One hundred and ten patients with Stage II epidermoid carcinomas of the mobile tongue were treated by interstitial irradiation (Group I: 85 patients) or external irradiation to the primary and the regional lymphatics followed by an interstitial boost (Group II: 25 patients). The neck was managed by either an elective neck dissection (43 patients) completed by external irradiation in 13 patients with pathological specimen or close follow-up (40 patients) with therapeutic neck dissection for relapses (7 patients) in Group I. Primary local control was 88% in Group I and 36% in Group II. Regional control was 91% in Group I and 5/6 in Group II for patients whose primary tumor was controlled. Five-year absolute disease-free survival (DFS) was 42% in Group I and 24% in Group II, but there was an imbalance in the distribution of larger tumors favoring Group I. There were 30 radiation-induced complications and four patients required corrective surgery. This retrospective analysis showed better results in patients whose primary was treated by interstitial irradiation alone which has the extra advantage of preserving salivary function.