Therapeutic results for 100 patients with cancer of the mobile tongue treated with low dose rate interstitial irradiation

Aim: To evaluate the conservativeness of low dose rate interstitial irradiation (LII) for cancer of the mobile tongue. Patients and Methods: Between 1975 and 2002, 100 consecutive patients (71 men, 29 women) underwent LII as curative treatment. Stages were I/II/III/IV= 16/63/16/4. Seventy-one cases were treated with LII alone and 29 cases treated combined with external irradiation. Median total dose of LII was 70 Gy 17 days. Results: Overall, 5- and 10-year local control and LII-treated patients' survival rates were 93% and 91%, 64% and 57%, respectively. Delayed neck metastases were observed in 21% of initially N0 cases, 56% of which could be salvaged by operation. Early stage and well-differentiated tumors carried better prognoses. Conclusion: LII of cancers of the mobile tongue results in good local control and survival. With careful monitoring of patients to ensure early detection of delayed metastases, LII should allow organ conservation and yield favourable therapeutic results compared with those of surgery.