{"type":"rich","version":"1.0","provider_name":"Transistor","provider_url":"https://transistor.fm","author_name":"Board Pearls","title":"Chapter 7, Ep 2 of 2: Gastric Tumors MALT NET GIST","html":"<iframe width=\"100%\" height=\"180\" frameborder=\"no\" scrolling=\"no\" seamless src=\"https://share.transistor.fm/e/3983958f\"></iframe>","width":"100%","height":180,"duration":1007,"description":"Episode two of the Gastritis and Gastric Cancers chapter works through the four gastric tumor families where histology and molecular driver are the discriminator: adenocarcinoma by Lauren type, MALT versus large B-cell lymphoma, the three gastric neuroendocrine tumors, and GIST as the model targeted-therapy cancer. Each tumor's biology drives its staging and its drug. Board-relevant triggers, molecular markers, and treatment sequences throughout.\n \nTopics covered\n\nGastric adenocarcinoma and the Lauren classification\nHereditary diffuse gastric cancer and CDH1\nAdenocarcinoma staging and molecular profiling\nMALT versus large B-cell gastric lymphoma\nThree types of gastric neuroendocrine tumor\nGIST molecular biology and risk stratification\nTargeted therapy sequences (FLOT, R-CHOP, TKIs)\n \n \nKey decisions\n\nIntestinal-type adenocarcinoma arises from the H. pylori atrophy cascade; diffuse type comes from E-cadherin/CDH1 loss, signet-ring cells, and worse prognosis. Signet-ring histology in a 30s-40s patient with a first-degree relative triggers germline CDH1 testing and prophylactic total gastrectomy.\nLinitis plastica gives a rigid non-distensible leather-bottle stomach; superficial forceps biopsies miss it because cells sit deep, so non-diagnostic superficial biopsies mandate deeper sampling. Resectable disease gets perioperative FLOT plus D2 dissection; metastatic disease is profiled for HER2, PD-L1, MMR/MSI, and claudin 18.2.\nMALT lymphoma is H. pylori-driven and eradication is curative in most early stomach-confined cases, but t(11;18) marks non-responders needing radiation or rituximab. Large B-cell lymphoma gets R-CHOP, never antibiotics alone.\nGastric NETs sort by gastrin: type 1 from atrophic gastritis (high gastrin, high pH), type 2 from ZES/MEN1 (high gastrin, low pH), both low-risk; type 3 is gastrin-independent on normal mucosa with normal gastrin and is the dangerous one, resected like adenocarcinoma. A normal gastrin flags the highest-risk NET.\nGIST arises...","thumbnail_url":"https://img.transistorcdn.com/-FuAdDBcPDLhEoUmroZKtOBRvuBn_FHPpYlh41hOnU4/rs:fill:0:0:1/w:400/h:400/q:60/mb:500000/aHR0cHM6Ly9pbWct/dXBsb2FkLXByb2R1/Y3Rpb24udHJhbnNp/c3Rvci5mbS9iNzlh/ZTU4Y2MzNWExMjQ5/MjA5OWMwMmI3ZTk5/NGFiZS5wbmc.webp","thumbnail_width":300,"thumbnail_height":300}