Relation between NGF expression and perineural invasion and pain in salivary adenoid cystic carcinoma

AIM: To observe the expression of NGF in salivary adenoid cystic carcinoma (ACC) and to evaluate the relationship between NGF and perineural invasion as well as pain in ACC. METHODS: Thirty two salivary ACC tissue samples were divided according to the presence of perineural invasion or pain and 5 normal parotid glands and 3 acinic cell carcinoma tissue samples were taken as control. NGF was examined by immunohistochemistry analysis. RESULTS: NGF was present in ductule cells of normal parotid glands but not in acinic cell carcinoma. 96.9% of the ACC showed positive, and cancer cells far from nerves presented weaker positive than those in perinural space. NGF expression in groups with perineural invasion or pain was significantly higher than that without perineural invasion or pain ( P 0.05). CONCLUSION: Enhanced expression of NGF may contribute to the perineural invasion and pain in salivary ACC.