COMPARATIVE-STUDY OF P53 EXPRESSION IN PRIMARY INVASIVE DUCTAL CARCINOMA OF THE PANCREAS BETWEEN CHINESE AND JAPANESE

Previous studies reported different frequencies of p53 expression betw een Japanese and Americans or Europeans. The present study was designe d to clarify whether there is a significant difference in p53 expressi on and its clinical implications between Chinese and Japanese patients with primary invasive ductal carcinoma (IDC) of the pancreas, p53 exp ression was studied in 39 Chinese and 47 Japanese patients, and immuno staining with the SAB method was performed using anti-p53 monoclonal a ntibody (DO-1) in formalin-fixed and paraffin-embedded specimens. Clin ical data were analyzed according to the International Union Against C ancer classification. p53 expression was seen in 71.8% of Chinese and in 48.9% of Japanese patients with IDCs of the pancreas (p < 0.05). Th e Chinese patients were significantly younger than the Japanese ones ( p < 0.05), but there were no significant correlations between p53 immu noreactivity and age, gender, stage, and histopathological grade in se parate analyses of the Chinese and Japanese patients. A comparison bet ween them showed that in patients younger than 55 and 65 years old, th e incidence of p53 expression was markedly lower in Japanese than in C hinese (p < 0.05), In Japanese patients, those with a p53-positive pan creatic cancer had a significantly lower survival rate than those with a p53-negative tumor, but there was no correlation between p53 expres sion and the prognosis of Chinese patients. The frequency of p53 expre ssion in IDC of the pancreas is higher in Chinese than in Japanese pat ients, and the effect of p53 expression on prognosis is different betw een Chinese and Japanese patients.