Prognostic value of p16 expression in Epstein-Barr virus-positive nasopharyngeal carcinomas

Overexpression of p16 is associated with improved outcomes among patients with oropharyngeal carcinoma. However, its role in the outcomes of patients with nasopharyngeal cancer (NPC) remains unclear.Eighty-six patients with NPC treated at MD Anderson Cancer Center from 2000 to 2014 were identified. Epstein-Barr virus (EBV) and human papillomavirus (HPV) status were determined by in situ hybridization (ISH) and p16 by immunohistochemical staining.EBV positivity was associated with extended overall survival (OS; median, 95.0 vs 44.9 months; p.004), progression-free survival (PFS; median, 80.4 vs 28.1 months; p.013), and locoregional control (median, 104.4 vs 65.5 months; p.043). In patients with EBV-positive tumors, p16 overexpression correlated with improved PFS (median, 106.3 vs 27.1 months; p.02) and locoregional control (median, 93.6 vs 64.5 months; p.02).P16 overexpression is associated with improved PFS and locoregional control in patients with EBV-positive NPC. P16 expression may complement EBV status in predicting treatment outcomes for patients with NPC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1459-E1466, 2016.