[The pathogenesis of perineural tumor invasion--a computer reconstruction study on its relation with a lymphatic spread in human and experimental carcinomas of the bile duct].

The way in which tumors reach the perineural space of the nerves from adjacent tissues has been studied by a computer 3-D reconstruction of a bile duct wall invaded by a carcinoma, from the case histories of two patients with a bile duct carcinoma and from rabbits given a VX2 tumor that had been transplanted. It was found that while carcinomas readily grew along the perineural spaces in an axial direction these carcinomas also had, simultaneously, abundant connections with tumors growing outside, especially with lymphatic tumors. Thus it was likely that tumors reach the distant nerves mainly via this lymphatic connection, i.e., first forming satellite lymphogenous foci around the nerves and then, as a second step, breaking into the perineural space.