Pancreatic intraepithelial neoplasia

Pancreatic intraepithelial neoplasia (PanIN) is a precursor lesion to pancreatic ductal adenocarcinoma, but the frequency at which this transition occurs is unknown.

Epidemiology

Increasing incidence with age . Risk factors:

• obesity
• pancreatic lipomatosis

Pathology

Mostly flat lesions (occasionally papillary), consisting of varying degrees of epithelial atypia and dysplasia. They are histologically classified as low-grade or high-grade.

More commonly located in the pancreatic head .

Radiographic features

Most are <5 mm, although they may be in the 5-10 mm range.

May produce unifocal or multifocal lobulocentric pancreatic atrophy but a preoperative diagnosis of PanIN is extremely difficult as it is a microscopic lesion .