Human papilloma viruses (HPV) may cause head and neck squamous cell carcinomas. HPV associated carcinomas mostly occur in the oropharynx and particularly in the palatine tonsil and base of tongue. Carcinomas at other sites are infrequently caused by HPV. The viral proteins E6 and E7 are crucial for malignant transformation. They functionally interfere with cellular proteins maintaining genomic integrity such as p53 and cell cycle control such as retinoblastoma protein. However, unlike carcinogens such as tobacco smoke, the virus does not disrupt the coding genes. Reliable HPV detection methods in histological specimens include in situ hybridisation of high risk DNA and immunohistochemical detection of p16. HPV positivity does not proof a causal relation between HPV and tumour. High risk HPV are also detectable in 10-20% of normal mucosal specimens. Irrespective of the various modalities available for treatment, HPV associated head and neck cancers have a better prognosis than their carcinogen caused counterparts. HPV positivity does not object to surgical treatment.
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