[en] From 1967 through 1988 183 previously untreated patients with squamous-cell carcinoma of the tongue were treated with electron beam irradiation. The patients were restaged as stage I (38 patients), stage II (64), stage III (58), and stage IV (28). For evaluable patients treated with intra-oral cone irradiation (IOC) alone (n=53) or combined with external irradiation (n=120), the two-year local control rate was 85% for T1, 73% for T2, and 58% for T3. According to clinical features, it was 80% for tumorous type, 68% for small ulceration type, and 53% for large ulceration type. In comparing uneven and even fractionated irradiation procedures, there was no significant difference in two-year local control rate (68% for uneven fractionated irradiation vs. 61% for even fractionated irradiation). When restricting to T2 and T3 patients, it was significantly higher for uneven fractionated irradiation (77% and 63%) than even fractionated irradiation (56% and 40%). In comparing T3 patients categorized as having >1000 mm² (I) with those as having ≤1000 mm² (II). the two-year local control rate was 48% for category I and 72% for category II. For T3 patients, it was 43% when associated with ulcer, as compared with 74% without it. The actuarial five-year survival rate was 92% for stage I, 72% for stage II, 67% for stage III, and 12% for stage IV. Delayed radiation ulcer and bone exposure were seen in 22 and 7 patients, respectively. In conclusion, IOC is comparable to internal irradiation and is clinically effective for T1 through T3 (in smaller size) tongue cancer. (N.K.)