Palliative Symptom Management in Malignant Pheochromocytoma: Safe Use of Fentanyl and a Review of Medications Used.

Background: Pheochromocytoma is a tumor arising from adrenomedullary chromaffin cells. Five-year survival with malignant pheochromocytoma is <50%. Difficulty arises when prescribing for patients, given the potential to precipitate catecholamine crisis, a life-threatening emergency. Clinical Case: A 60-year-old woman presented with abdominal fullness and discomfort. Liver biopsy confirmed pheochromocytoma. Upper and lower abdominal pain was noted and described as "dragging" and "sharp" in nature. The Endocrine Society Clinical Practice guideline for management of pheochromocytoma recommends avoidance of morphine and codeine. Subcutaneous fentanyl was tolerated with good effect, and a continuous subcutaneous infusion was commenced. She was transitioned to a fentanyl patch and her pain was controlled. Conclusion: Symptom control in patients with pheochromocytoma remains challenging. Common opioid analgesics, dopamine-receptor antagonists, corticosteroids, and tricyclic antidepressants are medications known to precipitate a crisis. There is a lack of published research to support the safe prescribing of medications for these patients.