression and neoangiogenesis in lung adenocarcinomas of young patients. Lung adenocarcinomas, which were surgically resected from 20 patients younger than 40 years of age between 1977 and 1996, were compared with lung adenocarcinomas selected with random sampling from 45 patients older than 60 years of age. The expression of p53, vascular endothelial growth factor (VEGF), CD34, a marker for vascular endothelial cells, and proliferating cell nuclear antigen (PCNA) were studied immunohistochemically in both young and elderly patient groups. Lung adenocarcinomas with p53-positive staining showed higher expression of VEGF protein than p53-negative tumors in both the young and the elderly groups. However, the intratumoral microvessel count was significantly higher in the p53-positive young group than in the elderly group. The percentage of VEGF-positive cells correlated significantly with intratumoral microvessel counts in the young group. The survival rate tended to be poorer in patients with a high VEGF labeling index and p53-positive staining than in other young patients. Lung adenocarcinoma occurring in young patients tends to have a poorer prognosis, and angiogenesis of lung adenocarcinoma in young patients is more closely correlated with p53 expression than in elderly patients.