The smell of rotten egg in stool is not necessarily bowel cancer. The smell of rotten egg in stool is abnormal, considering that it may be caused by eating special foods or suffering from certain diseases, which may have the possibility of bowel cancer, but not necessarily caused by bowel cancer. First of all, eating certain foods may cause rotten egg smell in stool, such as rotten tofu, rotten eggs, unfresh vegetables, fruits, meat, overnight meals and other foods. Secondly, certain intestinal system diseases can also cause rotten egg smell in the stool, such as ulcerative colitis and intestinal cancer. Because these diseases lead to metabolic disorders of the digestive system, food entering the intestine cannot be digested and absorbed normally, making the stool smell like rotten eggs, so the smell of rotten eggs in stool is not necessarily intestinal cancer.