There are several types of gastric cancer.

According to the pathological classification of gastric cancer, gastric cancer can be divided into adenocarcinoma, signet ring cell carcinoma, adenosquamous carcinoma, medullary carcinoma and undifferentiated cell carcinoma. Gastric adenocarcinoma is caused by malignant transformation of gastric glandular body cells; signet ring cell carcinoma is a mucinous adenocarcinoma originating from glandular epithelial cells; adenosquamous carcinoma is a malignant tumor arising from ectopic squamous epithelium; medullary carcinoma is a tumor in which cancer cells are arranged into solid pieces or cords under a microscope, with relatively little interstitial fibrous tissue. Undifferentiated cell carcinoma refers to the undifferentiated state of cancer cells, so it is called undifferentiated cell carcinoma.