Human papillomavirus–related oropharyngeal cancer: HPV and p16 status in the recurrent versus parent tumor

Abstract

Background Although typically associated with a favorable prognosis, a minority of human papillomavirus (HPV)‐related (+) oropharyngeal cancers recur after chemoradiation. We postulated that a minor HPV‐negative tumor subfraction may be responsible for recurrences of HPV+ oropharyngeal cancer. Methods Paired untreated primary and recurrent tumor specimens were identified for 37 patients with oropharyngeal cancer who received definitive chemoradiotherapy at our institution. Concordance in HPV/p16 expression between primary and recurrent tumors was assessed. Results Among 31 patients with HPV+/p16+ primary tumors, 30 (97%) retained evidence of both HPV and p16 expression at recurrence (27 HPV+/p16+; 3 HPV+/p16‐partial). One (3%) initially HPV+/p16+ patient developed an HPV‐negative/p16‐negative lung squamous cell carcinoma (SCC), representing either a discordant oropharyngeal cancer metastasis or second primary tumor. Conclusion HPV‐related oropharyngeal cancers retain HPV+/p16+ expression at recurrence. Our results fail to provide evidence that a minor HPV‐negative tumor subfraction is responsible for biologically aggressive behavior of HPV+ oropharyngeal cancer that recurs after chemoradiation. © 2014 Wiley Periodicals, Inc. Head Neck 37 : 8–11, 2015