Botulinum Toxin (Dysport) to Prevent Radiation-Induced Dysfunction of Salivary Glands in Head and Neck Cancer

The main goal of this pilot trial was to investigate the efficacy of botulinum toxin (Dysport) injection before radiotherapy in preserving salivary gland secretion in patients with head and neck cancer.

Sixteen patients with head and neck cancer were enrolled, 9 received 50 IU Dysport, and 7 recieved NaCl (0.9%) into the submandibular glands before chemo-radiotherapy. To investigate the salivary gland function, technetium pertechnetate salivary gland scintigraphy, as well as saliva accumulation and the University of Washington Quality of Life (UW-QoL) Questionnaire were utilized "before" and "6 months after the end" of radiotherapy.

Sixteen patients were randomized (9 botulinum toxin, 7 placebo). Baseline characteristics were comparable between groups. At 6 months post-radiotherapy, basal saliva volume was higher in the botulinum toxin group (median 5.0 cc vs. 2.0 cc; p < 0.001) as was stimulated saliva volume (6.0 cc vs. 2.0 cc; p < 0.001). UW-QoL scores were significantly lower, indicating better quality of life, in the botulinum toxin group (37.0 vs. 67.0; p < 0.001). Covariate-adjusted analyses confirmed botulinum toxin as the only significant predictor of saliva preservation and improved QoL.

A single injection of botulinum toxin before radiotherapy preserves salivary gland function and improves quality of life. Based on these findings, we advocate for a multicenter Phase II trial to define the optimal dose-response relationship and determine the ideal timing for injection relative to the start of radiotherapy.