Peripheral and Neuraxial Chemical Neurolysis for the Management of Intractable Lower Extremity Pain in a Patient with Terminal Cancer

Abstract

We present the case of a 74-year-old man with Stage IV metastatic, multifocal, malignant fibrous histiocytoma (T2b, N1, M1, G4) invading the proximal area of the left lower extremity and resulting in intractable neuropathic pain along the distribution of the femoral nerve. He described the pain as being so severe to cause inability to ambulate without assistance or to sleep in a supine or prone position. After a spinal cord stimulation trial and a trial of intrathecal (IT) hydromorphone, both performed at an outside institution, had failed to achieve adequate pain relief, we decided to perform a femoral nerve chemical neurolysis with phenol under ultrasound (US) guidance. The intervention provided 6 months of almost complete pain relief. With the tumor spreading in girth distally and proximally to the scrotal and pelvic areas as well as to the lungs, and pain returning back to baseline, we proceeded with a second femoral nerve chemical neurolysis. Unfortunately we were not able to achieve adequate pain relief. Therefore we opted to proceed with a diagnostic injection of local anesthetic under fluoroscopic guidance at the left L2, L3, and L4 nerve roots level. This intervention provided 100% pain relief and was followed, a few days later, by chemical neurolysis with phenol 3%. The patient reported complete pain relief with the procedure and no sensory-motor related side effects or complications. He was able to enjoy the last 6 weeks of life with his wife and family, pain-free. With this report we add to the limited literature available regarding the management of intractable cancer pain with chemical neurolysis in and around the epidural space. Key words: Cancer, pain, chemical neurolysis, peripheral, neuraxial