Colorectal cancer is a common cancer that mainly affects people over 60 years old. Colorectal cancer affects the colon or rectum in very similar ways. One of the only differences is the fact that it affects both men and the women equally in the case of colon cancer, whereas rectal cancer is twice as common in men as in women. It is approximately 70% in colon and 30% in the rectum. Dietary factors are involved: alcohol, animal fats and tobacco increase the risk, while dietary fiber and vegetables are protective. But there are also genetic forms, including some familial diseases such as familial adenomatous polyposis characterized by the existence of numerous polyps on the inner wall of the colon or rectum, which almost always evolves towards carcinogenesis before age the age of 40. Polyps are also potentially precancerous lesions, hence their frequent removal as a preventive measure.
Colorectal cancer can be manifested with different symptoms:
- bowel dysfunction, with diarrhea, constipation, or alternating between these two disorders;
- bleeding red blood from the anus;
- abdominal pain;
- desires to defecate without any result, frequently in rectal cancer;
If suggestive symptoms are present, the doctor may need to perform a digital rectal exam, because rectal tumors are sometimes palpable with the finger. But the most useful test in this context is a colonoscopy, which uses a mini camera to view the inside of the rectum and colon. Often performed under general anesthesia, it allows the study of the mucosa and the location of polyps and other lesions. It also makes it possible to study samples of the lesion, but also to remove polyps, potentially progressively cancerous lesions. After analysis, if a cancer is confirmed, various tests are carried out to investigate the extent of the nodes or to see if any other organs have been affected by cancer cells.
The treatment of colorectal cancer depends on the location of the tumor and its stage. Surgery is often preferred with ablation of the diseased. A colectomy is when the colon is removed completely. Chemotherapy can also be added on, while radiation therapy is rarely used.
It is possible to prevent colorectal cancer in particular by adopting a healthy life with a proper healthy diet (no red meat, sausage or grilled foods, but rather fish, whole grains, fruits and vegetables), regular exercise, and no smoking or alcohol. Screening for blood in stool from 50 years onwards allows an early diagnosis of these cancers. In addition, colonoscopy in the case doubt or if a family member has been diagnosed with colorectal cancer also allows an early discovery of cancer. In some familial forms such as familial adenomatous polyposis, early removal of polyps is mandatory.