Human papillomavirus (HPV)-positive tonsillar carcinomas are frequent and have a favourable prognosis in males in Norway

CONCLUSIONS: This study confirms a high prevalence of human papillomavirus (HPV)-positive tonsillar tumours (52%). The survival of the HPV-positive group was significantly better in males. OBJECTIVES: We assessed the prevalence of HPV in 137 patients with tonsillar carcinomas, measured the p53- and Ki-67-positive tumour cell fractions and correlated the results with clinical variables. PATIENTS AND METHODS: Tumour DNA from patients with squamous cell carcinoma of the tonsillar region was amplified by PCR and sequenced for detection of HPV subtypes. RESULTS: HPV was found in 71/137 (52%) of the tumours; HPV-16 was the most frequent subtype (87%). HPV positivity did not correlate with gender, stage, T- and N categories, Ki-67 expression or p53 positivity. The HPV-positive group had a significantly better survival (p < 0.01) compared with the HPV-negative group in males. In a multivariate analysis HPV status gave prognostic information in addition to the earlier established factors, i.e. age, gender and stage (p < 0.05).