A case of complex inferior limb pain treated with intrathecal betamethasone and intravenous glycerin; importance of comprehensive pain evaluation
Abstract
A 63-year-old man underwent right colon resection for cecal cancer following chemotherapy, followed by radiation therapy to the lung, liver and ischial bone metastases. He gradually developed right lower limb pain with numbness and his walking was affected markedly. He was admitted to the palliative care unit at our hospital for symptom management. Initially, we reasoned that the pain with numbness was caused by the cancerous invasion within the vertebral canal at S1, but oral oxycodone administration did not provide symptom relief. With the patient’s consent, we administered 4 mg of betamethasone in the subarachnoid space.1,2 after which the patient could walk with a walker. However, the walking instability with lower limb pain and numbness returned 2 weeks later. A second dose of subarachnoid betamethasone 4 mg was not fully effective. Due to development of a slight cognitive disorder, we performed brain magnetic resonance imaging, which revealed a 4×5 cm metastasis in his left frontal lobe. Ten doses of 3 Gy radiation and 40g daily of intravenous glycerin administration relieved his pain and resolved the motor disability. After this treatment, he could walk without walker and was discharged from our hospital. With daily intravenous glycerin administration and oral betamethasone, he could go traveling or to fitness center for about 1 month after discharge. Then he developed respiratory difficulty which was associated with extensive invasion of lung metastases, and intermittent or continuous sedation was added with his consent. He did not suffer the lower limb pain with numbness to when he died after 5 weeks after discharge.
In the present case, the two cancer metastases, in the vertebral canal and brain were thought to have caused the lower limb pain with numbness. A comprehensive pain evaluation is important for cases involving complex cancer pain with numbness.3,4
