Abstract
Introduction: We aimed to evaluate the prevalence of occult node metastasis in squamous cell carcinoma (SCC) of the larynx and to identify its predictive factors.
Methods: Our study is retrospective. We included all patients treated with salvage total laryngectomy (STL) for SCC of the larynx, clinically and radiologically classified as cN0, in the otolaryngology and head and neck surgery, radiotherapy and medical oncology departments of the Habib Bourguiba University Hospital of Sfax, over a period of 30 years (1993-2023).
Results: We included 16 cases of STL with an average annual incidence of 0.53 cases/year. A clear male predominance was noted with a sex ratio of 15 (15M/1F). The average age at the time of STL was 61 ± 13.3 years [41-81 years]. At the end of the initial treatment, continued tumour progression was observed in 8 patients (50%) and tumour recurrence in 8 patients (50%).
All patients had functional bilateral lymph node dissection (levels II, III, and IV). Eight patients underwent bilateral level VI dissection (50%). Pathological examination confirmed lymph node invasion ipsilateral to the tumor with pN+ capsular rupture in 5 patients (31.2%) with a median number of 2 positive nodes. Three patients presented with capsular rupture of pR+ nodes (18.7%). Four patients (25%), all pN+, died of their disease and overall survival and disease-free survival were 70% at 1 year. The presence of occult N+ lymph node metastases was linked to poor overall and disease-free survival (p=0.001).
The presence of pN+ lymph node metastases was statistically linked to supraglottic and subglottic recurrences.
Conclusion: The positivity of N+ metastases was linked to supraglottic and subglottic recurrences in a statistically significant manner, although in the literature the rate of occult metastases is higher for rT3-T4 and supraglottic involvement.
Keywords: Squamous cell carcinoma; Larynx; Lymph node metastasis; Lymph node dissection; Prognostic