Examination of factors predicting occult metastasis of the cervical lymph nodes in T1 and T2 tongue carcinoma.

Occult metastasis of the cervical lymph nodes was examined as a prognostic factor for T1 and T2 tongue carcinoma. The T classification and thickness of tongue carcinoma as well as histological malignancy were assessed respectively as clinical and histopathological factors related to metastasis. Sixty-eight patients who had undergone partial glossectomy for the treatment of T1 or T2 tongue carcinoma were studied. Occult metastasis of the cervical lymph nodes occurred in 15 out of 68 patients (22.1%). It occurred in 18.4% of T1 patients and 26.7% of T2 patients. Although the incidence of metastasis was higher in patients with larger tumors, a significant difference was not observed. Examination of the thickness of the tongue tumors revealed a mean value of 3.5 mm in patients without metastasis versus 5.5 mm in patients with metastasis, which was a significant difference. Examination of histological malignancy showed a significant correlation between the pattern of invasion and the incidence of occult metastasis to the cervical lymph nodes. There was a significant difference between the total score of the group without occult metastasis (12.8 points) and that of the group with metastasis (14.4 points). Improvement of the prognosis might be possible through elective neck dissection if occult metastasis to the cervical lymph nodes could be predicted.