Accelerated irradiation of cervical node metastases.

Abstract

Accelerated irradiation combining electron beam and cobalt sources was carried out in 34 patients with large involved nodes fixed to the cervical structures (N3). Concomitant boost technique was used to reduce the overall duration of treatment from 7 to 5 weeks while maintaining the standard 70-Gy tumor dose. The first part of treatment consisted of conventional cobalt irradiation, 50 Gy delivered to the whole neck over 5 weeks. The accelerated schedule, carried out over 4 weeks, delivered an additional 1 Gy/day to the node through a circular and lateral electron beam field, for a total dose of 70 Gy to the enlarged node. In the case of an identified primary the tumor site was also boosted to the 70-Gy total dose. The rate of acute skin reactions was acceptable and there were no major mucosal complications. At the end of irradiation, 62% of patients experienced complete clinical regression; 41% subsequently had cervical recurrences. Early cervical fibrosis was limited to the over-treated area. The concomitant boost technique is a good way to accelerate irradiation without decreasing the total dose or increasing the immediate complication rate.