The Likely Sites of Nodal Metastasis Differs According to the Tumor Extent in Distal Bile Duct Cancer

Background: In the revised Japanese and Worldwide TNM classification of distal bile duct cancer, the lymph node status is defined as N0 or N1 without reference to the tumor location or extent, according to the presence/absence of metastasis to the regional lymph nodes.

Methods: Data of 94 patients with distal bile duct cancer who had undergone pancreaticoduodenectomy were reviewed retrospectively. In formalin-fixed specimens, we measured the longitudinal lengths from the papilla to the lower and upper margins of the tumor, in order to investigate the correlation of the tumor extent with the likely sites of nodal metastasis.

Results: The frequencies of metastasis to the posterior pancreaticoduodenal nodes (7.1 %) and superior mesenteric artery nodes (0.0 %) were significantly lower in the cases in which the length from the papilla to the lower margin of the tumor was ≥30 mm. The frequencies of nodal metastasis to the common hepatic artery nodes (0.0 %) and hepatoduodenal ligament nodes (6.7 %) were significantly lower in the cases in which the length from the papilla to the upper margin was <40 mm.

Conclusion: The likely sites of nodal metastasis differ according to the extent of the tumor in cases of bile duct cancer.