Genetics and imaging of pheochromocytomas and paragangliomas: current update

AbstractPheochromocytomas (PCCs) and paragangliomas (PGLs) are rare, heterogeneous neuroendocrine neoplasms of the autonomous nervous system of chromaffin cell origin that may arise within the adrenal medulla (PCCs) or the sympathetic and parasympathetic paraganglia (PGLs). Currently referred to by the umbrella term pheochromocytomas –paragangliomas (PPGLs), these distinct tumors are characterized by specific histopathology as well as biological and clinical profiles. PPGLs may occur as part of hereditary syndromes (40% of cases) or as sporadic tumors. Currently, there are 12 different hereditary syndromes with characteristic genetic abnormalities, at least 15 well-characterized driver genes and distinct tumor metabolic pathways. Based on the Cancer Genome Atlas (TCGA) taxonomic schemata, PPGLs have been classified into three main clusters of specific genetic mutations and tumor pathways with clinical, biochemical, and p rognostic implications. Imaging plays a pivotal role in the initial diagnosis, tumor characterization, evaluation of treatment response, and long-term surveillance. While MDCT and MRI help in the anatomic localization, SPECT, and PET using different radiotracers are crucial in the functional assessm ent of these tumors. Surgery, chemotherapy, and radiotherapy are currently available treatment options for PPGLs; antiangiogenic drugs are also being used in treating metastatic disease. Evolving knowledge regarding the different genetic abnormalities involved i...
Source: Abdominal Imaging - Category: Radiology Source Type: research