Association between p53 overexpression, cell proliferation, tumor necrosis and extent of apoptosis in operated pancreatic adenocarcinoma.

In this study we investigated the immunohistochemical expression of the p53 protein in 44 ductal pancreatic adenocarcinomas and its relation to cell proliferation, apoptosis and necrosis, three factors affecting tumor growth. The results were evaluated against survival and other clinical parameters of the patients. p53-positivity was found in 18/44 (41%) of the tumors. A positive p53 status was significantly associated with a high extent of necrosis (> or = 10% of tumor tissue)(p = 0.04, Fisher's exact test), with a high immunohistochemical expression of PCNA (p = 0.04, Fisher's exact test) and with a high mitotic count (p = 0.05, two-tailed t test). No statistically significant association was found between p53-positivity and high or low extent of apoptosis as evaluated by in situ labeling of the 3'-ends of the DNA fragments (p = 0.34, Fisher's exact test). Patient survival was not associated with the p53 expression of the tumors or separately with tumor cell proliferation, apoptosis or necrosis. The results suggest that an altered p53 function, as reflected by p53 overexpression, affects tumor growth by promoting cell proliferation and necrosis, but does not show a significant association with the extent of apoptosis in operated pancreatic adenocarcinoma.