LAUSR

A 68-year-old male with a history of nephrotic syndrome was referred to our hospital for treatment of recurrent pancreatitis and infectious peripancreatic fluid collection (PFC) in the tail of the pancreas. Contrast-enhanced CT showed multiple PFC on the dorsal side of the stomach and around the kidney (Fig. 1a). As the patient did not respond to treatment with percutaneous drainage and antibiotics, we initially performed endoscopic ultrasound (EUS), which revealed no pancreatic duct lesion/mass. Subsequently, we implemented EUS-guided drainage of PFC via the stomach (Fig. 1b) and endoscopic retrograde pancreatography (ERP) for evaluating the pancreatic duct. ERP revealed the stenosis and disruption of the main pancreatic duct (MPD) in the pancreatic tail (Fig. 1c). Since pancreatic juice cytology via an endoscopic nasal drainage tube placed across the stenosis of the MPD revealed atypical cells (Fig. 1d), we diagnosed the stenosis as intraepithelial neoplasia, and performed distal pancreatectomy. Pathological analysis of the resected specimen revealed high-grade pancreatic intraepithelial neoplasia consistent with the stenosis of the MPD and disruption of the caudal adjacent MPD (Fig. 2). The patient has developed no recurrence of cancer for 12 months after surgery. Although there have been some reports of obstructive pancreatitis caused by advanced pancreatic cancer, elevated serum pancreatic enzymes and pancreatitis-related symptoms are less likely to occur in early stage pancreatic cancer. Furthermore, as pancreatic fistula is often caused by postoperative morbidly or pancreatitis, coexistence of early pancreatic cancer and pancreatic fistula is extremely rare. However, when EUS to be initially performed for evaluating the pancreas reveals no lesion/mass in the case with recurrent pancreatitis/refractory PFC, early-phase ERP should be performed for the evaluation of the MPD and cytological diagnosis considering intraepithelial neoplasia.