Phase I-II trial of perioperative high-dose-rate brachytherapy in oral cavity and oropharyngeal cancer.

BACKGROUND

To determine the feasibility of combined perioperative high-dose-rate brachytherapy (PHDRB) and intermediate-dose external beam radiation therapy (EBRT) as an alternative to full-dose adjuvant EBRT in patients with unirradiated squamous cell cancer (SCC) of the oral cavity and oropharynx.

METHODS

Forty patients were treated with surgical resection and PHDRB. PHDRB dose was 4Gy b.i.d.x4 (16Gy) for R0 resections and 4Gy b.i.d.x6 (24Gy) for R1 resections, respectively. External beam radiotherapy (45Gy in 25 fractions) was added postoperatively. Patients with Stage III, IVa tumors, and some recurrent cases received concomitant cisplatin-paclitaxel chemotherapy during EBRT.

RESULTS

The rate of protocol compliance was 97.5%. Eleven patients (27.5%) developed RTOG Grade 3 or greater toxicity. Four patients (10%) presented complications requiring a major surgical procedure (RTOG 4), and one patient died of bleeding (RTOG 5). Three complications (7.5%) occurred in the perioperative period, and 8 (20.0%) occurred more than 3 months after the completion of the treatment program. Severe complications were more frequent in posteriorly located implants than in anterior implants (p=0.035). After a median follow-up of 50 months for living patients (range, 2.5-86.1+), the 7-year actuarial rates of local and locoregional control were 86% and 82%, respectively; and the 7-year disease-free survival and overall survival rates were 50.4% and 52.3%, respectively.

CONCLUSIONS

PHDRB can be integrated into the management of patients with resected cancer of the oral cavity who are candidates to receive postoperative radiation or chemoradiation. The local control and toxicity rates were similar to those expected after standard chemoradiation. PHDRB was associated with high toxicity in posterior locations, and the scheduled PHDRB dose was shifted to the closest lower level.