Randomized trial of standard pain control with or without gabapentin for pain related to radiation-induced mucositis in head and neck cancer

Abstract

Objective: Radiation-induced mucositis (RIM) in chemoradiotherapy (CRT) for head and neck cancer (HNC) causes severe pain and worsens CRT compliance, QOL and outcome. Following retrospective reports, we conducted a randomized trial of the safety and efficacy of gabapentin for RIM-associated pain during CRT.

Methods: HNC patients (pts) receiving CRT were randomized to standard pain control (SPC) with acetaminophen and opioids, or SPC plus gabapentin (SPC+G). Gabapentin was maintained at 900mg/day for 4 weeks after CRT. Primary endpoint was maximum visual analogue scale (VAS) score during CRT, and secondary endpoints were total opioid dose, changes in QOL (EORTC QLQ-C30 and QLQ-HN 35) from baseline to 4 weeks after CRT, and adverse events.

Results: Twenty-two eligible Stage III or IV pts were randomly assigned to SPC or SPC+G (n=11 each). Twelve were treated in a locally advanced setting and 10 in a postoperative setting. Median maximum VAS scores, median total dose of opioids at maximum VAS and total dose of opioids at 4 weeks after CRT tended to be higher in the SPC+G arm (47 in SPC vs. 74 in SPC+G, p=0.517; 215mg vs. 745.3mg, p=0.880; and 1260mg vs. 1537.5mg, p=0.9438, respectively), without significance. QOL analysis showed significantly worse scores in the SPC+G arm for weight gain (p=0.005). Adverse events related to gabapentin were manageable.

Conclusions: This pilot study is the first prospective randomized trial of gabapentin for RIM-related pain. Gabapentin had no apparent beneficial effect. Further research into agents for RIM-related pain is warranted.

Keywords: Chemoradiotherapy; Gabapentin; Head and neck cancer; Radiation-induced mucositis.