Prognostic impact of para-aortic lymph node micrometastasis in patients with regional node-positive biliary cancer
A Yonemori1, S Kondo, Y Matsuno
1Department of Surgical Oncology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Background:
The presence of para-aortic lymph node metastasis in biliary cancer has a negative impact on prognosis. The relevance of para-aortic lymph node micrometastasis is unknown.
Methods:
A total of 546 para-aortic lymph nodes from 49 patients with biliary cancer with positive regional nodes and negative para-aortic nodes were immunostained with epithelial marker CAM5.2 (specific for cytokeratins 7 and 8). Immunostained tumour foci were classified as micrometastases or isolated tumour cells (ITCs) according to their size (larger or smaller than 0.2 mm).
Results:
CAM5.2-positive occult carcinoma cells in para-aortic lymph nodes were detected in nine (18 per cent) of 49 patients and in 18 (3.3 per cent) of 546 para-aortic nodes. There was no difference in postoperative survival between patients with and without CAM5.2-positive para-aortic nodes (P = 0.978), but survival for five patients with micrometastases was significantly worse than that for four patients with only ITCs (P = 0.047).
Conclusion:
In patients with regional node-positive and para-aortic node-negative biliary cancer, and occult cancer cells in para-aortic lymph nodes, prognosis was significantly worse in those with micrometastases than in patients with only ITCs. An efficient method of intraoperative detection of para-aortic lymph node micrometastases larger than 0.2 mm is needed.
