Radical radiotherapy for oropharyngeal carcinomas

The treatment results of 127 previously untreated patients with oropharyngeal carcinomas treated with radical radiotherapy between 1980 and 1995 were evaluated. Almost all patients were treated with external radiotherapy using cobalt gamma rays. The standard treatment schedule was one time per day, four times per week, with 2.5 Gy as the daily dose and 65 or 70 Gy as the total number of tumor doses. From the introduction of a CT simulator in 1988, patients who had an unilateral tumor that did not cross the midline and had no contralateral neck lymph node metastasis were treated by an ipsilateral technique (an anterior oblique and a posterior oblique field with 30 or 45 deg wedges) sparing contralateral parotid gland and excluding the contralateral neck region from the irradiated volume using CT simulator. In 38 patients who were treated by the ipsilateral technique, the treatment results were comparable with those in patients treated by the standard method in opposite fields and there was no contralateral regional failure. Moreover, radiation-induced xerostomia was significantly reduced in these patients. It was suggested that the ipsilateral technique may be indicated in patients with laterally located, not crossing the midline, T1-3, N0-2 tumors of the oropharynx with the help of CT simulator. The treatment results of 29 patients treated with the concomitant administration of radiotherapy and weekly carboplatin and 92 patients treated with radiotherapy without chemotherapy were compared. No significant difference in cause-specific survival, local control and neck control was found between the two groups. (author)