Hotspots of Somatic Genetic Variation in Pituitary Neuroendocrine Tumors.

The most common genetic drivers of pituitary neuroendocrine tumors (PitNETs) lie within mutational hotspots, which are genomic regions where variants tend to cluster. Some of these hotspot defects are unique to PitNETs, while others are associated with additional neoplasms. Hotspot variants in and are the most common genetic causes of acromegaly and Cushing's disease, respectively. Although it has been proposed that these genetic defects could define specific clinical phenotypes, results are highly variable among studies. In contrast, hotspot variants are associated with a familial syndrome of cancer predisposition, and only exceptionally occur as somatic changes. A small number of non--driven corticotropinomas are due to somatic hotspot variants in or ; the latter is a well-known mutational hotspot in cancer. Finally, somatic variants affecting a hotspot in have been associated with multiple cancers and, more recently, with prolactinomas. Since the associations of , , and hotspot variants with PitNETs are very recent, their effects on clinical phenotypes are still unknown. Further research is required to fully define the role of these genetic defects as disease biomarkers and therapeutic targets.