Expression and clinical implications of bcl-2 in extrahepatic bile duct carcinoma: its relationship with biological features.

bcl-2 expression in 38 extrahepatic bile duct carcinomas was immunohistochemically investigated in order to clarify its clinical significance in this carcinoma. bcl-2 was expressed in 17 cases (44.7%), in which more than 10% of the carcinoma cells were positive for bcl-2. bcl-2 expression was more frequently absent in cases with advanced stages (p = 0.0642), lymph node metastasis (p = 0.0009), perineural invasion (p = 0.0647) and aberrant p53 expression (p = 0.0181). Furthermore, bcl-2 expression was inversely related to the incidence of apoptosis (p = 0.0002) and proliferating activity of the cells (p < 0.0001). These results suggest that bcl-2 plays a role in negatively regulating apoptosis and its loss can be significantly linked to the biological aggressiveness of this carcinoma.