Perineural invasion as a prognostic factor in head and neck squamous cell carcinoma: a systematic review and meta-analysis

Background: Squamous cell carcinoma (SCC) is the most common type of head and neck cancer, and head and neck squamous cell carcinoma (HNSCC) was proved to having a high prevalence of perineural invasion (PNI). Although some reports have revealed a relationship between PNI and the prognosis in HNSCC patients, the contribution of PNI to the prognosis remains unclear.Objectives: This study was aimed to comprehensively and quantitatively summarize...