Botulinum Toxin Type A Injection for Neuropathic Pain in a Patient With a Brain Tumor: A Case Report.

Neuropathic pain is usually managed pharmacologically, rather than with botulinum toxin type A (BTX-A). However, medications commonly fail to relieve pain effectively or have intolerable side effects. We present the case of a 62-year-old man diagnosed with an intracranial chondrosarcoma, which was removed surgically and treated with radiation therapy. He suffered from neuropathic pain despite combined pharmacological therapy with gabapentin, amitriptyline, tramadol, diazepam, and duloxetine because of adverse effects. BTX-A (100 units) was injected subcutaneously in the most painful area in the posterior left thigh. Immediately after the injection, his pain decreased significantly from 6/10 to 2/10 on a visual analogue scale. Pain relief lasted for 12 weeks. This case report describes intractable neuropathic pain caused by a brain tumor that was treated with subcutaneous BTX-A, which is a useful addition for the management of neuropathic pain related to a brain tumor.