Prognostic and clinicopathological significance of podoplanin immunoexpression in oral and oropharyngeal squamous cell carcinoma: a systematic review.

BACKGROUND: Podoplanin (PDPN) is a glycoprotein associated with epithelial-mesenchymal transition, invasion, and metastasis in several types of malignancies, including oral and oropharyngeal squamous cell carcinoma (OSCC). The aim of this systematic review (SR) was to summarize and critically appraise the available evidence about the association between PDPN immunoexpression and clinicopathological features and its utility as a prognostic marker in OSCC. METHODS: Five electronic databases and three grey literature databases were searched for immunohistochemical studies, which were selected in a two-phase process. RESULTS: From 721 records identified, 22 cohort and seven analytical cross-sectional studies were included. Few studies reported that PDPN expression was associated with poorer survival rates in OSCC: overall survival = 4/12, disease-free survival = 4/7, cancer-specific survival = 2/4 studies. Positive associations were mostly reported on lymph node involvement, higher histopathological grade, and advanced clinical stages. CONCLUSION: Within limitations of this SR, PDPN may be associated with lymph node involvement, histopathological grade, and clinical stage of OSCC. Current evidence suggests that PDPN could be a useful prognostic marker for OSCC that needs further exploration.