It is generally a sporadic tumour, even though it can be also part of a hereditary syndrome including the Li Fraumeni (TP53), multiple endocrine neoplasia type 1 (MEN 1), Lynch syndrome (MSH2, MLH1, PMS2, MSH6, EPCAM), Carney complex (PRKAR1A), type 1 neuro fibromatosis (MEN1), familial adenomatous polyposis coli (APC) and Beckwith–Wiedeman (IGF2 locus) [2]. Here, PMS2 is linked to multiple endocrine neoplasia type 1.