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1、 Colorectal CancerWhat is it ? It is the third most frequently diagnosed cancer in men and women and the second highest cause of cancer deaths in the U.S. Yet, when found early, it is highly curable. This type of cancer occurs when abnormal cells grow in the lining of the large intestine (colon) or
2、rectum. Learn more about who gets colorectal cancer, how it is detected, and what the latest treatments can accomplish.How it starts ? It often begin as polyps benign growths on the surface of the colon. The two most common types of intestinal polyps are adenomas and hyperplasic polyps. They develop
3、 when there are errors in the way cells grow and repair the lining of the colon. Most polyps remain benign, but some have the potential to turn cancerous. Removing them early prevents colorectal cancer.Risk Factors You Cant Controlgenetics & lifestyle. Age most patients are older than 50 Polyps or i
4、nflammatory bowel disease Family history of colorectal cancer History of ovarian or breast cancerRisk Factors You Can Control Diet high in red, processed, or heavily cooked meats Being overweight (excess fat around the waist) Exercising too little Smoking or drinking alcoholIts warning Signs There a
5、re usually no early warning signs for colorectal cancer. For this reason its important to get screened. Detecting cancer early means its more curable. As the disease progresses, patients may notice blood in the stool, abdominal pain, a change in bowel habits (such as constipation or diarrhea), unexp
6、lained weight loss, or fatigue. By the time these symptoms appear, tumors tend to be larger and more difficult to treat.Screening Because colorectal cancer is stealthy, screenings are the key to early detection. Beginning at age 50, most people should have a colonoscopy every 10 years. This procedur
7、e uses a tiny camera to examine the entire colon and rectum. These tests not only find tumors early, but can actually prevent colorectal cancer by removing polyps (shown here).Virtual Colonoscopy There is now an alternative to colonoscopy that uses CT scan images to construct a 3 -D model of your co
8、lon. Called virtual colonoscopy, the procedure can reveal polyps or other abnormalities without actually inserting a camera inside your body. The main disadvantage is that if polyps are found, a real colonoscopy will still be needed to remove and evaluate them.X-Rays of the Colon (Lower GI) X-Rays o
9、f the colon - using a chalky liquid known as barium as a contrast agent - allow your doctor a glimpse at the interior of the colon and rectum, offering another way to detect polyps, tumors, and changes in the intestinal tissue. Shown here is an “apple core“ tumor constricting the colon. Like the vir
10、tual colonoscopy, any abnormalities that appear on the X-rays will need to be followed up with a conventional colonoscopy.Diagnosing Colorectal Cancer If testing reveals a possible tumor, the next step is a biopsy. During a colonoscopy, your doctor will remove polyps and take tissue samples from any
11、 parts of the colon that look unusual. This tissue is examined under a microscope to determine whether or not it is cancerous. Shown here is a color-enhanced, magnified view of colon cancer cells.Staging Colorectal Cancer If cancer is detected, it will be “staged,“ a process of finding out how far t
12、he cancer has spread. Tumor size may not correlate with the stage of cancer. Staging also enables your doctor to determine what type of treatment you will receive. I Cancer has not spread beyond the inside of the colon or rectum II Cancer has spread into the muscle layer of the colon or rectum III -
13、 Cancer has spread to one or more lymph nodes in the area IV Cancer has spread to other parts of the body, such as the liver, lung, or bones. This stage does NOT depend on how deep the tumor has penetrated or if the disease has spread to the lymph nodes near the tumor.Colorectal Cancer Survival Rate
14、s The outlook for your recovery depends on the stage of your cancer, with higher stages meaning more serious cancer. The five-year survival rate refers to the percentage of patients who live at least five years after being diagnosed. Stage I has a 93% five-year survival rate while stage IV has a fiv
15、e-year survival rate of only 8%.Colorectal Cancer Surgery In all but the last stage of colorectal cancer, the usual treatment is surgery to remove the tumor and surrounding tissue. In the case of larger tumors, it may be necessary to take out an entire section of the colon and/or rectum. The good ne
16、ws is that surgery has a very high cure rate in the early stages. If the cancer has spread to the liver, lungs, or other organs, surgery is not likely to offer a cure - but removing the additional tumors, when possible, may reduce symptoms.Treating Advanced Colorectal Cancer When colorectal cancer has spread to one or more lymph nodes (stage III),
