Background & objective: There was little report on the rule of lymph node metastasis in the cancer of mouth floor. The aim of this study was to investigate the rule of lymph node metastasis and investigate the reasonable treatment.
Methods: A total of 79 cases with squamous carcinoma of mouth floor were included into this study retrospectively. The distributive difference of clinical and pathological positive lymph node was compared. The recurrent rate of the patients who were performed with radical neck dissection and supra-half-neck dissection in clinical positive lymph node group were compared with the recurrent rate of the patients who were preformed with radical neck dissection, supra-half-neck dissection, submandibular triangle dissection, and clinical observational group.
Results: Clinical and pathological positive lymph node was found mainly in II region (61.8% and 40.0%, respectively), secondly in I and/or III region, and rarely in IV, V, and VI region. In clinical positive lymph node group, the recurrent rate of the patients who performed with radical cervical neck dissection was lower than supra-half-neck dissection, but without statistical significance (chi 2 = 3.403, P = 0.065). In clinical cervical negative lymph node group, the recurrent rates of the patients performed with supra-half-neck, submandibular triangle dissection, and in clinical observational group were 11.1% (1/9), 40.0% (2/5), and 23.5% (4/17), without statistical significance (chi 2 = 1.554, P = 0.46).
Conclusion: Lymph node metastasis of cancer of floor of mouth mainly distributes in I, II, III region; The patients with negative cervical lymph node should be performed lymph node dissection in I, II, III region (supra-half-neck).