The left subcostal area includes the spleen, the side of the greater curvature of the stomach, the splenic flexure of the transverse colon, as well as the adrenal glands, kidneys, and part of the omentum of the small intestine. If there is pain and discomfort under the left side of the ribs, there is a possibility of splenic rupture, which manifests as acute abdominal pain, usually located on the left side of the rib arch, under the left rib margin. If there is a lot of intra-abdominal bleeding, the patient may show hemorrhagic shock, accelerated heart rate, lowered blood pressure, and non-coagulated blood can be extracted by emergency abdominal puncture, or when abdominal CT is performed, splenic peritoneal laceration and splenic rupture can be found, and so on. It is necessary to perform an emergency caesarean section to remove the spleen, and at the same time, blood transfusion and other resuscitation are needed. If the tumor of transverse colon and splenic flexure can also be manifested as pain in the left upper abdomen, hidden pain, accompanied by increased frequency of stools, blood in stools and black stools, etc., colonoscopy can be performed to further clarify the situation, and radical tumor surgery can be performed after clarification.