SLC6A2 and pheochromocytoma: Meta-[18F]fluorobenzylguanidine ([18F]mFBG) PET-CT is a novel imaging modality for norepinephrine transporter-expressing tumours, such as neuroblastoma and phaeochromocytoma, enabling quantitative assessment and improved diagnostic accuracy compared to meta-[123I]iodobenzylguanidine ([123I]mIBG) scintigraphy.