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Patterns of lymph node metastasis in carcinoma of the distal bile duct.

BACKGROUND/AIMS
The aim of this study was to clarify the lymphatic spread in distal bile duct carcinoma in relation to local tumor extent (pT category).


METHODOLOGY
The distribution and number of involved nodes were examined in 42 patients with distal bile duct cancer.


RESULTS
Lymph node metastases were present in 25 of 42 patients (60%); 5 of 12 (42%) with pT2 tumors and 20 of 26 (77%) with pT3 tumors. Nodal involvement was not identified in 4 patients with pT1 tumors. The incidence of node positivity was higher in patients with pT3 tumors than in those with pT1 or pT2 tumors (p<0.01 or p<0.05). The total number of positive nodes was greater in patients with pT3 tumors than in those with pT2 tumors (mean: 3.08 vs. 0.75; p<0.01). All node-positive patients had involved nodes in the hepatoduodenal ligament or posterior pancreaticoduodenal region, or both. The number of positive nodes in the superior mesenteric and para-aortic region was greater in patients with pT3 tumors than in those with pT2 tumors (p<0.05).


CONCLUSIONS
As tumor invades the pancreas from the distal bile duct, lymphatic spread extends from the hepatoduodenal ligament or posterior pancreaticoduodenal region to the superior mesenteric and para-aortic nodes.