The human large intestine is about 1.5 meters in length and is located from the cecum in the lower right abdomen up to the lower part of the liver, then to the left side to the lower part of the spleen, and then down the left side of the abdominal wall into the pelvis. Therefore, when lesions occur in the large intestine, they can manifest as pain in the lower right abdomen, upper right abdomen, upper middle abdomen, upper left abdomen, lower left abdomen, and pelvis of the body. The main lesions in the colon are colorectal tumors and inflammatory bowel disease, so colonoscopy is required. If lesions or masses are found, some tissues need to be removed for pathological examination. If the pathological examination confirms that it is a colon tumor, radical tumor surgery is required. If it is inflammatory bowel disease, conservative treatment can be performed in internal medicine first, and if conservative treatment is ineffective, surgery can also be considered.