OBJECTIVETo clarify the clinicopathologic significance of the expression of the Bcl-2 protein (pBcl-2) and the Bax protein (pBax), and their clinical implications in Chinese and Japanese patients with human invasive ductal carcinomas (IDCs) of the pancreas.

METHODSThe study included 59 Chinese and 65 Japanese patients with IDCs of the pancreas. pBcl-2 and pBax expression were immuno-stained with streptavidin-biotin (SAB) method.

RESULTSpBcl-2 (+) was seen in 35.6% of Chinese and in 23.1% of Japanese patients. pBax (+) was seen in 49.2% of Chinese and 64.7% of Japanese patients. A comparison between them showed that there were significant differences in the male patients, in the patients with the moderately differentiated cancer, and in the elderly patients (chi squared = 4.447, P = 0.035; chi squared = 4.114, P = 0.043; chi squared = 6.657, P = 0.010 respective). In both Chinese and Japanese patients, those with pBcl-2 positive expression had a significantly higher survival rate than those with negative one (chi squared = 9.99, P = 0.0016; chi squared = 7.63, P = 0.0058). The group with pBax positive expression had a significantly higher survival rate in Japanese patients (chi squared = 9.37, P = 0.0022). Japanese patients whose tumors exhibited pBcl-2 and pBax positive immunostaining survived significantly longer than Chinese patients did (chi squared = 4.48, P = 0.0342; chi squared = 5.23, P = 0.023).

CONCLUSIONSThe expressions of both pBcl-2 and pBax are high found in Chinese and Japanese patients. The pBcl-2 positive expression implies a better prognosis in both Chinese and Japanese patients with IDCs of the pancreas. The effect of pBax expression on prognosis is different between Chinese and Japanese patients.