[Curative endoscopic therapy: which lesions can be addressed]

Since the implementation of a nationwide screening colonoscopy the incidence of colorectal adenocarcinoma is decreasing, while the amount of early endoscopically resectable tumours is increasing. Similarly malignant tumors of the upper gastrointestinal tract are diagnosed and resected endoscopically more often. In part, this also depends on improvements in technology.The current guidelines of diagnosis and treatment of squamous carcinoma and adenocarcinoma of the esophagus, gastric cancer and colorectal cancer exactly define, which lesions can be endoscopically resected curatively. This mostly depends on the risc of metastases in regional lymph nodes. The risc of a lymphatic spread can be asessed by histopathological characteristics depending on the localisation of the lesion. Substantially, these characteristics comprise the depth of invasion in the resection specimen and the status at the resection margins after the endoscopic resection as well as the tumor subtype and the histological grading of the tumor. In addition, an infiltration in lymphatic or blood vessels has to be taken into account.