Efficacy and safety of pancreatic juice cytology by using synthetic secretin in the diagnosis of pancreatic ductal adenocarcinoma

BACKGROUND AND AIM: Pancreatic ductal adenocarcinoma (PDAC) is difficult to detect in its early stages with the poorest prognosis of all cancers. To improve the prognosis, a precise diagnosis is needed when we suspect PDAC. Although endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNA) is a widely accepted modality for the diagnosis of PDAC, its sensitivity is 85-89%, and approximately 10% of PDAC cases cannot be diagnosed. The main causes that interrupt the diagnosis of PDAC by using EUS-FNA are tumor size, presence of a vessel or the main pancreatic duct along the puncture route, and difficulty in withdrawing anticoagulant. Pancreatic juice cytology (PJC), the sensitivity of which is 33.3-65.8%, is a method for the diagnosis of PDAC cases in which carrying out of EUS-FNA is difficult. To diagnose PDAC appropriately, we need to improve the diagnostic ability of PJC. METHODS: We examined PJC using synthetic secretin for 138 cases of pancreatic tumor and pancreatic non-cancerous diseases. RESULTS: Sensitivity of PJC improved from 50.9% to 74.0% as a result of synthetic secretin loading, and 13 PDAC cases that had not been able to be diagnosed with EUS-FNA could be diagnosed pathologically by PJC. Although there were 12 patients with mild pancreatitis (8.7%) as a complication, all were relieved with conservative treatment. CONCLUSION: Adding synthetic secretin to PJC is useful for cases in which it is difficult to carry out EUS-FNA for PDAC.