SHH and metastatic malignant neoplasm in the lymph nodes: We did not find a direct relationship between Shh and lymph node involvement, possibly because of the small number of patients recruited or because Shh affects only the early stage of intratumoral lymphangiogenesis and not lymph node metastasis, which requires the collaborative activities of several systems, such as the epithelial-to-mesenchymal transition and matrix metalloproteinase systems.