Clinical importance of correlations between p53 immunoreactivity and clinicopathological parameters in lung carcinoma

Many studies have revealed the frequency of p53 abnormalities in lung cancer. However, clinico-pathological studies of p53 abnormalities have yielded conflicting results. We examined the p53 immunoreactivity and studied the correlations of p53 status and clinicopathological parameters in 76 primary lung cancers. By using DO-7 antibody, different degrees of p53 immunoreactivity was detected in 8 of 30 small cell lung cancer (SCLC, 26.6%) and 22 of 46 non-small cell lung cancer (NSCLC, 47.8%), 6 of 19 adenocarcinoma, 16 of 27 epidermoid carcinoma cases. In the whole group, no correlation was detected between the p53 status and the histological types of tumor, local tumor invasion, nodal status, and distant metastasis and patient characteristics, such as age, gender or smoking habit. P53 status was also found to have no effect on survival. However, in the NSCLC group, there was a significantly higher p53 immunoreactivity in well- and moderately-differentiated tumors (p<0.05). Patients with p53 immunoreactivity had a poor therapeutic response in the whole group. We concluded that, although p53 immunreactivity may be found in NSCLC, this does not correlate with clinicopathological parameters except therapeutic response. In SCLC p53 immunreactivity can be negligible.