MEN1 and multiple endocrine neoplasia type 1: The search for relevant original publications and case reports written in English was performed on PubMed, Embase, Scopus, and Google Scholar using the NCI Dictionary of Cancer Terms: multiple endocrine neoplasia type 1 OR MEN1 AND phenotype OR genotype, multiple endocrine neoplasia type 1 OR MEN1 AND genotype-phenotype correlation, multiple endocrine neoplasia type 1 OR MEN1 AND aggressive, multiple endocrine neoplasia type 1 OR MEN1 AND aberrant.