Endocrine Abstracts

Background: Pheochromocytomas and paragangliomas (PPGLs) are rare, often catecholamine-secreting tumours with unpredictable malignant potential and risk of late recurrence. We hereby highlight three cases with variable progression under ongoing care at University Hospitals Derby & Burton NHS Trust.

Case Series: Case 1: A 32-year-old man with Von Hippel–Lindau (VHL) syndrome who developed bilateral adrenal pheochromocytomas requiring adrenalectomy in 2012, over the next decade went blind due to ocular hemangioblastomas, had treatment for renal cell carcinoma, and resection of a spermatic cord paraganglioma. Surveillance imaging in 2024 highlighted a new retrohilar paraganglioma, with elevated plasma normetadrenaline (1,600 pmol/l). Surgical resection at Derby is planned, but it prompted discussion about belzutifan therapy with Sheffield NET MDT. Case 2: A 72-year-old man presented with collapse with a 12 cm adrenal pheochromocytoma. Following resection, metanephrines remained markedly raised (8,620 pmol/l) and histology was suggestive of malignancy (PASS= 7). Within a year, MIBG scintigraphy surveillance demonstrated residual adrenal bed disease and new skeletal metastases. Following discussion with Birmingham NET MDT, therapeutic MIBG in Sheffield (Aug 2023–Feb 2024) led to radiological stability and continued under regular imaging surveillance at Derby. Case 3: A 72-year-old man post adrenalectomy in 2015 showed rising Normetanephrines from 2019 that prompted SPECT/CT MIBG, Octreotide scan that were all negative until Ga-68 DOTATATE PET identified multifocal nodal disease. A conservative approach with potential radiotherapy at Derby was decided via Birmingham NET MDT.

Learning Points: PPGLs may recur years after curative surgery, even with “low-risk” histology. Persistent biochemical–radiological discordance warrants Ga-68 DOTATATE PET. VHL-associated disease highlights multisystem burden and the promise of HIF-2α inhibitors (belzutifan). Access to regional facilities i.e. Ga-68 DOTATATE PET & MIBG therapy and collaborative MDT’s is crucial for enabling high quality local patient care without clogging up tertiary services with routine investigations and appointments.