Tests Emerging as Standards for Diagnosing HPV-Positive Oropharyngeal Cancer

One of the main challenges to managing the increased incidence of HPV-positive oropharyngeal cancers is correctly diagnosing the disease. Unlike cervical cancer, where all cases are assumed to be HPV-positive, clinicians would like to know which oropharyngeal cancers are driven by HPV and which are not. At present, most institutions are using two tests, either alone or in combination, said Dr. Sturgis, and these are emerging as probable standards.

One test is immunohistochemical analysis of p16 expression levels in tumor tissues, as p16 overexpression appears to be a very specific sign of an HPV-driven oropharyngeal cancer. The second test uses in situ hybridization, which has a high sensitivity to detect many types of oncogenic HPV, and is often used as a confirmatory test if p16 immunohistochemistry is positive.

Caution is urged, however, when using serological testing alone. “We need to be very cautious when people come in with positive HPV DNA results, because the infection in many of these people will clear on its own,” said Dr. D’Souza, who added that “we need to think about whether to do HPV DNA screening and how to counsel people about this type of screening.”