Objectives: Supraomohyoid neck dissection (SOHND) is one of the treatment for clinically negative neck disease in carcinoma of the oral cavity when primary is treated with surgery. Neck tumor recurrence in these patients who were treated by SOHND with and without post-operative radiotherapy was evaluated.
Material and Method: Forty-four patients with squamous cell carcinoma of the oral cavity aged between 33-
78 years was studied. Every case had clinically negative neck and was treated with SOHND.
Results: There were 53 supraomohyoid neck dissections. The overall recurrence rate was 11.3% (6/53). The duration of recurrence ranged from six to nine months and was seen in five of pathologically negative neck and one in pathologically positive neck. Five of six of the recurrence cases were in the field of SOHND without post-operative radiotherapy. Histopathological review with immunohistochemistry study of all recurrent cases that was previously reported as negative by H&E stain showed no micrometastasis. The 5-yr survival of neck node metastasis was 64% versus 82% of these with no lymph node metastasis which showed no statistically significant difference.
Conclusion: The SOHND was useful for treating clinical negative neck of oral cancer with high percentage of occult lymph node. The pathological report influenced the adjuvant treatment. Micrometastasis and other indicators for this pathologically negative neck is still await further study to improve survival of this particular group of patients.

Keywords: Micrometastasis, Recurrent, Supraomohyoid neck dissection