Recent Topics Around Multiple Endocrine Neoplasia Type 1.

Introduction: Multiple endocrine neoplasia type 1 (MEN1) is complex with regard to clinical expressions, management, and molecular pathways. Advances are being made broadly and in focused aspects. Selected topics are presented for their developments since publication of the most recent MEN1 consensus guidelines 6 years ago. Methods: Topics were selected for clinical impact or broad interest or both. For each topic, information was obtained from original reports and reviews. Results: The selected topics are as follows: tumor behavior and breast cancer in MEN1; foregut neuroectoderm tumor screening, biomarkers periodically to detect tumor emergence of foregut neuroectoderm tumors, Ga-68 dotatate positron emission tomography/computed tomography for pancreatic and duodenal neuroectodermal tumor imaging, and glucagon-like peptide-1 receptor scintigraphy for insulinoma; therapy, the size of pancreatic neuroendocrine tumor (NET) as one criterion for surgery, minimally invasive surgery of pancreatic NETs, and 177Lu dotatate therapy; MEN1 gene, the search for the MEN1/menin pathway and MEN1 or GCM2 mutation in familial isolated hyperparathyroidism, and MEN1 mutation-positive vs mutation-negative cases of MEN1 are different. Conclusions: MEN1 topics are a rich and fast-moving area. Important highlights stand out, and major and rapid advances will continue into the near future.