Prophylactic gabapentin decreases fatigue and swallowing difficulty in patients undergoing concurrent chemo-radiation (CCR) for head and neck cancer (HNC): Interim results from a randomized controlled trial.

Abstract

6059 Background: Preliminary data suggest that gabapentin (G) administered during HNC radiation may decrease treatment associated pain. To confirm this, we undertook a prospective, randomized trial in HNC patients undergoing CCR. Primary outcomes: pain severity (scale of 0-10) and opioid use. Exploratory outcomes: local and systemic symptoms measured by the Vanderbilt Head and Neck Symptom Survey version 2 plus the general symptom survey (VHNSSv2/GSS). We report results of the exploratory endpoints from the interim analysis. Methods: Measures: VHNSSv2 - 50 items, demonstrated reliability/validated, captures acute/chronic local HNC specific symptoms; GSS – 11 item checklist, demonstrated content validity, captures acute/chronic systemic symptoms. Population: HNC patients (≥ stage 2) undergoing primary or adjuvant CCR. Procedures: Randomized to standard pain management (SPM) or SPM + G dose escalated to 900mg tid. VHNSSv2/GSS completed weekly during treatment beginning week 1 and ending the last week of radiation therapy. Results were analyzed using a mixed-effects regression analysis adjusting for baseline levels of each symptom. Results: 71 patients completed a mean of 5.5 surveys. Patients on G experienced a reduction in overall systemic symptoms as measured by the GSS (11-items, p = 0.0073), fatigue (two-items, p = 0.013 ) sleep disturbance (five items, p < 0.0001) , neurosensory eating (3 items, p = 0.026), phlegm-related symptoms (4 items, p = 0.004), and trend to better smell (2 items, p = 0.055). No impact on swallow, xerostomia, voice, dental or musculoskeletal symptoms was noted. Conclusions: This exploratory analysis suggests that G may moderate neurological and neuropsychiatric toxicities in HNC patients undergoing CCR. Further studies are warranted.