A case of pancreatic intraepithelial neoplasia detected by pancreatic duct dilation

A male patient in his 30s was referred to our institution for a detailed checkup of the dilation of the tail of the main pancreatic duct. Through endoscopic ultrasonography, stenosis of the main pancreatic duct in the body of pancreas was shown. ERP with brush cytology was also carried out from the stenosis and pancreatic juice cytology which showed atypical cells (Papanicolaou Class IIIa). Due to the possibility of the tumor being developed into pancreatic cancer, with the patient's consent, surgical treatment was performed. Through Laparoscopic middle pancreatectomy, the final pathological diagnosis was the low-grade pancreatic intraepithelial neoplasia (PanIN) with localized pancreatitis. We experienced a case of localized pancreatitis caused by stenosis and obstruction of the origin of the bifurcated pancreatic duct owing to PanIN, which resulted in narrowing of the main pancreatic duct owing to fibrosis associated with pancreatitis.