POST-OPERATIVE SPLIT COURSE RADIOTHERAPY OF SQUAMOUS-CELL CARCINOMA OF THE ORAL TONGUE

Forty nine patients with squamous cell carcinoma of the oral tongue were irradiated postoperatively using a split course technique for external irradiation alone or in combination with intraoral cone X-ray therapy. After a 3 year follow-up the results of local control were compared with those of other authors, who irradiated initially with combined external and interstitial therapy in one series. For two series the nominal standard dose (NSD) was calculated with the modified Ellis formula given by Gabriel-Jurgens et al.10 and Gremmel et al.11 In our patient collective the recurrence rate was higher in the early T-stages, because the dosage applied was lower than in the majority of the cited publications. The combined modality of surgery and following external irradiation could not improve the outstanding results of interstitial therapy in T1 and T2 tumors. When the split course technique is used, the total dose and treatment time must be increased to obtain the same local control rate as in one series irradiation. Especially in advanced cases the split dose regimen seems to be an alternative treatment, because severe complications were not observed in our patients. For split course therapy we recommend the application of 1700 ret for Stage T1 oral tongue carcinoma 1800 ret for Stage T2 and 1900 ret for T3 tumors. For treatment of recurrences, surgery appears to be superior to irradiation. © 1979.