The American Journal of Gastroenterology is published by Nature Publishing Group (NPG) on behalf of the American College of Gastroenterology (ACG). Ranked the #1 clinical journal covering gastroenterology and hepatology*, The American Journal of Gastroenterology (AJG) provides practical and professional support for clinicians dealing with the gastroenterological disorders seen most often in patients. Published with practicing clinicians in mind, the journal aims to be easily accessible, organizing its content by topic, both online and in print. www.amjgastro.com, *2007 Journal Citation Report (Thomson Reuters, 2008)

A prospective clinical study was conducted to evaluate the safety, feasibility, and efficacy of endoscopic ultrasound (EUS)-guided choledochoduodenostomy (CDS) with direct metallic stent placement using a prototype forward-viewing echoendoscope. The indication for EUS – CDS in this study was lower biliary obstruction only, and not failed endoscopic biliary drainage, because the aim was to evaluate EUS – CDS for first-line biliary drainage therapy. The technical and functional success rates were 94 % (17 /18) and 94 % (16 /17), respectively. Early complications (focal peritonitis) were encountered in two patients (11 %). No patients developed late complications. EUS – CDS with direct metallic stent placement using a forward-viewing echoendoscope was generally feasible and effective for malignant distal biliary tract obstruction. The forward-viewing echoendoscope was useful, especially for deploying the metallic stent.

Dendritic cell (DC) therapy frequently induces a measurable immune response. However clinical responses are seen in a minority of patients, presumably due to insufficient expansion of antigen-specific cytotoxic T lymphocytes (CTLs) capable of eradicating tumor cells. To increase therapeutic efficacy of DC-based vaccination, we have undertaken the first clinical trial involving a combination therapy of gemcitabine (GEM) with immunotherapy for patients with inoperable locally advanced pancreatic cancer. Patients (n = 5) received the treatment course, which consisted of intravenous GEM administration at 1000 mg/m2 (day 1) and the endoscopic ultrasound-guided fine-needle injection of OK432-pulsed DCs into a tumor, followed by intravenous infusion of lymphokine-activated killer cells stimulated with anti-CD3 monoclonal antibody (CD3-LAKs) (day 4), at 2-week intervals. No serious treatment-related adverse events were observed during the study period. Three of the 5 patients demonstrated effective responses to this clinical trial; 1 had partial remission and 2 had long stable disease more than 6 months. In the patient with partial remission, it has been shown that DC-based vaccination combined with GEM administration induces tumor antigen-specific CTLs. This combined therapy was considered to be synergistically effective and may have a role in the therapy of pancreatic cancer for inducing tumor antigen-specific CTLs.

Both endoscopic ultrasonography (EUS)-guided choledochoduodenostomy (EUS-CDS) and EUS-guided hepaticogastrostomy (EUS-HGS) are relatively well established as alternatives to percutaneous transhepatic biliary drainage (PTBD). Both EUS-CDS and EUS-HGS have high technical and clinical success rates (more than 90%) in high-volume centers. Complications for both procedures remain high at 10%-30%. Procedures performed by endoscopists who have done fewer than 20 cases sometimes result in severe or fatal complications. When learning EUS-guided biliary drainage (EUS-BD), we recommend a mentor’s supervision during at least the first 20 cases. For inoperable malignant lower biliary obstruction, a skillful endoscopist should perform EUS-BD before EUS-guided rendezvous technique (EUS-RV) and PTBD. We should be select EUS-BD for patients having altered anatomy from malignant tumors before balloon-enteroscope-assisted endoscopic retrograde cholangiopancreatography, EUS-RV, and PTBD. If both EUS-CDS and EUS-HGS are available, we should select EUS-CDS, according to published data. EUS-BD will potentially become a first-line biliary drainage procedure in the near future.

Background There are several types of pancreatic mass, so it is important to distinguish between them before treatment. Artificial intelligence (AI) is a mathematical technique that automates learning and recognition of data patterns. This study aimed to investigate the efficacy of our AI model using endoscopic ultrasonography (EUS) images of multiple types of pancreatic mass (pancreatic ductal adenocarcinoma [PDAC], pancreatic adenosquamous carcinoma [PASC], acinar cell carcinoma [ACC], metastatic pancreatic tumor [MPT], neuroendocrine carcinoma [NEC], neuroendocrine tumor [NET], solid pseudopapillary neoplasm [SPN], chronic pancreatitis, and autoimmune pancreatitis [AIP]). Methods Patients who underwent EUS were included in this retrospective study. The included patients were divided into training, validation, and test cohorts. Using these cohorts, an AI model that can distinguish pancreatic carcinomas from noncarcinomatous pancreatic lesions was developed using a deep-learning architecture and the diagnostic performance of the AI model was evaluated. Results 22 000 images were generated from 933 patients. The area under the curve, sensitivity, specificity, and accuracy (95 %CI) of the AI model for the diagnosis of pancreatic carcinomas in the test cohort were 0.90 (0.84–0.97), 0.94 (0.88–0.98), 0.82 (0.68–0.92), and 0.91 (0.85–0.95), respectively. The per-category sensitivities (95 %CI) of each disease were PDAC 0.96 (0.90–0.99), PASC 1.00 (0.05–1.00), ACC 1.00 (0.22–1.00), MPT 0.33 (0.01–0.91), NEC 1.00 (0.22–1.00), NET 0.93 (0.66–1.00), SPN 1.00 (0.22–1.00), chronic pancreatitis 0.78 (0.52–0.94), and AIP 0.73 (0.39–0.94). Conclusions Our developed AI model can distinguish pancreatic carcinomas from noncarcinomatous pancreatic lesions, but external validation is needed.

Background and study aim: Malignancy in pancreatic neuroendocrine tumors (PNETs) is graded by assessing the resected specimens according to the World Health Organization (WHO) 2010 criteria. The feasibility of such grading using endoscopic ultrasound-guided fine-needle aspiration (EUS–FNA) specimens remains unclear. The aim of this study was to ascertain the optimal method of measuring the Ki-67 index in EUS–FNA specimens, using resected specimens as the criterion standard. Patients and methods: A total of 58 consecutive patients diagnosed with PNETs between March 1998 and May 2011 were included. The study measured intratumoral Ki-67 index heterogeneity, concordance rates of PNET grading by EUS–FNA with grade of the resected tumor, optimal method of measuring the Ki-67 index in EUS–FNA specimens, and survival analysis based on EUS–FNA specimen grading. Results: Intratumoral dispersion of Ki-67 index in resected specimens was 0.033 for Grade 1 and 0.782 for Grade 2 tumors (P < 0.001). Concordance rates for WHO classification between EUS–FNA and resected specimens were 74.0 % using the mean Ki-67 index in EUS–FNA specimens and 77.8 % using the highest Ki-67 index. The concordance rate rose to 90 % when EUS–FNA samples with less than 2000 tumor cells were excluded (26 % of EUS–FNA cases). The Kaplan–Meier survival curves were significantly stratified by the EUS–FNA grading of PNETs with 5-year survival rates of 100 %, 58.3 %, and 0 %, for Grade 1, Grade 2, and neuroendocrine carcinoma (NEC) tumors, respectively. Conclusions: Grading of PNETs by the highest Ki-67 index in EUS–FNA specimens with adequate cellularity has a high concordance with grading of resected specimens, and can predict long term patient survival with high accuracy.