P21(WAF1 CIP1MDA-6) EXPRESSION IN NON-SMALL-CELL LUNG-CANCER - RELATIONSHIP TO SURVIVAL/

In order to clarify critical events during bronchial carcinogenesis, a nd to evaluate a possible prognostic role for p21 immunohistochemical detection, we assessed the immunohistochemical expression of p21 prote in in 60 surgically resected non-small-cell lung cancers (NSCLCs) that had been investigated previously for their p53 protein status. We fou nd that p21 protein was expressed in both normal and neoplastic tissue . In normal tissue, p21 immunoreactivity was detectable in a low perce ntage of well-differentiated cells. We found immunostaining for p21 in 80% of the investigated neoplasms. In 73.3% of the neoplasms, p21 was considered to be overexpressed. No relationship was found between p21 overexpression and tumor stage or tumor-nodal-metastatic (TNM) status . The histologic grading was slightly correlated with the p21 status ( P = -0.51), with no significant differences noted between squamous car cinomas and adenocarcinomas. Survival percentage curves for our lung-c ancer patients, based on a comparison of different p21 expression leve ls and constructed through a Kaplan-Meier analysis, showed significant differences in mean (P < 0.001) and overall (P < 0.001) survival time between patients of different p21 status, suggesting a favorable prog nostic value of p21 immunostaining for NSCLC patients.