How to diagnose bowel cancer is an issue that most friends are concerned about. Only if we pay more attention to our physical changes in our life, we can detect the problem and seek medical consultation in time, so as to reduce the damage of bowel cancer to our body. The symptoms of bowel cancer are different in different periods. Early symptoms of bowel cancer 1.Change of normal bowel habit: diarrhea or constipation will appear alternately. At the same time, due to the stimulation of mucus and toxin secreted by tumor, it will affect the normal physiological function of intestine and change the number of stools from once a day to many times. Moreover, there is often a feeling of incomplete stool after defecation. 2.Abdominal discomfort, hidden pain or abdominal distension: Patients with colorectal cancer often have abdominal distension and abdominal pain due to intestinal dysfunction or intestinal obstruction, and the incidence of abdominal pain is higher. The pain is usually persistent, mostly concentrated in the middle and lower abdomen, with varying degrees of severity, mostly hidden pain or distension, and the tendency of gradual aggravation. 3, unexplained anemia or weight loss: often manifested as systemic symptoms, such as the appearance of unexplained anemia, fever, etc., and often accompanied by fatigue and unexplained weight loss. 4.Symptoms such as abdominal lumps: The manifestation of colorectal cancer varies from person to person. Some patients, especially some thin patients, may show symptoms such as lumps in the abdomen. At this time, patients can usually feel it by themselves. This kind of lump is usually more fixed and there is no painful feeling when touched. Second, mid-stage bowel cancer symptoms Bowel cancer is one of the malignant tumor diseases. The symptoms of early stage bowel cancer are usually not very obvious, and only reveal with the increase of tumor and further development of the disease. Therefore, those who come to the clinic with conscious symptoms are mostly middle and late stage bowel cancer cases. 1.Blood in stool Symptoms of mid-stage bowel cancer are limited to mucous membrane, which may have small symptoms or only change in bowel habit. When the tumor grows to a certain extent, blood in stool can appear, which is mostly light in color and adheres to the surface of stool. When the volume of tumor is small, because the mucous membrane is still intact, generally no bleeding will occur. As the volume increases, due to inflammation, blood transport disorder, mechanical stimulation and other reasons, mucous wax becomes erosion, ulceration, and even tumor rupture and bleeding occurs. 2.Mucus stool and pus-blood stool occur due to large amount of bacteria in the colon, secondary infection when the mucous membrane on the surface of tumor is damaged, coupled with the shedding of necrotic cells and large amount of secretion produced by the stool through stimulation and abrasion of tumor, etc. Mucus stool or pus-blood stool occurs. When bowel cancer changes, abnormal bowel performance may appear, such as loose stool, constipation, bloody stool, increased number of bowel movements, and change of stool shape, etc. Once bowel cancer enters into advanced stage, more obvious symptoms may appear, but some of them are not specific and are related to the location. 1. Right-sided colon cancer mainly manifests as indigestion, weakness, loss of appetite, diarrhea, constipation, or alternating constipation and diarrhea, abdominal distension, abdominal pain, abdominal pressure, abdominal mass, progressive anemia. The location of the mass varies with the location of the lesion. Cecum masses are located in the right lower abdomen, colon masses in the right abdomen, colon hepatic flexure masses in the right upper abdomen, and transverse colon masses near the umbilicus. In addition, there may be fever, emaciation, and complications such as perforation and limited abscess, when the lesion has entered the most advanced stage. 2.Left-sided colon cancer is prone to stenosis and progressive intestinal obstruction due to the narrow intestinal lumen of sigmoid colon and the acute angle with rectum, which may lead to persistent constipation and increase in the number of bowel movements. Since the obstruction is mostly in the lower sigmoid colon, vomiting is mild or absent, while abdominal distension, abdominal pain, bowel sounds and bowel pattern are obvious. When the cancer breaks down, it may cause blood or mucus to stain the outside of the stool. The obstructed proximal intestinal canal may form ulcers due to persistent distension, ischemia and hypoxia, and even cause perforation, and large amount of blood and abdominal abscess may also occur. 3.Proctal cancer mainly manifests as increased number of stools, thin stools with blood or mucus, accompanied by shortness of breath. As the cancer can invade the sacral plexus nerve, severe pain can occur. If the bladder is involved, symptoms such as frequent urination, painful urination, urgent urination and blood in urination may appear. If the cancer invades the bladder, it can form a vesico-rectal fistula. Rectal cancer can also cause intestinal obstruction. 4. Anal canal cancer mainly manifests as blood in stool and pain. The pain is aggravated when defecating. When the cancer invades the anal sphincter, fecal incontinence may occur. Anal canal cancer can metastasize to inguinal lymph nodes, so enlarged and hard lymph nodes can be palpated in the groin.