Central neck lymph node metastasis in oral squamous cell carcinoma at the floor of mouth

Background: Our goal was to analyze the incidence of level VI metastasis in previously untreated oral squamous cell carcinoma (SCC) patients and their clinicopathological and prognostic characteristics. Methods: Oral SCC patients with level VI metastasis were retrospectively enrolled, and their demographic and pathologic features as well as their survival data were descriptively analyzed. Results: A total of 13 cases from 1875 patients were included, all patients had SCC at the floor of mouth (SCCFOM). Eight (61.5%) patients had a pT4 tumor, and all patients had a pathological N3 neck with multiple positive lymph nodes. Adverse pathologic features were present in 100% of the patients. The size of the metastatic foci in level VI ranged from 2.6 cm to 4.5 cm with a mean value of 3.2 cm, and 5 patients showed a soft tissue deposit with no lymph node component. Recurrence occurred in all patients, and 11 patients died of uncontrolled cancer within 5 years after surgery. Conclusion: Level VI metastasis in primary oral SCCFOM is rare, and its prognosis is poor.