Colorectal cancer and radiation therapy

I. Incidence

    According to the 91st National Cancer Registry Report of the National Health Service of the Executive Yuan, Department of Health, the incidence and mortality rate of colorectal cancer among Chinese people ranks third among the top ten cancers of both sexes. For rectal cancer, 4525 new men and 3370 new women. The incidence of colorectal cancer is 60-65 years old, so people over 50 years old are best screened. If colorectal cancer can be diagnosed and treated early, the cure rate is very high. For complete resection, the cure rate can be as high as 90% or more.

Common symptoms

The symptoms of most colorectal cancers are quite similar to those of other benign intestinal diseases, so it is sometimes difficult to distinguish them. The common clinical symptoms can be distinguished according to the tumor site:

  Ascending colon: It is located on the right side of the abdomen. Because of the large diameter of the structure, the tumor is less likely to cause obstruction. It is often caused by ulceration and bleeding on the surface of the tumor. Faint pain and weight loss were diagnosed at the hospital.

  Descending colon: located on the left side of the abdomen, where the diameter of the large intestine is narrower than that of the right large intestine. When tumors occur, intestinal obstruction can cause constipation, abdominal distension and even abdominal pain. If the obstruction is severe, the excrement becomes thinner. In addition, changes in bowel habits and hemolysis are common symptoms.

  Rectal cancer: The location is very close to the anus. The tumor will cause greater irritation to the anal mucosa, and there is a phenomenon of "emergency after heavy", that is, often want to defecate but not clean, sometimes severe constipation and Hemolysis will be the case.

Third, the treatment

The treatment of cancer needs to determine the cancer stage, and then select the treatment method according to the stage. The main treatment methods are as follows:

  Surgical treatment: When the symptoms of colorectal cancer are local, the most important treatment method is surgical resection. The principle of surgical resection is to remove the intestinal tract of the main lesion, remove adjacent lymph nodes, and then reconnect the intestine to maintain its original function. If necessary, an intestinal ostomy (artificial anus) is performed. Ask your colorectal surgeon for details.

  Chemotherapy: For cancer patients in the middle and late stages, postoperative adjuvant chemotherapy will be implemented to reduce the chance of recurrence and reduce mortality; in addition, there is a lot of new evidence showing that preoperative (leading) chemotherapy can reduce The scope of surgery can even make some of the large-scale symptoms that were originally diagnosed as inoperable and become operable. Ask your colorectal surgeon or hematologist for details.

  Radiation therapy: Before discussing this part, we need to separate colon cancer and rectal cancer. Because of the location of the colon, radiotherapy does not play an important role in colon cancer; however, in rectal cancer, radiotherapy has a great effect. The main reason is that the rectum is located in the pelvic cavity and is a relatively fixed organ. So it can be irradiated with radiation very accurately. For patients with rectal cancer whose tumor has penetrated the intestinal wall or had lymph node metastasis, radiotherapy should be added after surgery to reduce the chance of local recurrence. In addition, there is a lot of new evidence showing that preoperative radiation therapy can reduce tumor volume, can diagnose some large-scale symptoms that were previously inoperable, and become operable, even "anal sphincter preservation surgery", that is, After radiation therapy, only minor surgery is required. Ask your radiation oncologist for details.

4. Possible side effects and precautions of radiation therapy

  Common acute side effects occur during radiation therapy and will gradually relieve after treatment. Common symptoms include lower abdominal discomfort, frequent urination, diarrhea, bloody stools and other temporary symptoms. Among them, diarrhea is caused by increased bowel movements caused by radiation therapy, and the number of bowel movements can be increased. When returning home after radiation treatment, pay attention to:

1. It is forbidden to spit out milk, vegetables and fruit residues, so that the stomach can rest.

2. When the symptoms of diarrhea are relieved, adopt a gradual diet, such as: drinking water → light diet (such as porridge, white toast, etc.) → return to normal diet after no symptoms.

3. Properly add water such as sports drinks; and milk, meat, greasy, fried and spicy foods should be avoided.

4. Attention should be paid to changes in stool color, nature, and volume.

5. Keep the skin around the anus clean after using the toilet, and use a towel to soak up the water and avoid friction. Use only the medicine prescribed by your doctor when necessary.

6. Keeping the environment quiet and more bed rest can slow down gastrointestinal motility and reduce diarrhea.

7. If you have no diarrhea after returning home, you can stop taking the antidiarrheal medicine.

8. If the diarrhea does not stop, there is blood in the stool, fever, or dehydration symptoms such as dry lips and orbital depression, you should immediately return to the hospital for treatment.

  There are other advanced side effects that may occur, including chronic rectal bleeding, fibrosis or necrosis of tissues, formation of fistulas, intestinal stenosis and obstruction or destruction of peripheral nerves; however, these side effects are becoming more and more sophisticated in radiation treatment technology It is very rare today.