Phase I/II study of high-dose rate interstitial radiotherapy for head and neck cancer.

From July 1991 through December 1991, a phase I/II study of high-dose rate interstitial radiotherapy for head and neck cancer was performed to determine any acute adverse effects and mucosal reaction as well as the feasibility of this therapy. A total of seven patients with head and neck cancer (tongue: four cases; mouth floor: one case; buccal mucosa: one case; oral mucosa of lower lip: one case) were entered into this study. The dose schedule of high-dose rate interstitial radiotherapy ranged from 35 Gy/ten fractions (bid)/week to 60 Gy/ten fractions/week. No major or minor early complication was observed. Spotted mucositis appeared starting three days after the end of high-dose rate interstitial radiotherapy while confluent mucositis developed and approached a peak at ten days but disappeared by the fourth to eighth week. Early tumor responses of all patients were complete.