The yellow color of the mouth may be caused by jaundice, not necessarily cancer. In addition to causing a yellow color in the mouth, jaundice can also cause yellowing of the sclera, or the whites of the eyes, as the common people call it. There are many different causes of jaundice, the most common being liver disease, including various types of hepatitis and cirrhosis. In addition, hemolytic diseases can also cause yellowing of the oral mucosa and sclera, such as acute hemolytic anemia and sericosis. Of course, many cancers can also cause jaundice, the most common being liver cancer and pancreatic cancer. Malignant tumors from other parts of the body that metastasize to the liver and pancreas may also cause yellow staining of the mucous membranes. There is also a special condition called physiological jaundice that may occur when eating large amounts of food containing yellow pigments, such as oranges and mangoes. Therefore, when the oral mucosa is yellow in color, it is not necessarily cancer, but benign diseases or even normal conditions may also occur, so it is important to identify them carefully and it is best to go to the hospital.