Prospective case series of neuropathic cancer pain in patients treated with an EGFR-inhibitor.

Abstract

Novel treatments of neuropathic pain are urgently needed. Rapid relief of neuropathic cancer pain in patients treated with epidermal growth factor receptor (EGFR) inhibitors have been reported. Experiments in rodent models confirm the pain relief and reveal novel mechanisms critically involving the EGFR. Clinical pain research is complicated and patients with advanced cancer are heterogeneous, often with complex, deteriorating clinical pictures, hampering feasibility of drug-trial procedures. Prospective case series exploring the EGFR inhibition/neuropathic cancer pain association in order to inform planning clinical trials. Symptom assessment method was tailored to what was ethical, feasible, and clinically relevant for each patient. Patients with neuropathic cancer pain treated off-label with the monoclonal antibody panitumumab were studied to assess feasibility of different measurement tools. Fourteen of 20 patients (70%) experienced clinically significant pain relief. There was good concordance in patient and physician-reported outcomes. Results support panitumumab's potential to be of significant benefit to patients with refractory neuropathic cancer pain. Findings also reinforce the difficulty of using conventional drug trial endpoints and designs in this population. Innovative research methods must be considered for much needed pivotal trials.