Pilot study evaluating local anesthetics administered systemically for treatment of pain in patients with advanced cancer

Based on evidence that suggested that systemically administered local anesthetics might be useful in chronic pain, we initiated a pilot study to evaluate the activity and toxicity of mexiletine and flecainide in the treatment of cancer pain. Twenty-one courses of either mexiletine or flecainide were administered to patients with an Eastern Cooperative Oncology Group performance status of three or better, who were suffering from cancer pain inadequately controlled with opioid analgesics. Pain control was assessed by patient questionnaires to monitor benefit and toxicity. In 17 cases, there was no suggestion of benefit. Two cases had relatively clear- cut analgesic benefit, and two others had some suggestion of mild-to-moderate analgesic relief. Flecainide was relatively well tolerated, but mexiletine appeared to cause nausea and/or vomiting in five of eight patients. This pilot trial suggest that systemically administered local anesthetics can relieve pain in a minority of patients with cancer pain.