Wei Boli (Director of General Surgery, Affiliated Hospital of Taipei Medical College): Are colorectal cancer, colon cancer and rectal cancer the same? In medicine, what the general public calls colorectal cancer generally refers to "colon cancer". Many people think that the large intestine, colon and rectum are all intestines. As long as there is a tumor, the treatment should be the same. In fact, the structure and physiological function of large intestine and rectum are different, so the treatment methods are not exactly the same. The human digestive system starts from the mouth, and the order from top to bottom is esophagus → stomach → small intestine → large intestine → rectum → * *. In medicine, the large intestine, rectum and * * *, the so-called lower digestive tract, belong to the last connected pipeline of the digestive tract and are places where feces pass or are stored. The large intestine refers to the ""-shaped colon ",which is usually called the large intestine. Medically, it refers to the colon, and the so-called colorectal cancer is colon cancer. The colon is located in the abdominal cavity, connecting the cecum from below the right lower abdominal ileum cecum valve, and extending upward is called ascending colon; Then pass through the whole abdomen to the left, called transverse colon; Then descending to the left lower abdomen is called descending colon; Then connect the sigmoid colon, and finally connect the rectal segment and the mouth. This large intestine is the "colon" (from cecum to sigmoid colon), with a total length of about 120 to 140 cm. It occupies the periphery of abdomen in zigzag shape (see figure 1), and its main function is to absorb food residue, water, electrolyte, etc. It is left behind after being used by the human body, and then slowly forms feces. Colorectal cancer is colon cancer. When a malignant tumor grows in any part of the colon, it is called colon cancer. If we subdivide the growth position, we will use this position as the name of the tumor. For example, if the tumor grows in the ascending colon, it is called "ascending colon cancer"; When it grows in the sigmoid colon, it is called sigmoid colon cancer. Knowledge Post-It notes that the colon and rectum belong to the lower digestive system. The colon (large intestine) is in the shape of ""in the abdominal cavity, which absorbs the residual water and electrolyte that are not absorbed in the body and slowly forms feces. The rectum is the end of the digestive tract, connecting the sphincter, and its main function is to store feces. Remarks: For the sake of unification, all colon cancer words in this book are collectively referred to as colorectal cancer. Rectal cancer is a kind of cancer that grows in the rectum. The rectum is the small intestine connected between the sigmoid colon and * * *, and it is about 12 to 15 cm long (as shown in figure 1). Its main function is to store feces. If the tumor grows in the rectum, it is called "rectal cancer". Although medically, rectum and * * * also belong to the lower digestive tract. However, because the physiological structure of rectum is different from that of large intestine, when tumors grow in this part, the probability of local recurrence is higher than that of colon cancer even after complete treatment. Therefore, in addition to retaining the function of * * *, it is also necessary to reduce the probability of local recurrence. Therefore, every time a doctor emphasizes colorectal cancer or rectal cancer to a patient, it is not that the doctor is picky or empty talk, but that the treatment methods of these two cancers are very different. Wei Boli (Director of General Surgery, Affiliated Hospital of Taipei Medical College): Are colorectal cancer, colon cancer and rectal cancer the same? In medicine, what the general public calls colorectal cancer generally refers to "colon cancer". Many people think that the large intestine, colon and rectum are all intestines. As long as there is a tumor, the treatment should be the same. In fact, the structure and physiological function of large intestine and rectum are different, so the treatment methods are not exactly the same. The human digestive system starts from the mouth, and the order from top to bottom is esophagus → stomach → small intestine → large intestine → rectum → * *. In medicine, the large intestine, rectum and * * *, the so-called lower digestive tract, belong to the last connected pipeline of the digestive tract and are places where feces pass or are stored. The large intestine refers to the ""-shaped colon ",which is usually called the large intestine. Medically, it refers to the colon, and the so-called colorectal cancer is colon cancer. The colon is located in the abdominal cavity, connecting the cecum from below the right lower abdominal ileum cecum valve, and extending