Head and Neck Lymph Node Metastases From Cancer of Unknown Primary: Outcomes From p16-Guided Mucosal Radiotherapy
In brief
Reduced radiation volume in p16-positive unknown primary gives 90% five-year survival
In a retrospective series of 126 patients with head and neck cancer of unknown primary, those whose tumors were p16-positive received a limited ipsilateral mucosal radiation field and achieved a five-year overall survival of 90%, comparable to the 69% seen in p16-negative patients receiving comprehensive irradiation. Acute severe toxicity rates were similar, suggesting that de-intensified radiation is oncologically safe for p16-positive disease, though prospective validation is still needed.
- Journal
- Head & neck (Q1)
- Published
- 28 August 2026
- Study design
- Retrospective cohort
- Evidence level
- Level 3, Low (CEBM 3b)
- Authors
- Philippe Harris, Dhiya-Eddine Mabrouki, Felix-Phuc Nguyen-Tan, Edith Filion, Olivier Ballivy, Brian O'Sullivan, et al.
- PMID
- 42666021
- DOI
- 10.1002/hed.70431
Why clinicians should know about it
- Picked for Otorhinolaryngology (paper of the day, 2 September 2026): p16‑guided mucosal volume reduction safe in HNCUP patients
Abstract
BACKGROUND: The AJCC 8th edition distinguishes p16-positive oropharyngeal head and neck carcinoma of unknown primary (HNCUP) due to its superior prognosis. However, standardized radiation volume guidelines are lacking. This study evaluates the safety of p16-guided mucosal volume reduction. METHODS: A retrospective review of 126 HNCUP patients (2009-2023) was conducted. p16-negative patients received comprehensive mucosal and laryngeal irradiation; p16-positive patients received risk-adapted, reduced-volume radiation limited to the ipsilateral naso- and oropharyngeal mucosa and elective nodal regions. Acute and late toxicities were reviewed. RESULTS: The cohort included 97 p16-positive and 29 p16-negative patients (median follow-up 38 months). Five-year overall survival was 90.0% versus 69.2% for p16-positive and p16-negative patients. All mucosal emergences and neck recurrences occurred within the radiation fields. Acute grade 3 toxicities were comparable between groups. CONCLUSIONS: p16-guided mucosal volume reduction in HNCUP appears oncologically safe, without compromising disease control or survival, supporting radiotherapy volume de-intensification for p16-positive disease.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.