{"entity":{"id":"early-gastric-cancer","kind":"cancer","name":"Early gastric cancer","aka":["T1 gastric cancer","Intramucosal gastric cancer","Submucosal gastric cancer","Screen-detected gastric cancer"],"tldr":"Early gastric cancer has not grown beyond the submucosa, whatever the lymph nodes show. In Japan and Korea, where screening endoscopy finds most stomach cancers at this stage, many are removed through the endoscope without an operation, and the rest are cured by gastrectomy.","summary":"Early gastric cancer is defined by depth: a tumour limited to the mucosa (T1a) or submucosa (T1b), regardless of nodal spread. Its detection depends on endoscopy in people without symptoms. Korea has offered biennial endoscopic screening to everyone from age 40 in its national programme since 1999, and Japan recommended endoscopy over barium radiography in 2016; as a result more than half of gastric cancers in both countries are early, against about one in five in Europe and North America. Helicobacter pylori causes most of these cancers, and eradication after endoscopic resection roughly halves the risk of a second primary tumour in the remaining stomach.\n\nEndoscopic submucosal dissection removes the lesion in one piece with its margins. The Japanese Gastric Cancer Association criteria cover differentiated intramucosal tumours without ulceration of any size, differentiated ulcerated tumours up to 3 cm, and, after the JCOG1009/1010 trial, undifferentiated intramucosal tumours up to 2 cm without ulceration; when pathology shows deeper invasion, lymphovascular invasion or an involved margin (a high eCura risk), gastrectomy with lymph node dissection follows because the risk of nodal disease rises. Curative dissection preserves the stomach and its function with recurrence rates comparable to surgery in matched series.\n\nFor tumours outside those criteria, gastrectomy with D1+ node dissection is standard; laparoscopic distal gastrectomy proved non-inferior to open surgery for stage I disease in the Korean KLASS-01 and Japanese JCOG0912 trials and is now routine, with robotic surgery an alternative. Adjuvant chemotherapy is not given for stage I disease. Surveillance after endoscopic resection is annual endoscopy for metachronous lesions, and the whole model is being tested in Western trials of risk-based screening and in the gastric cancer arm of Lynch syndrome programmes.","asOf":"2026-09-17","wikipedia":"https://en.wikipedia.org/wiki/Stomach_cancer","links":[{"label":"Japanese gastric cancer treatment guidelines 2021 (6th edition)","url":"https://pubmed.ncbi.nlm.nih.gov/36342574/"},{"label":"JCOG1009/1010 (Gastric Cancer 2020)","url":"https://pubmed.ncbi.nlm.nih.gov/32895785/"},{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Stomach_cancer"}],"tags":["subtype-page"],"related":[],"cancers":[],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"group":"gastrointestinal","burden":"More than half of gastric cancers diagnosed in Japan and Korea, where endoscopic screening finds them, but a small minority in Western countries; five-year survival above 90 percent when the tumour is confined to the mucosa or submucosa.","subtypes":["Intramucosal (T1a) differentiated early gastric cancer (endoscopic resection)","Undifferentiated intramucosal cancer up to 2 cm (endoscopic resection after JCOG1009/1010)","Submucosal (T1b) early gastric cancer (gastrectomy)","Distal (antral) early gastric cancer, intestinal type","Screen-detected early gastric cancer (Japan and Korea)","Metachronous early gastric cancer after resection"],"biomarkers":["Depth of invasion, ulceration and size (endoscopic resection criteria)","Differentiated versus undifferentiated histology","Lymphovascular invasion and margin status on the resected specimen (eCura risk)","Helicobacter pylori status","Intestinal metaplasia and atrophy extent (Kimura-Takemoto, OLGA) for surveillance intervals"],"standardOfCare":[{"setting":"Within endoscopic criteria","approach":"Endoscopic submucosal dissection with en bloc resection and pathological assessment of depth, margins and lymphovascular invasion.","refs":["endoscopic-resection","endoscopy"]},{"setting":"Non-curative resection or outside criteria","approach":"Gastrectomy with D1+ lymph node dissection, laparoscopic or robotic (KLASS-01, JCOG0912).","refs":["gastrectomy","lymphadenectomy","robotic-surgery","jcog"]},{"setting":"After resection","approach":"Helicobacter pylori eradication and annual endoscopic surveillance for metachronous cancer; no adjuvant chemotherapy for stage I.","refs":["endoscopy","chemoprevention"]},{"setting":"Screening","approach":"Biennial endoscopy from age 40 in Korea and from 50 in Japan; risk-based screening for people of East Asian origin and with atrophic gastritis elsewhere.","refs":["screening","endoscopy"]}],"stateOfArt":["Endoscopic submucosal dissection, developed in Japan, cures the majority of early gastric cancers without removing the stomach.","Population endoscopic screening has made early-stage diagnosis the norm in Korea and Japan and is the reason their survival figures lead the world.","Helicobacter pylori eradication after resection is proven to prevent second cancers."],"history":[{"year":1962,"title":"Japanese Society of Gastroenterological Endoscopy defines early gastric cancer","refs":[]},{"year":1999,"title":"Korea launches national gastric cancer screening","refs":[]},{"year":2000,"title":"Endoscopic submucosal dissection developed in Japan","refs":["endoscopic-resection"]},{"year":2008,"title":"Fukase trial: Helicobacter pylori eradication reduces metachronous cancer after endoscopic resection","refs":[]},{"year":2016,"title":"Japan recommends endoscopic over radiographic screening; KLASS-01 supports laparoscopic gastrectomy","refs":[]},{"year":2020,"title":"JCOG1009/1010: endoscopic dissection extended to small undifferentiated tumours","refs":["jcog","endoscopic-resection"]}],"pipeline":["endoscopic-resection","robotic-surgery","liquid-biopsy","mrd-testing"],"openProblems":["Western countries have no screening and diagnose most gastric cancers late.","Predicting nodal spread in submucosal tumours to spare more patients surgery.","Artificial intelligence detection of subtle lesions is promising but not yet proven to change outcomes."],"parent":"gastric"},"route":"/cancers/early-gastric-cancer/","neighbours":{"technology":[{"id":"chemoprevention","kind":"technology","name":"Chemoprevention & risk-reducing surgery","route":"/technologies/chemoprevention/"},{"id":"endoscopic-resection","kind":"technology","name":"Endoscopic resection (EMR / ESD)","route":"/technologies/endoscopic-resection/"},{"id":"liquid-biopsy","kind":"technology","name":"Liquid biopsy (ctDNA)","route":"/technologies/liquid-biopsy/"},{"id":"mrd-testing","kind":"technology","name":"MRD / molecular residual disease testing","route":"/technologies/mrd-testing/"},{"id":"robotic-surgery","kind":"technology","name":"Robotic & minimally invasive surgery","route":"/technologies/robotic-surgery/"}],"institution":[{"id":"jcog","kind":"institution","name":"Japan Clinical Oncology Group (JCOG)","route":"/institutions/jcog/"}],"term":[{"id":"endoscopy","kind":"term","name":"Endoscopy (EGD, EUS, ERCP)","route":"/terms/endoscopy/"},{"id":"gastrectomy","kind":"term","name":"Gastrectomy","route":"/terms/gastrectomy/"},{"id":"lymphadenectomy","kind":"term","name":"Lymphadenectomy (lymph node dissection)","route":"/terms/lymphadenectomy/"},{"id":"screening","kind":"term","name":"Screening","route":"/terms/screening/"}],"cancer":[{"id":"gastric","kind":"cancer","name":"Gastric & gastro-oesophageal junction cancer","route":"/cancers/gastric/"}]}}