Successful analgesic treatment with continuous sacral epidural ethanol injection therapy for anal pain caused by multiple metastases of malignant pheochromocytoma.

Background: Anal and perineum pain caused by malignant tumor invasion is often difficult to control with opioids. Continuous sacral epidural ethanol injection therapy is less likely to cause bladder and rectal disturbances, making it a suitable treatment option for patients with preserved voiding function.

Case presentation: A 45-year-old woman with multiple metastases of malignant pheochromocytoma suffered severe anal pain that worsened, especially when sitting, and was unresponsive to opioid rescue therapy. With her NRS score of 9, a sacral epidural catheter was placed, and a continuous infusion of 2% lidocaine was administered overnight. This is followed by a 1.5mL bolus of ethanol and continuous ethanol administration at 2 mL/h. After administration, her anal pain decreased to approximately NRS 0-1, and she was subsequently discharged.

Conclusion: We report successful pain control using continuous sacral epidural ethanol injection therapy in a patient with anal pain due to malignant pheochromocytoma metastasis.