The role of pathologist in the diagnostics of HPV-associated squamous cell carcinomas of head and neck
Abstract
HPV-associated oropharyngeal squamous cell carcinoma is nowadays regarded as a distinct clinico-pathological entity, characterized by younger age of the patients who are frequently non-smokers, association with sexual behaviour, and improved prognosis when compared with HPV-negative carcinomas of the oropharynx. HPV status of oropharyngeal carcinomas provides important prognostic information, is necessary inclusion criterion for clinical trials, and even replaces traditional histopathological grading system.
The role of pathologist (with cooperation with geneticist) is to determine the presence or absence of transcriptionally active HPV infection in all carcinomas occurring at this anatomic area. For this purpose, combination of PCR, detecting presence of HPV DNA, with immunohistochemical examination of protein p16 expression is most frequently utilized.
Only p16-positive (GREATER-THAN OR EQUAL TO 70% positive tumor cells) and HPV DNA-positive tumors may be regarded as HPV-associated. The prevalence of transcriptionally active HPV infection in non-oropharyngeal carcinomas of the head and neck is much lower than was previously thought and their routine p16/HPV testing is currently not recommended.