Salvage Neck Dissection in Recurrent Head and Neck Squamous Cell Carcinoma After Primary Radiotherapy (RESCUE): An IReC Multicentre Consecutive Cohort Study.

BACKGROUND: To investigate the outcomes of salvage neck dissection (sND) in recurrent head and neck squamous cell carcinoma (rHNSCC) with clinically positive and negative cervical lymph nodes. METHODS: Analysis of a retrospective multicentre observational cohort was performed. All patients undergoing sND for cN0 or cN positive disease between 1st January 2016 and 31st December 2022 were included. Survival analysis was stratified according to nodal status and extent of sND. RESULTS: Data from 235 sNDs for rHNSCC after primary radiotherapy were included. Median age was 63 (IQR 57-70), and 121/225 (53.8%) had cN0 nodes, whilst 104/225 (46.2%) were cN+. Superselective, selective, and radical/modified radical sNDs were performed in 45 (19.3%), 152 (65.2%), and 36 (15.5%). Superselective sND was associated with a shorter median inpatient stay than selective resections (15 vs. 18 days, p = 0.002). Occult pN+ nodal disease was seen in 13/108 (12%). There were no significant predictors for occult nodal disease. Five-year overall, disease-free, disease-specific, and regional recurrence free survival was 63.3%, 53.0%, 74.2%, and 56.9%. There was no significant difference in any time-to-event endpoint between superselective, selective, and radical/modified radical sND for cN positive disease, nor was there any significant survival difference between selective/superselective sND and observation alone in all cN0 cancers or in cN0 oropharyngeal recurrence only. CONCLUSIONS: Occult disease in cN0 cervical lymph nodes is uncommon and may therefore be safely managed with clinical observation. If the clinical and radiological disease is addressed, survival outcomes are similar across the ND types in cN0 and cN positive disease, implying more conservative excisions do not adversely influence disease control.