Gastric Neoplasm

Objective: To follow people with GISTs and collect tumor tissue so that it can be studied in the lab. Eligibility: People age 6 and older who have a GIST. Design: Participants will be screened with a review of their medical records and samples. Participants will enroll in 1 other NIH study, and may be asked to enroll in 2 other optional NIH studies. Participants will have a medical history and physical exam. Data about how they function in their daily activities will be obtained. Participants may speak with a genetic counselor. They may have genetic testing. Participants will give blood samples. They may have a cheek swab. For this, small brush will be rubbed against the inside of the cheek. Participants may have a computed tomography (CT) scan of the chest, abdomen, and pelvis. Or they may have a CT scan of the chest and magnetic resonance imaging (MRI) of the abdomen and pelvis. Participants will be monitored every 6-12 months at the NIH Clinical Center, for up to 10 years before having surgery. If they need surgery, it will be performed at the NIH. Then, they will be monitored every 6-12 months, for up to 5 years after surgery. If a participant has surgery, tumor tissue samples and research specimen will be taken. If a participant does not need surgery, their participation will end after 10 years. If they have surgery, the 5-year monitoring period will restart after each surgery.

This prospective randomized trial compares AI-assisted upper gastrointestinal endoscopy with high definition upper gastrointestinal endoscopy in term of missed rate of gastric neoplasm. The investigators hypothesize the miss rate of high definition upper gastrointestinal endoscopy is higher than AI-assisted upper gastrointestinal endoscopy.

The study aims to retrospectively investigate the endoscopic resection procedures of cancerous and precancerous lesions of the upper and lower digestive tract in order to evaluate the efficacy and safety outcomes and to compare different resection techniques. In particular, the resection techniques investigated will be mucosectomy, en bloc and piecemeal, endoscopic submucosal dissection (ESD) and its variants, full-thickness resection. The anatomical districts involved will be the esophagus, stomach, duodenum, colon and rectum.

Efficacy and safety of fruquintinib in combination with sintilizumab and SBRT in the treatment of oligonadenocarcinoma progression in the stomach or gastroesophageal junction

The main goal of this study is to investigate the proportion of participants with locally advanced gastric and gastroesophageal adenocarcinoma without previous treatment during the last 5 years who can tolerate all planned cycles of chemotherapy and radical surgical treatment who will be prospectively randomized into two groups to undergo one of two chemotherapy regimens, followed by surgery: 1. 8 cycles of Total Neoadjuvant ChemoTherapy (TNT) with 5-Fluorouracil (5-FU), Leucovorin, Oxaliplatin, and Docetaxel (FLOT) followed by surgery. 2. 4 cycles of Neoadjuvant FLOT chemotherapy scheme preoperatively and 4 adjuvant FLOT cycles postoperatively.

To determine the long term outcomes of Endoscopic Submucosal Dissection (ESD), Endoscopic Full Thickness Resection (EFTR) and Submucosal-Tunnelling Endoscopic Resection (STER) for upper gastrointestinal neoplastic lesions

Compared with other anti-tumor drugs, immune checkpoint inhibitors (ICIs) have their own unique pharmacokinetics (PK) and pharmacodynamics (PD), and affect patient clinical outcomes. However, at present, the data on the PK and PD characteristics of ICIs in the Chinese population are still lacking, thus further clinical trials are needed to verify them. At the same time, a large proportion of patients have no response to ICIs or the efficacy is poor, and even bring greater side effects, so it is particularly important to find effective biomarkers to predict the efficacy and adverse reactions of patients with ICIs treatment.The purpose of this study is to explore the correlation between blood concentration of Sintilimab and related predictors with efficacy and adverse reactions in patients with advanced gastric cancer so as to provide clinical reference for individualized treatment of patients with gastric cancer.