Background: It was recently suggested that the upregulation of podoplanin (PDPN) in cancer cells plays a significant role in tumor invasion and metastasis and that it is significantly associated with poor prognosis in oral, cutaneous, and esophageal squamous cell carcinoma. The aim of this study was to investigate the expression pattern of PDPN in sinonasal squamous cell carcinoma (SNSCC) and to evaluate its role as a prognostic factor for survival outcome.
Patients and methods: This study included 59 subjects with SNSCC. We retrospectively collected the clinical features of these patients from medical records and retrieved the associated formalin-fixed, paraffin-embedded tissues for PDPN immunohistochemical staining. Furthermore, PDPN expression was analyzed in relation to the patients' clinicopathological features and prognosis.
Results: We observed positive staining for PDPN in both cancer cells and stromal cancer-associated fibroblasts (CAFs). Positive expression of PDPN in cancer cells of patients with SNSCC was significantly correlated with the primary tumor site (p = 0.009) and local recurrence (p = 0.024). In addition, patients with PDPN-positive cancer cells had significantly lower overall survival (OS) and disease-free survival (DFS) rates than did patients with PDPN-negative cancer cells (both p < 0.05). Multivariate analysis revealed that PDPN expression in cancer cells was an independent prognostic factor for both OS (p = 0.038) and DFS (p = 0.039).
Conclusions: Our findings demonstrated that PDPN overexpression may be both an independent prognostic biomarker and a therapeutic target in SNSCC.
Keywords: podoplanin; prognosis; sinonasal; squamous cell carcinoma.