p53 alterations in non-small cell lung cancers correlate with metastatic involvement of hilar and mediastinal lymph nodes.

Alterations of p53 are one of the most common molecular changes found in all types of lung tumors, suggesting a crucial role for p53 in bronchial carcinogenesis. However, the prognostic significance of p53 abnormalities in lung cancer patients is still unclear. By using genetic and immunohistochemical methods we have found p53 alterations in 40 of 53 (75%) primary, resected non-small cell lung cancer. A strong association (P = 0.0015) was found between deletions on chromosome region 17p13.3 and p53 mutations suggesting that loss of the wild-type p53 allele might be necessary for tumorigenesis. Correlations to clinicopathological parameters showed that p53 alterations (structural aberration of the gene and/or nuclear accumulation of the protein) are significantly linked with metastatic involvement of hilar and mediastinal lymph nodes (P < 0.01). Since the latter are well established prognostic factors for non-small cell lung cancer, p53 aberrations may also be a predictor of tumor aggressiveness.