The role of prophylactic neck dissection and tumor thickness evaluation for patients with cN0 tongue squamous cell carcinoma

Purpose. Prophylactic neck dissection (PND) for patients with clinically N0 (cN0) tongue carcinoma remains controversial. We assessed the efficacy of PND for patients with cN0 tongue squamous cell carcinoma (SCC) and investigated the prognostic role of tumor thickness as assessed by diagnostic imaging in predicting the risk of nodal micrometastasis or late nodal recurrence. Methods. Eighty-eight patients with cN0 tongue carcinomas underwent surgical treatment. Tumor thickness was measured from magnetic resonance (MR) images or computed tomography (CT) scans. Results. The overall survival rates of patients with or without PND were 94% and 81%, respectively (p=0.2857). MR images or CT scans were available for 68 patients. A tumor thickness ≧10mm or ≧5mm did not increase the probability of nodal metastasis, with late nodal metastasis observed in 15% of patients with graphically undetected small tumors. Conclusions. PND appears to have the potential to improve overall survival for patients with cN0 tongue SCC. Careful follow-up management or PND is considered to be needed regardless of tumor thickness in the pre-treatment evaluation.