Approach to the Management of Gastrointestinal Manifestations in Patients With Phaeochromocytoma and Paraganglioma.

Objective: Managing gastrointestinal symptoms in patients with phaeochromocytoma and paraganglioma (PPGL) is challenging due to the risk of catecholaminergic crisis with many commonly prescribed medications, especially in functional tumours. We reviewed gastrointestinal symptom management and outcomes in PPGL patients at our centre and developed recommendations based on a literature review and our experience.

Design, patients, measurement: A single-centre retrospective analysis of the management of gastrointestinal symptoms in patients with PPGL between 2019 and 2024 was completed. A literature review of gastrointestinal manifestations in PPGL was undertaken.

Results: Twenty-four individuals with PPGL admitted for radionuclide therapy, chemotherapy, surgery or other medical illness were included. Eighteen (75%) had metastatic disease. Fifty administration events of antiemetics for nausea or vomiting occurred. Two patients had acute colonic pseudo-obstruction. Dopamine antagonists (metoclopramide) and corticosteroids (dexamethasone) were administered to 10 and 9 patients, respectively, the majority of whom were alpha-blocked (n = 7) or had a dopaminergic/biochemically silent phenotype (n = 10). A patient with noradrenergic PPGL experienced a hypertensive episode following high-dose dexamethasone. No patients with biochemically negative/dopaminergic phenotypes or on alpha blockade experienced an antiemetic-related adverse event. Published evidence of dopamine antagonists and corticosteroids precipitating catecholaminergic crisis was mostly limited to case reports. While low-risk antiemetics (serotonin, histamine or neurokinin antagonists) are preferable, we found higher-risk antiemetics (dexamethasone and metoclopramide) can be cautiously administered in patients with a biochemically negative/dopaminergic phenotype or in those on adequate alpha blockade. Limited case reports demonstrated anti-cholinergic agents were beneficial for the management of acute colonic pseudo-obstruction.

Conclusions: Optimal management of gastrointestinal symptoms in PPGL should consider disease characteristics such as primary location, secretory profile, alpha blockade and medication profile.