頭頸部のヒト乳頭腫ウイルス感染

抄録

Human papillomavirus (HPV) infection is frequently observed in the head and neck region and has become a common cause of oropharyngeal squamous cell carcinoma (OPSCC), although the detailed mechanism underlying the pathogenetic process from infection to carcinogenesis remains unclear. A new staging system has been proposed in the 8th edition of the American Joint Committee on Cancer (AJCC) Staging Manual, which reflects the HPV infection status in determining the clinical stage of OPSCC. The 8th edition of the AJCC Staging Manual adopted p16 immunohistochemistry as a surrogate marker of HPV infection. Although p16 immunoreactivity is a clear indicator of HPV-mediated OPSCC, the significance of p16 immunoreactivity in other head and neck cancers has yet to be confirmed. It is very important to employ polymerase chain reaction (PCR) assay for the detection of HPV infection, while using appropriate control conditions and ensuring adequate sample quality, to prevent false-negative as well as false-positive results. In addition, establishment of a risk classification system and less-invasive treatment protocol for HPV-mediated head and neck cancer is also necessary.

The low-risk types of HPV infection, namely, HPV-6 and -11, are observed in nearly all cases of recurrent laryngeal papilloma. Patients, especially children, suffer from laryngeal papilloma because of frequent recurrence and airway obstruction, although the rate of malignant transformation is low. Elucidation of the mechanism of recurrence is important to devise a new treatment protocol.