What's New in the Adrenal Medulla?

Roderick Clifton-BlighAustralia Speaker What's New in the Adrenal Medulla?Phaeochromocytomas (PCs) are adrenal chromaffin cell tumours; paragangliomas (PGLs) are derived either from parasympathetic paraganglia of the skull base and neck (HNPGLs: glomus caroticum, jugulare, tympanicum and vagale) and anterior/middle mediastinum, or from sympathetic-associated chromaffin paraganglia in the abdomen, pelvis and (rarely) the posterior mediastinum. PCs and PGLs (collectively, PPGLs) present in myriad ways, often dependent upon their specific genetic alteration (either germline or somatic). This talk will highlight many recent advances in diagnosis and treatment of PPGLs, including an update on biochemical assessment, structural and functional imaging, histology, genetics and treatment. Since there is no known prevention, early detection of tumors and surgical resection remains the only chance of cure. It follows that appropriate surveillance of patients with genetic PPGL predisposition is the most effective means to reduce morbidity and mortality in these syndromes, albeit with many potential challenges including cost, parental concern about testing children, burden of a lifetime surveillance program, and concerns about accessing insurance. Treatment of metastatic PPGL remains challenging, albeit with recent trials showing modest efficacy of multikinase inhibitors (e.g. sunitinib and cabozantinib) or HIF2-targeted therapy (belzutifan). Radionuclide therapy with either MIBG or Lutate may be appropriate for patients with slowly progressive disease. Machine-learning algorithms can now identify patients with high risk of developing metastatic disease, opening the potential for clinical trials to test efficacy of adjuvant therapies.