[Sonographic diagnosis of biliary tumor]

Biliary tract is the most suitable for sonographic diagnosis. That is caused by the biliary structure composing of bile and ductal system. Therefore, sonographic diagnosis of biliary tumor also is not so difficult. Careful observation of total biliary wall is necessary for diagnosis of the resectable small tumor. On the other hand, sonographic detection of advanced large tumor is easy. In the case of large tumor, the diagnosis of benign or malignant also is easy, but that of originating organ is rather difficult. However, in the case of small nodule or papillary tumor of biliary system, the detection of that is fairly difficult and the diagnosis of benign or malignant is more difficult. In the case of obstructing jaundice also, the ascertain of the end of dilated biliary duct is easy, and the detection of the tumor is not so difficult, but the diagnosis of benign or malignant is difficult. Therefore if the small nodule or papillary tumor in the biliary system was detected by the sonographic diagnosis, the following decision should be taken, suitably and promptly, that is the selection of the next one or more out of following many diagnostic modalities. There are ERCP, PTC, PTCD, angiography, sonographic guided biopsy or puncture, or laparatomy and so on.