Patterns of cervical lymph node metastases in oral tongue squamous cell carcinoma: implications for elective and therapeutic neck dissection.

OBJECTIVES: To determine the patterns of lymph node metastases in oral tongue carcinomas, and examine the implications for elective and therapeutic neck dissection. METHOD: The study entailed a retrospective analysis of 67 patients with previously untreated oral tongue squamous cell carcinoma who had undergone simultaneous glossectomy and neck dissection. RESULTS: Of the 40 clinically node-negative patients, 7 patients had metastatic lymph nodes on pathological examination. No occult metastasis was found at level IV. Of the 27 clinically node-positive patients, the incidence rate of level IV metastasis was 11.1 per cent (3 out of 27 patients). No 'skip metastases' were found at level IV. Level IV metastases were significantly related to clinically staged nodes categorised as over 2a (p = 0.03) and metastasis to level III (p = 0.01). CONCLUSION: Routine inclusion of level IV in elective neck dissection is not necessary for clinically node-negative patients with oral tongue squamous cell carcinoma. Furthermore, extended supraomohyoid neck dissection with adjuvant radiotherapy can be sufficient in the treatment of selected patients with clinically node-positive necks.