Impact of retropharyngeal lymph node metastasis in head and neck squamous cell carcinoma

Background: The impact of metastasis to the retropharyngeal lymph node (RPLN) group is poorly understood because of the difficult access of the retropharyngeal space. Previous studies concluding to the negative impact of RPLN metastasis rely heavily on radiographic assessment, which introduces the possibility of diagnostic error. Objective: To better define the prognostic significance of metastatic retropharyngeal adenopathy in patients with non-nasopharyngeal squamous cell carcinoma of the head and neck. Study Design: A retrospective cohort study of patients with non-nasopharyngeal squamous cell carcinoma of the head and neck who underwent resection of the RPLN group and were followed up for an average of 24 months. Setting: Tertiary care academic medical center Patients: The 51 patients included in the study had been treated for advanced-stage squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, and/or supraglottic larynx via a surgical approach to the primary tumor that afforded access to the RPLN group. All patients underwent dissection and pathologic interpretation of the RPLNs, most patients received postoperative radiotherapy, and 43 patients met survival analysis criteria. Main Outcome Measures: Local and regional recurrence rates, the development of distant metastasis, and disease-free and overall survival. Results: Metastasis to the RPLN group was confirmed pathologically in 14 (27.5%) patients. There was no statistically significant difference between patients with and without RPLN metastasis in rates of local recurrence (24.8% vs 28.4%), regional recurrence (17.5% vs 19.6%), distant metastasis (17.0% vs 11.2%), disease-free survival (40.51% vs 30.5%), and overall survival (40.6% vs 38.5%). Conclusion: Metastasis to the RPLN group does not impact disease control or survival in patients with advanced non-nasopharyngeal squamous cell carcinoma of the head and neck treated with multimodality therapy.