Bilateral Neck Dissection in cN0 Supraglottic Squamous Cell Carcinoma: Essential or Not?

Objective: There is controversy regarding bilateral neck dissection for cN0 supraglottic squamous cell carcinoma. This study aimed to explore the risk factor of occult isolated contralateral/bilateral metastasis in cN0 supraglottic squamous cell carcinoma and help clinicians better make assessments for these patients.

Method: PubMed, the Cochrane Library, CNKI, and CBM were systematically searched for studies on occult lymph node metastasis in cN0 supraglottic squamous cell carcinoma from the inception of each database to May 30, 2024. All patients with supraglottic squamous cell carcinoma and a clinical N0 neck, who had complete records of neck lymph node metastasis, were included in the study. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline was followed to extract data. Data were pooled using a random-effects generalized linear mixed model with 95% confidence intervals (CIs). The risk of occult isolated contralateral/bilateral metastatic lymph nodes was analyzed.

Results: Fifteen studies including 1609 patients with cN0 supraglottic squamous cell carcinoma were analyzed. The pooled risk of occult isolated contralateral/bilateral metastasis was 7.49% (95% CI: 5.65%-9.87%; I² = 57%). For Type A tumors, the risk was 4.14% (95% CI: 2%-64%; I² = 81%), 6.74% for Type B (95% CI: 2.27%-18.33%, I² = 82%), and 13.62% for Type C (95% CI: 5.82%-28.66%, I² = 69%). For T1-T2 patients, the risk was 5.18% (95% CI: 2%-64%; I² = 81%), and 8.73% (95% CI: 5.92%-12.69%, I² = 0%)for T3-T4 patients. When ipsilateral pN+ was present, the risk increased to 20.97% (95% CI: 16.09%-26.85%, I² = 29%).

Conclusions: Contralateral neck dissection is recommended for Type C patients. Pathologically ipsilateral metastasis confirmed patients should receive contralateral neck dissection, radiotherapy, or even active surveillance follow-up.