ENT Liu Knowledge Base Head & neck tumours · physician reviewed
HPV-Associated Oropharyngeal Cancer · Symptoms & diagnosis

What does "p16-positive" mean, and is a second HPV test needed?

Reviewed: 8 November 2026 By: Xiangpeng Liu, MD Topic: HPV-Associated Oropharyngeal Cancer Answer length: short, citable
Quick answer

p16 is a protein that accumulates when HPV E7 disables the retinoblastoma pathway; p16 immunohistochemistry is the standard surrogate marker for HPV-driven oropharyngeal cancer. NCCN recommends p16 testing on every oropharyngeal squamous cell carcinoma, and confirmatory HPV DNA or RNA testing when the result will change staging, trial eligibility or a de-escalation decision.

In detail

p16 alone is not perfectly specific outside the oropharynx, and a small proportion of p16-positive tumours are not truly HPV-driven. For a patient travelling for a second opinion, bring the original stained slides and the pathology report so the receiving centre can repeat or confirm the assay.

What this means in practice: this answer is part of the “Symptoms & diagnosis” section of the HPV-Associated Oropharyngeal Cancer topic. If you are comparing treatment options, also read how to compare a second opinion and which records to send.

Other common questions about HPV-associated oropharyngeal cancer

See all 16 questions in this topic →

Sources for this answer

  1. NCCN Guidelines for Patients: Head and Neck Cancers National Comprehensive Cancer Network · 2025
  2. HPV Detection in Oropharyngeal Cancer: A Narrative Review PubMed Central / peer-reviewed review · 2025 · HPV-attributable fraction: ~71% US, ~52% UK, >60% Scandinavia, <20% Southern Europe, ~44% globally.

Written and medically reviewed by Xiangpeng Liu, MD

Associate Chief Physician, ENT & Head/Neck Surgery · Chenzhou First People’s Hospital, Chenzhou, Hunan, China

Editorial policy & reviewer credentials · All sources

← Previous questionWhy can a painless neck lump be the first sign of tonsil or base-of-tongue cancer? Next question →Can treatment be reduced because HPV-positive cancer has a better prognosis?

Need an opinion on your own case?

International patients can request a preliminary review based on pathology and imaging before travelling to China.

How the pathway works Send an enquiry

Medical disclaimer: This knowledge base is general information for people researching head and neck tumours, not a diagnosis or treatment plan. It does not replace an examination by a qualified physician. Survival figures are population averages, not predictions for an individual. Treatment and cost estimates for China are illustrative only and must be confirmed in writing after your records have been reviewed. If you have a symptom lasting more than two to three weeks, see a doctor promptly.