• Cancer
• Pain
• Drug administration
• Pharmacology

Neuropathic pain due to advanced malignancy can be challenging to manage. Here, we present a case in which sodium valproate was added to a multimodal analgesic regimen to manage severe pain in a patient with advanced malignancy.

The patient had a diagnosis of metastatic de-differentiated liposarcoma with disease affecting the retroperitoneum, liver and left tibia. The patient presented to the acute oncology service with a pain crisis and fever. The pain radiated from the lumbar region bilaterally to the perineum and knees. It was lancinating in nature and triggered by the slightest movement of the back or legs. Once triggered, the intense pain would last 2–5 min, with a more persistent dull pain lasting 20–30 min. At its worst, the pain was overwhelming, causing the patient to call out in pain and become flushed and clammy. At one point, the patient required Entonox to enable a transfer from a porter’s trolley to the hospital bed.

A CT scan demonstrated a central necrotic retroperitoneal mass encompassing the aorta, vena cava and left psoas muscle, with progressive destructive collapse of the L4 vertebra and cortical destruction of the L3 vertebra with soft tissue extending into the spinal canal. Also, there was a fluid collection in the left iliacus and iliopsoas. MRI 2 weeks prior had demonstrated features highly suspicious for …