A cyst is not a tumor in the traditional sense, it is a benign condition. If it is considered a tumor, it is a benign tumor. Cysts may grow on the surface of the body or in the internal organs, for example, those that grow on the liver or kidneys are more common, that is, liver cysts and kidney cysts. Kidney cysts are divided into simple isolated kidney cysts and polycystic kidneys. The most common type of cyst that grows on the skin is the epidermoid cyst. Cysts are usually in the form of fluid in their contents. Smaller cysts do not require special treatment and usually have no obvious symptoms, and regular checkups are sufficient. If they grow quickly or are accompanied by other symptoms such as pain and discomfort, surgery may be considered. Liver cysts or kidney cysts with a diameter of less than 5cm do not require treatment, while those with a diameter of more than 5cm or accompanied by pain and discomfort can be considered for surgery or interventional treatment.