Although the authors stated that metastatic tumor cells in the sentinel LN did not leave via efferent LVs in their animal model, another research group argued that overexpression of vascular endothelial growth factor (VEGF)-C in the cell line allowed the tumor cells to metastasize to the downstream LN21, while overexpression of VEGF-A was reported to contribute to distant metastasis via the blood vessels of the sentinel LN rather than through lymphatic routes22. Here, VEGFA is linked to neoplasm.