Refractory postherpetic neuralgia in a multiple myeloma patient with lenalidomide maintenance therapy: a case report

Herpes zoster is not common in multiple myeloma (MM) patients treated with lenalidomide-based regimens. We report an MM patient in his late 60s who received lenalidomide as maintenance treatment and whose condition was complicated with refractory postherpetic neuralgia. The patient received antiviral treatment and analgesia immediately after the diagnosis of herpes zoster. Two months later, the patient received acupuncture, radiofrequency treatment, and even spinal cord stimulation, which failed to relieve the pain. Consequently, we performed high-resolution magnetic resonance imaging of the cervical and thoracic nerves. Then, stellate ganglion block, left C5/C6/C7/C8 nerve root block, and left thoracic 1, 2 paravertebral nerve block were performed with the assistance of real-time ultrasound. The pain was immediately relieved after treatment; however, the symptoms reappeared 2 days later. At 5 months after treatment, the patient still experienced severe pain. We suggest that MM patients complicated with postherpetic neuralgia are refractory to treatment. Starting nerve block therapy, pulsed radiofrequency, and other interventional therapies as early as possible could be a more optimal treatment plan for these patients.