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Accurate detection of genomic alterations using high-throughput sequencing is an essential component of precision cancer medicine. We characterize the variant allele fractions (VAFs) of somatic single nucleotide variants and indels across 5095 clinical samples profiled using a custom panel, CancerSCAN. Our results demonstrate that a significant fraction of clinically actionable variants have low VAFs, often due to low tumor purity and treatment-induced mutations. The percentages of mutations und

HGD and ductal dilatation are significant predictors of malignancy in ampullary adenomas. When these risk factors are present, precautions should be taken in the consideration of malignancy in patients with ampullary adenoma.

BACKGROUND/AIMS: Initial proton pump inhibitor (PPI)-based triple therapy for Helicobacter pylori (H. pylori) infection is less effective in patients with nonulcer dyspepsia (NUD) than those with peptic ulcer disease (PUD). To date, there have been no studies on the difference in eradication rates in NUD compared to PUD with regard to second-line therapy. Therefore, we retrospectively analyzed the difference in eradication rates of a second-line quadruple therapy for NUD and PUD patients. METHOD

The 2010 World Health Organization classification of neuroendocrine carcinoma G3 was the only factor related to poor prognosis in patients with biliary neuroendocrine neoplasms.

Background/Aims: Controversy remains over the optimal approach to preoperative biliary drainage in patients with resectable perihilar cholangiocarcinoma. We compared the clinical outcomes of endoscopic biliary drainage (EBD) with those of percutaneous transhepatic biliary drainage (PTBD) in patients undergoing preoperative biliary drainage for perihilar cholangiocarcinoma. Methods: A total of 106 consecutive patients who underwent biliary drainage before surgical treatment were divided into two

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) are commonly used diagnostic modalities in biliary strictures. We compared the diagnostic yield of EUS and ERCP-based tissue sampling in intrinsic biliary strictures without extrinsic mass outside the bile duct. METHODS: A total of 85 patients who underwent ERCP and EUS for diagnosis of suspected biliary strictures confined to the bile duct were analyzed retrospectively at Samsung Medical Center, Se

Background/Aims: Several precut techniques have been used to gain biliary access for difficult cases. The aim of this study was to evaluate the success and complication rates of two precut techniques, transpancreatic septotomy (TPS) and needle knife infundibulotomy (NKI), in difficult biliary cannulation due to the presence of unintended pancreatic cannulation. Methods: Eighty-six patients who failed standard biliary cannulation were included. TPS was performed when we failed to achieve biliary

Background/Aims: The objective of this study was to investigate the value of cyst fluid carcinoembryonic antigen (CEA) in combination with cytology and viscosity for the differential diagnosis of pancreatic cysts. Methods: We retrospectively reviewed our data for patients who underwent endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and cyst fluid analysis. We investigated the sensitivity, specificity and accuracy of the combination of cyst fluid CEA, cytology and viscosity testing

A 21-year-old man admitted complaining of sudden severe epigastric pain for 1 day. He had been diagnosed as ulcerative colitis (UC) and taking mesalazine for two months. UC was in nearly complete remission at admission. He never drank an alcohol, and serum amylase was 377 IU/L. CT scan showed inferior vena cava (IVC) thrombosis in addition to mild acute pancreatitis. To evaluate the cause of acute pancreatitis and IVC thrombosis, magnetic resonance cholangiopancreatogram (MRCP), endoscopic ultra

Health screening is somewhat helpful for improving the curative resection rate and median survival of patients with pancreatic cancer detected by screening tests. However, the benefit of this method in improving long-term survival is limited by how early the cancer is detected.

The technical advances in endoscopic ultrasonograpy (EUS) and accessories have enabled performing EUS-guided intervention in the pancreas and biliary tract. Many research centers have been performing or investigating EUS-guided drainage, EUS-guided celiac plexus neurolysis and block, EUS-guided anastomosis that includes choledocho-enterostomy and choledocho-gastrostomy, EUS-guided ablation and injection therapy mainly for pancreatic neoplasm, EUS-guided photodynamic therapy and EUS-guided brachy