Background/aims: We assessed the importance of blood vessel invasion (BVI) by cancer in the metastatic lymph nodes for the development of liver metastases in colorectal cancer.
Patients and methods: The presence of BVI in the primary growth and in the lymph nodes was reviewed in 384 specimens.
Results: In cases with and without BVI in the nodes, the incidence of liver metastases was 49% and 10%, respectively (p < 0.01). The highest incidence of liver metastases was observed in patients with BVI both in the primary tumor and in the metastatic nodes. The next to the highest incidence was observed when BVI was present not in the primary lesion but in the metastatic nodes. When considering the number of metastatic nodes, the incidence of liver metastases was high in cases with BVI in the nodes regardless of the number of metastatic nodes.
Conclusion: These data suggest that the BVI in the metastatic nodes is an important factor for the development of liver metastases.