In particular, 12 NETs (all of which categorized as SOM-NETs and three of which with double, synchronous tumors involving both the major and minor ampulla) were NF1-associated, two NETs were MEN1-associated, whereas one NEC arose in the setting of classic MEN2A syndrome (in a patient with a history of medullary thyroid carcinoma and primary hyperparathyroidism). This evidence concerns the gene NF1 and neuroendocrine carcinoma.