Comparison of radiotherapy types in the treatment of sialorrhea in amyotrophic lateral sclerosis

Abstract

Objectives: Many patients with amyotrophic lateral sclerosis (ALS) develop progressive difficulty swallowing secretions, leading to drooling. Although external beam radiation is considered to be an effective and well-tolerated treatment, the optimum schedule in terms of dose, target, radiation type, and number of fractions is unknown. The aim of this observational study was to define the most effective schedule for salivary gland irradiation and to compare electron and photon radiotherapy.

Methods: Sixteen patients with ALS (12 females and 4 males) with drooling, enrolled for external radiation of salivary glands between 2002 and 2007, were included. Patients received different treatment protocols according to the decision of their radiotherapist. Efficacy and safety were assessed at 1 and 6 months after treatment by a neurologist and a radiotherapist using a 4-point Likert patient improvement scale, as follows: 0 (no change), 1 (slight improvement), 2 (good improvement), and 3 (very good improvement).

Results: Radiotherapy for drooling was shown to be safe and effective in ALS patients with duration of effect expected up to 6 months. Eighty percent of patients felt improved at 1 month and 43% at 6 months after external radiation. Patients with sustained improvement at 6 months were treated with electron therapy (>8 MeV; p = 0.02).

Conclusions: Electron-based radiotherapy, delivered as five 4Gy fractions to a total dose of 20 Gy, encompassing the whole of the submandibular gland and sparing the upper part of the parotid gland, can be proposed as a safe and effective schedule for the treatment of sialorrhea in patients with ALS.