Treatment of the clinically negative neck in floor of the mouth carcinoma.

A retrospective study of 61 consecutive patients with floor of mouth carcinoma and a clinically negative neck was done to determine the value of elective treatment to the neck. Subsequent histologically proven nodal disease was analyzed according to initial treatment modality (23 surgical, 38 irradiation), stage (29--T1,27--T2,5--T3), hemi-neck at risk (midline lesions placed both hemi-necks at risk), and primary control for a minimum of 2 years (50 patients, 78 hemi-necks at risk). Neck failures were classified by T stage, extent of neck treatment (upper neck or complete) and by primary control at the time of manifest neck metastasis. Of the hemi-necks at risk with the primary controlled, 10% (17% of patients) developed nodal disease without complete neck treatment; 86% (6/7) of these patients were salvaged. The occult positive node incidence, conservatively calculated by elimination of all patients treated with elective partial or total neck irradiation, was 10% for patients with T1 and T2 lesions (7% for hemi-necks at risk). Based on the clinical course of patients with primary control, only 1 patient (2%) might have benefited from initial complete elective neck treatment. These results suggest that elective neck treatment in early (T1 and T2, N0) floor of mouth carcinoma is of doubtful value. Supraomohyoid , rather than suprahyoid dissection, is recommended if surgical treatment of the neck is undertaken.