Prognostic value of the nodal yield in elective neck dissections in patients with head and neck carcinomas

Purpose The objective of this study is to assess the prognostic capacity of the nodal yield in elective neck dissections performed in patients with head and neck squamous cell carcinomas (HNSCC) without clinical or radiological evidence of regional involvement (cN0) at the time of diagnosis. Methods Retrospective study including 647 patients with HNSCC treated with an elective neck dissection. Results Patients with < 15 dissected nodes ( n = 172, 26.6%) had a 5-year disease-specific survival of 64.9% (95% CI: 57.3–72.5%), while for patients with ≥ 15 dissected nodes ( n = 475, 73.4%), it was of 81.9% (95% CI: 78.4–85.4%) ( P = 0.0001). The nodal yield category had prognostic capacity on the disease-specific survival in patients with tumors located in the oral cavity ( P = 0.001), the oropharynx ( P = 0.023) and the hypopharynx ( P = 0.034), while for patients with tumors located in the larynx, no significant differences appeared ( P = 0.779). Differences in regional recurrence-free survival were also observed based on the nodal yield category in patients with extra-laryngeal tumors (5-year regional recurrence-free survival of 81.0% in patients with < 15 dissected nodes vs 89.0% in patients with ≥ 15 dissected nodes; P = 0.046). Conclusion The nodal yield in elective neck dissections in patients without evidence of lymph node disease (cN0) had prognostic capacity depending on the location of the primary tumor. For tumors located in the larynx, the number of dissected nodes did not significantly influence the prognosis. For tumors located in the oral cavity, oropharynx or hypopharynx, patients with < 15 dissected nodes had a disease-specific mortality 2.9 times higher than patients with ≥ 15 dissected nodes.