Auntie Wang found that her stool had suddenly become thinner in recent days, as thin as her pinky finger. She remembered that her neighbor Auntie Liu was also found to have intestinal cancer with this symptom a while ago, so she was very scared all of a sudden and worried all day. Finally, she went to the hospital for a specialist examination. The doctor said it was caused by hemorrhoids, so Auntie Wang was relieved. I have often heard of constipation, thin stool, blood in the stool, but not many people really understand the causes of fine stool, the causes of thin stool, excluding the sudden change in diet structure or living environment, there are three main cases: hemorrhoids, rectal polyps and rectal cancer. 1, hemorrhoids hemorrhoids is a familiar disease, the incidence is also very high, there are “ten people nine hemorrhoids” said. It refers to one or more soft venous masses formed by varicose veins at the bottom of the anorectum and the mucous membrane around the anus. The main symptoms are blood in the stool, pain if there is a blood clot, and the enlargement of the hemorrhoid nucleus can lead to thinning of the stool. The bleeding hemorrhoids are caused by the bowel movement when the stool rubs the venous mass around the anus, the blood dripping down with the stool is mostly fresh blood, the blood is not mixed with the stool, and most of them do not have mucus adhesion. 2, rectal polyps Pan refers to the elevated lesions of the rectal mucosal surface protruding into the intestinal cavity, including adenomas, inflammatory polyps and polyposis. Pathologically, its content varies, some are benign tumors, some are the consequences of inflammatory hyperplasia. Blood in the stool is fresh, covered with fecal surface and does not mix with it. The polyp with a tip at the lower end of the rectum may prolapse out of the anus during defecation. When polyps are combined with ulcerative infection, there may be mucus and blood in the stool and a feeling of urgency. They are more common in people over 40 years of age. There are often no obvious symptoms in the early stage. Patients with rectal cancer often have blood and mucus in their stools, which are adherent to thick liquid, and their stool habits change, alternating between diarrhea and constipation. The frequency of stool increases, the stool is thin, and the anus is often irritated, often wanting to defecate, which is the usual phenomenon of urgency and heaviness. Patients with rectal cancer may also experience changes in systemic symptoms, such as significant weight loss and anemia in a short period of time. In clinical practice, early rectal cancer is often mistaken for hemorrhoids, thus losing the best treatment opportunity. Therefore, once there is an unexplained thinning of stool, and it continues to not return to normal, and there is no normal explanation, you should go to the hospital for examination in time. In particular, middle-aged or older patients with symptoms such as blood in the stool, something coming out of the anus, dysentery, constipation, diarrhea, thin stool, etc. and those with related family history should go to the hospital in time.