McCune Albright syndrome is a genetic predisposition to intraductal papillary and mucinous neoplasms of the pancreas associated pancreatic cancer in relation with GNAS somatic mutation - a case report.

Rationale: Intraductal papillary and mucinous neoplasms of the pancreas (IPMN) are preneoplastic lesions diagnosed with an increasing incidence. Recently, several groups have described, in up to 70% of IPMN, activating mutations of the G-protein alpha stimulatory sub-unit (Gsa subunit) gene (GNAS). GNAS-activating somatic, post-zygotic, mutations are also associated with McCune-Albright syndrome (MCAS) characterized by fibrous dysplasia, precocious puberty, and cafe-au-lait spots. Patient concerns: We herein report a patient with McCune Albright Syndrome that presented with malignant IPMN and underwent pancreatic resection. Diagnoses and interventions: Leucocyte and duodenum juice DNA analysis, endoscopically collected from secretin-stimulated pancreatic juice revealed the same (GNAS) activating mutation also found in the invasive pancreatic colloid adenocarcinoma arising from intestinal subtype IPMN. Outcomes: Thirty months after surgery, the patient was alive with recurrence (bone only metastasis). Lessons: In this observation, we show that MCAS should be view as a new genetic predisposition to IPMN associated pancreatic cancer, and consequently a targeted screening in this high-risk population might be proposed.