Studies have demonstrated that up to 17% of patients with pancreatic neuroendocrine tumours (pNETs) present pathogenic germline variants (PGVs) in several different genes, irrespective of family cancer history. Li–Fraumeni syndrome (LFS) is an autosomal dominant cancer predisposition syndrome related to PGVs in the TP53 gene. A previous case of a pNET associated with LFS (c.1009C > T, p.R337C) has been reported. Here we report the first case of a patient with pNET and TP53 p.R337H and XAF1 p.E134* germline variants, expanding the knowledge of LFS and germline mutations in neuroendocrine tumours.