Abstract
Pathologic study of 106 resected specimens bile duct carcinoma was performed. In 87 specimens carcinoma invaded beyond the bile duct wall, while in 19 specimens carcinoma was limited within the bile duct wall. In those cases where carcinoma invasion was limited to the bile duct wall but extended to outer fibroelastic layer, incidence of lymph node metastases and neural invasion was higher than that of carcinoma limited to inner fibroelastic layer. Extended surgery should be considered in cases with cancer invasion to outer fibroelastic layer in order to improve postoperative survival.
The problem of surgical treatment of bile duct carcinoma is intraductal tumor seeding which causes recurrence. Microscopic study disclosed that resection should be performed more than 2 cm distant from the main tumor to be surgical stump free from cancer cell. In 24 cases (23%) longitudinal intraductal spread of carcinoma was verified in the duct epithelium, but in 88cases (77%) tumor extended beneath the duct epithelium through bile duct wall of periductal tissue. This result indicated that it would be difficult to determine intraductal tumor spread with intraoperative macroscopic findings.
The modes of the lateral spread of cancer cells were analyzed into three types; i.e.direct invasion, (37%), vascular invasion (32%) and neural invasion (31%).
