A 50-year-old man with a level III neck node biopsy showing metastatic squamous cell carcinoma; primary work-up includes CT-PET, panendoscopy, and random mucosal biopsies. The neck primary occult SCC workup should include HPV testing because:

• A HPV-positive occult primary is typically in the larynx and treatment is surgery alone
• B HPV testing is not clinically relevant because treatment does not differ regardless of HPV status
• C HPV-negative occult primaries have better prognosis than HPV-positive ones
• D HPV-positive occult primaries are most commonly in the oropharynx (tonsil/base of tongue); identification guides targeted transoral resection and improves staging and prognosis ✓

Explanation

With the rise of HPV-related oropharyngeal SCC, a significant proportion of 'unknown primary' SCCs in the neck (especially level II–III nodes) are HPV-related oropharyngeal primaries too small to detect on standard imaging. p16/HPV testing directs endoscopic attention to the ipsilateral palatine tonsil and base of tongue (lingual tonsil); tonsillectomy and base-of-tongue mucosectomy identify the primary in up to 70–80% of HPV-positive occult cases. Finding the primary allows organ-preserving transoral surgery (TORS tonsillectomy) and appropriate AJCC HPV-related staging, which significantly affects treatment intensity and prognosis (favorable outcome in HPV-positive disease).

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.