Human papillomavirus and World Health Organization type III nasopharyngeal carcinoma: Multicenter study from an endemic area in Southern China.

BACKGROUND: The current study was conducted to study the incidence of human papillomavirus (HPV)-associated nasopharyngeal carcinoma (NPC) in Southern China and the corresponding treatment outcome. METHODS: A retrospective chart review with a level of evidence of 4 was performed. RESULTS: Between 2000 and 2015, a total of 1328 patients with NPC were treated in 3 study institutes in Hong Kong and Foshan City in Guangdong Province, China. All tumors were undifferentiated, nonkeratinizing carcinoma, of which 91.9% were positive for the Epstein-Barr virus (EBV+) and 7.7% were positive for HPV/p16 (HPV+). Although coinfection with both viruses occurred only in 8 patients (0.6%), 94 patients had tumors that were EBV negative (EBV-) and HPV+. All patients were treated with intensity-modulated radiotherapy alone for American Joint Committee on Cancer stage I and II disease, and concurrent chemoradiotherapy for stage III and IV disease. With a median follow-up of 72.8 months, the authors found that the local recurrence rate was significantly lower for patients with tumors that were EBV-/HPV+ compared with patients with tumors that were EBV+/HPV- (6.4% vs 13.8%; P = .03). Similar trends were observed for the 5-year disease-free survival rate (89.8% vs 70.8%; P =.03) and 5-year overall survival rate (86% vs 72%; P =.03). CONCLUSIONS: In regions that are endemic for NPC, the prevalence of EBV and HPV coinfection in patients with NPC is extremely low. Conversely, patients with EBV-/HPV+ NPC demonstrate significantly better local tumor control and survival after radiotherapy. Cancer 2018;124:530-6. (c) 2017 American Cancer Society.