upward is called ascending colon; Then pass through the whole abdomen to the left, called transverse colon; Then descending to the left lower abdomen is called descending colon; Then connect the sigmoid colon, and finally connect the rectal segment and the mouth. This large intestine is the "colon" (from cecum to sigmoid colon), with a total length of about 120 to 140 cm. It occupies the periphery of abdomen in zigzag shape (see figure 1), and its main function is to absorb food residue, water, electrolyte, etc. It is left behind after being used by the human body, and then slowly forms feces. Colorectal cancer is colon cancer. When a malignant tumor grows in any part of the colon, it is called colon cancer. If we subdivide the growth position, we will use this position as the name of the tumor. For example, if the tumor grows in the ascending colon, it is called "ascending colon cancer"; When it grows in the sigmoid colon, it is called sigmoid colon cancer. Knowledge Post-It notes that the colon and rectum belong to the lower digestive system. The colon (large intestine) is in the shape of ""in the abdominal cavity, which absorbs the residual water and electrolyte that are not absorbed in the body and slowly forms feces. The rectum is the end of the digestive tract, connecting the sphincter, and its main function is to store feces. Remarks: For the sake of unification, all colon cancer words in this book are collectively referred to as colorectal cancer. Rectal cancer is a kind of cancer that grows in the rectum. The rectum is the small intestine connected between the sigmoid colon and * * *, and it is about 12 to 15 cm long (as shown in figure 1). Its main function is to store feces. If the tumor grows in the rectum, it is called "rectal cancer". Although medically, rectum and * * * also belong to the lower digestive tract. However, because the physiological structure of rectum is different from that of large intestine, when tumors grow in this part, the probability of local recurrence is higher than that of colon cancer even after complete treatment. Therefore, in addition to retaining the function of * * *, it is also necessary to reduce the probability of local recurrence. Therefore, every time a doctor emphasizes colorectal cancer or rectal cancer to a patient, it is not that the doctor is picky or empty talk, but that the treatment methods of these two cancers are very different. What is the difference between the treatment of rectal cancer and colorectal cancer? The rectum is the end of the intestine, only 12 to 15 cm long, close to * * *, and its main function is to store feces. However, because its physiological structure is different from that of large intestine, the probability of local recurrence of tumor is high, and the function of * * should be preserved during treatment to reduce the probability of local recurrence, so the treatment of rectal cancer is much more complicated. Case sharing: Teacher Lin's treatment of rectal cancer is more complicated than that of colorectal cancer. Miss Lin, who was diagnosed with stage III colorectal cancer, also received a full course of chemotherapy after operation. After that, she visited the doctor regularly, and all the tests were safe during the process. However, after five years of follow-up, I felt that my defecation habits changed and I bled for about a month. She suspected that her colorectal cancer had recurred, so she went back to the hospital for examination. After arranging colonoscopy, it was found that there was a tumor in the rectum very close to * * *, which was not the surgical site of colorectal cancer before, but belonged to another new tumor-rectal cancer. When the medical team communicated with her about her illness and explained the treatment of rectal cancer, there was a discussion about the possibility of artificial surgery. The more she listened, the more complicated she felt. She looked puzzled and said, "Last time I got colorectal cancer, I cut it off directly after the examination, and then I had to do several chemotherapy. Why is the treatment of rectal cancer so complicated this time? But also may have to do artificial * * *? The physiological structures of rectum and large intestine are different. Compared with the large intestine, the intestinal wall of rectum lacks a structure called serosa layer and a protective layer, so there is less barrier when rectal tumor metastasizes, which is also the reason for the high local recurrence rate of rectal cancer. In addition, almost all the intestines of the large intestine are located in the abdominal cavity, and the rectum is located in the deepest and narrowest part of the pelvic cavity. Therefore, the difficulty of rectal cancer surgery is much higher than that of colorectal cancer. The new treatment mode greatly improves the probability of * * * retention. In the past years, if the rectal tumor grows within seven centimeters from the mouth of the rectum, it may be necessary to undergo excision and permanent artificial operation, which not only causes great physical and mental shock and panic to the people, but also reduces the quality of life of the patients. However, after receiving such destructive treatment, the control rate of recurrence and metastasis of rectal cancer can not be improved, nor can it be improved for patients. In recent years, more and more tumor therapists at home and abroad have been studying and treating rectal cancer more and more deeply. In addition to improving the cure rate of cancer and reducing the probability of local recurrence and metastasis, it is also hoped that the rectum and rectum can be preserved as much as possible when rectal tumors are removed by surgery. It is hoped that after the disease is controlled, patients can still maintain a good quality of life and minimize rectal and rectal damage. At present, for this kind of tumor close to the mouth of * * * *, besides CT examination to see whether there is liver metastasis, it is suggested to do pelvic nuclear radiation examination to determine the depth of rectal tumor invading intestinal wall, the boundary between tumor and surrounding tissues, the size and number of local lymph nodes, etc. When these imaging tests are completed, the cancer stage can be preliminarily determined. If the clinical stage of rectal cancer is stage two or three, according to the clinical practice guidelines of oncology NC, preoperative radiotherapy combined with chemotherapy (or radiotherapy combined with chemotherapy first) should be accepted. After the course of treatment, the effect of radiotherapy will last for a period of time, and then slowly fade away. Usually, the operation time is six to twelve weeks after the end of radiotherapy, and radiotherapy combined with chemotherapy will be reviewed and evaluated before operation. Examination items include: colonoscopy, chest X-ray or computed tomography, abdominal computed tomography and pelvic nuclear radiography. After tumor resection, the cut tissue will be sent to the pathology department for complete microscopic analysis, and then there will be a final pathological report. No matter which stage is determined by pathological report, postoperative adjuvant chemotherapy must be carried out again. Before operation, radiotherapy combined with chemotherapy was arranged for a period of time in order to narrow the tumor range. After the tumor shrinks, surgical resection can increase the safe distance between tumor clearance and resection, which not only improves the probability of successfully retaining * * * in patients with rectal cancer, but also greatly reduces the risk of local tumor recurrence or metastasis. This article is excerpted from 50 Key Questions about Colorectal Cancer/Wei Boli (Director of General Surgery, Affiliated Hospital of Taipei Medical College, Associate Professor of Internal Surgery, Taipei Medical College)/Symptoms of Colorectal Cancer The American Society of Colorectal Surgeons pointed out that colorectal cancer is often asymptomatic, but in routine examination, it should also be noted that the symptoms of colorectal cancer are often similar to other diseases. For example, hemorrhoids are one of the common causes of hematochezia, but they do not cause colorectal cancer. Changes in defecation habits (such as constipation and diarrhea), thin stool, bright red or dark red blood in stool, persistent pelvic pain, flatulence or abdominal distension, weight loss, nausea and vomiting, fatigue, lower abdominal pain and weight loss caused by unknown reasons are typical terminal symptoms, suggesting that there may be a wide range of hidden diseases in the body. Therefore, if the above symptoms appear, it is recommended to seek medical treatment to prevent serious diseases. Surgical treatment of colorectal cancer The American Society of Colorectal Surgery believes that if we want to completely treat colorectal cancer, almost all cancerous sites need to be removed, including tumors, lymph nodes and a small part of normal intestines around the tumors. According to the stage of colorectal cancer, chemotherapy may be needed before and after operation. Compared with rectal cancer, colorectal cancer needs less radiotherapy. Colorectal cancer screening According to the data of the National Cancer Institute, studies show that some colorectal cancer screening may help to find early cancer and reduce the mortality caused by cancer. The commonly used methods for screening colorectal cancer are: fecal occult blood test, sigmoidoscopy, colonoscopy, and virtual colonoscopy: the image processing after computer scanning shows similar inspection effect to colonoscopy. Fecal DNA test (DNA fecal test)