Sympathetic innervation contributes to perineural invasion of salivary adenoid cystic carcinoma via the β2-adrenergic receptor

Purpose Perineural invasion (PNI) is reported to correlate with local recurrence and poor prognosis of salivary adenoid cystic carcinoma (SACC). However, the pathogenesis of PNI remains unclear. The aims of this study were to investigate the correlation between sympathetic innervation and SACC PNI and to elucidate how the sympathetic neurotransmitter norepinephrine (NE) regulates the PNI process.