五种水果去除体内寒气.pptVIP

Environmental factors Environmental factors Genetic factors The majority of gastric tumor are sporadic in nature There are rare inherited gastric cancer predisposition traits such as germline p53 (Li-Fraumeni syndrome) E-cadherin (CDH1) alterations in diffuse gastric cancers Precancerous changes Precancerous lesions Defined as those pathological changes predisposed to gastric cancer dysplasia 10% of patients may progress in severity majority of patients either regress or remain stable High-grade dysplasia may be only a transient phase in the progression to gastric cancer occurs in atrophic gastritis or intestinal metaplasia Nature history of gastric dysplasia Precancerous condition Defined as those clinical setting with higher risk of developing gastric cancer Chronic atrophic gastritis Gastrectomy Pernicious anemia Menetrier’s disease Chronic gastric ulcer Gastric polyps Postulated sequence of histologic events in the progression to gastric adenocarcinoma and potential contributory factors Pathology Stages Early stage limited in the mucosa and submucosa layers, no matter with or without lymph node metastasis Classified by the Japanese Society for Gastric Cancer 1cm 0.5cm Advanced stage invaded over submucosa According to Bormann’ classification TNM classification (UICC) Morphology---early stage Morphology---early stage Morphology---early stage Morphology ---advanced stage Pathohistologic classification Histology Adenocarcinoma 90% Lymphoma 5% Stromal 2% Carcinoid 1% Metastasis 1% Adenosquamous/squamous 1% Miscellaneous 1% Origin (Lauren) Intestinal type associated with most environmental risk factors carries a better prognosis shows no familial histor