Effectiveness of adjunctive analgesics in head and neck cancer patients receiving curative (chemo-) radiotherapy: A systematic review.

OBJECTIVE: Our aim was to give an overview of the effectiveness of adjunctive analgesics in head and neck cancer (HNC) patients receiving (chemo-) radiotherapy. DESIGN: Systematic review. INTERVENTIONS: This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Embase, Web of Science, the Cochrane Library, and ClinicalTrials.gov were searched for studies concerning "head neck cancer," "adjunctive analgesics," "pain," and "radiotherapy." OUTCOME MEASURES: Pain outcome, adverse events, and toxicity and other reported outcomes, for example, mucositis, quality of life, depression, etc. RESULTS: Nine studies were included in our synthesis. Most studies were of low quality and had a high risk of bias on several domains of the Cochrane Collaboration tool. Only two studies comprised high-quality randomized controlled trials in which pregabalin and a doxepin rinse showed their effectiveness for the treatment of neuropathic pain and pain from oral mucositis, respectively, in HNC patients receiving (chemo-) radiotherapy. CONCLUSIONS: More high-quality trials are necessary to provide clear evidence on the effectiveness of adjunctive analgesics in the treatment of HNC (chemo-) radiation-induced pain.