skip to main content

p16-negative CUP Cervical Node — SCE Medical Oncology MCQ

Instant feedback + full explanation. One question, done properly.

HardCancer of Unknown Primaryp16-negative CUP Cervical NodeSCE Medical Oncology

A 55-year-old man is diagnosed with cancer of unknown primary (CUP). The initial investigation reveals a squamous cell carcinoma in a cervical lymph node. p16 testing is negative. EBV testing is negative. Nasopharyngeal examination and panendoscopy are normal. PET-CT does not identify a primary. What is the most likely occult primary site?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Lung

While p16-positive cervical nodal SCC strongly suggests oropharyngeal origin (>90% predictive value), p16-negative SCC has a broader differential. The most common occult primaries include: oropharynx (p16-negative HPV-negative subset), cutaneous head/neck SCC, lung and other upper aerodigestive sites. When panendoscopy and PET-CT fail to identify a primary, management includes: bilateral tonsillectomy (approximately 25% detection rate of occult tonsil primaries) and consideration of lingual tonsillectomy/BOT mucosectomy. Treatment is typically chemoradiotherapy to likely mucosal sites and involved neck.

Reference: NICE NG36 CUP; ESMO 2024 H&N and CUP Guidelines; Waltonen et al Laryngoscope 2009