If a cervical lymph node is positive for p16, where should one look for more information regarding the primary site?

When a cervical lymph node is positive for p16, it indicates a strong association with HPV-related malignancies, particularly those originating from the oropharynx. p16 is a cyclin-dependent kinase inhibitor that is typically overexpressed in HPV-associated cancers, especially in the oropharyngeal region. Consequently, the primary tumor site is likely to be located in the oropharynx, making the oropharynx p16+ chapter the most relevant source of information for further investigation into the primary site of the disease.

The oropharynx is a common site for HPV-related carcinomas, and understanding the p16 positivity in cervical lymph nodes often implicates an oropharyngeal primary, thus guiding the clinical evaluation and staging of the patient. This context helps in identifying appropriate treatment options and improving patient management.

In contrast, the other chapters—larynx, throat, and cervix—while related to head and neck cancers or cervical cancers, do not focus specifically on the implications of p16 positivity in the same way that the oropharynx chapter does. Therefore, the oropharynx p16+ chapter is the best resource for uncovering further information regarding the primary malignancy associated with a positive p16