Association of p53 expression with proliferative activity and poor-prognosis in patients with squamous-cell lung...

Tumor tissue of 65 patients with squamous cell lung carcinoma was analyzed for p53 expression using immunohistochemistry (DO-1) and for proliferative activity using flow cytometry. Of the 65 cases, 17 cases (26%) showed positive staining for p53, whereas 48 cases (74%) showed no expression. The median survival time for patients with p53-negative tumors was 100 weeks and for patients with p53-positive tumors 30 weeks (rank-sum test, p=0.03; log-rank test, p=0.14). The median survival time for patients with high proliferative activity (proportion of SG(2)M-phase cells >22%) was one year and for patients with low proliferative activity (proportion of SG(2)M-phase cells less than or equal to 22%) over 6 years (rank-sum test, p=0.04; log-rank test, p=0.01). There exists a trend that p53-positive squamous cell lung carcinoma had a higher proportion of SG(2)M-phase cells than p53-negative tumors. Multivariate analysis found independent prognostic significance for proliferative activity and stage but not for p53.