A systematic review of orofacial pain in patients receiving cancer therapy

We present the findings of a structured systematic review of the literature assessing orofacial pain induced by malignant disease and/or its therapy (excluding mucositis). This evaluation of the literature published after the 1989 NIH Development Consensus conference on the oral complications of cancer therapies is an effort to assess the prevalence of pain, quality of life and economic impact, and management strategies for cancer therapy-induced orofacial pain. A systematic medical literature search was conducted with assistance from a research librarian in MEDLINE/PubMed and EMBASE databases for articles published between January 1, 1990 and December 31, 2008. Each study was independently assessed by two reviewers with expertise in the field of oral oncology. Thirty-nine studies assessed pain in the head and neck region. The measure was commonly embedded in quality of life studies. Most of these studies described pain in head and neck cancer (HNC) patients, which therefore became the focus of the report. Pain is common in patients with HNC and is reported by approximately half of patients prior to cancer therapy, 81% during therapy, 70% at the end of therapy, and by 36% at 6 months after treatment. Pain is experienced beyond the 6-month period by approximately one third of patients and is typically more severe than pre-treatment cancer-induced pain. This systematic review identified the presence of pain before cancer therapy, likely attributable to the cancer; an increase in pain during therapy and the common persistence of pain following cancer treatment. Continuing research should use validated tools to prospectively assess orofacial pain, its causes and pathophysiology, and its effect on quality of life and economic impact. Clinical trials of pain management in this setting are also warranted.