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Colon Cancer 101E ach year, there are 49,920 deaths from colorectal cancer. In America, 106,100 new cases of colon cancer and 40,870 new cases of rectal cancer will be discovered this year as well. Colon cancer patients have cancerous cells in the longest part of their upper large intestine, which is the 4 to 5 feet known as "the colon," whereas the affected area in rectal cancer patients is in the last six inches of the colon closest to the anus. There are five different stages of colon cancer; a cancer that affects the four to five feet of the upper large intestine. In Stage 0, the cancer hasn't grown past the mucosa of the colon. In Stage I, the cancer has grown through the mucosa but hasn't spread past the colon wall. In Stage II, the cancer has penetrated the wall of the colon, but hasn't yet spread further. In Stage III, the cancer has invaded the surrounding lymph nodes. In Stage IV, the cancer has spread to distant organs through the cancerous lymph nodes. Although 49,920 deaths occur from colorectal cancer each year, it's believed many of these deaths could have been prevented with early detection and treatment. In the past, colon cancer was a death sentence. Colon cancer patients had no idea they had this cancer until it was much too late. They would come to their doctors with Stage III or IV cancer, usually with bloody stools, abdominal pain, cramps, gas and overwhelming fatigue. Once the cancer had spread, there was little hope of controlling it. Today, much more is known about colon cancer risks, testing and treatment procedures. There are many important risk factors for cancer of the colon that makes someone a good candidate for colon cancer screening. Age is one factor, as about 90% of people diagnosed with this cancer are over 50. People are also more at-risk if they have ever had colorectal cancer, polyps, ulcerative colitis, Crohn's disease, diabetes, acromegaly (a growth hormone disorder) or radiation therapy as part of another cancer treatment. Some studies have shown that a greater risk exists for people who eat diets low in fiber and high in fat/calories, or diets high in red meat/processed meats. Obese individuals and smokers have an increased chance of developing and dying from this type of cancer too. As with most health conditions, genetics also play a role in many cases. Often times, the symptoms of colon cancer never show up until it's too late. Most colon cancer patients report a change in bowel habits, such as diarrhea or constipation. Some people notice rectal bleeding or bloody stools. It's common to feel persistent cramps, gas, abdominal pain, weakness and the feeling that the bowels aren't emptying completely. Some patients report sudden, unexplained weight loss and fatigue. Patients are advised to seek medical attention if there is a persistent change in bowel movements. People who are over 50 are urged to begin screening colonoscopy procedures regularly. The cause of colon cancer is the uncontrolled growth, division and replication of altered cells, which stack up in the intestinal lining. In later stages, the cancer can penetrate the colon walls, spreading to lymph nodes and other organs. Precancerous growths, called colon polyps, appear as mushroom-shaped bumps or recessed lesions in the colon walls. There are three main types of colon polyps: inflammatory, adenoma and hyperplastic. Inflammatory polyps often come after having ulcerative colitis and are usually removed because they often become cancerous if left unattended. Adenomas are also removed to avoid cancer development. By contrast, hyperplastic polyps are rarely a cause for concern. Approximately 5% of all colon cancer is caused by a genetic syndrome passed through the familial line. These syndromes include FAP (familial adenomatous polyposis) and Lynch syndrome (hereditary nonpolyposis colorectal cancer). About 95% of the people diagnosed with either syndrome will develop colon polyps that lead to cancer. The good news is that both of these syndromes are detectable through genetic testing. The idea that someone without these syndromes will develop the cancer because an aunt, grandmother, sibling or parent has is still debated. Some say the family may have all been exposed to the same environmental conditions or unhealthy lifestyle. There are many screening procedures for colon cancer. The most basic is a stool blood test (or a fecal occult blood test), which allows a patient to take a kit home, create a sample and return that sample to the lab, where a doctor will examine the results under a microscope. Similarly, a stool DNA test will send the sample kit off to the laboratory for more in-depth analysis, which may be able to indicate DNA mutations or tumors that indicate the presence of cancer. A flexible sigmoidoscopy takes just a few moments, and involves a flexible, slender, lighted tube being inserted into the last two feet of the rectum and colon to see if any colon polyps are present. A barium enema uses a contrast dye and x-rays to evaluate the lining of the bowels. A colonoscopy is similar to the sigmoidoscopy, but the instrument allows the doctor the ability to search the entire colon and rectum for polyps, rather than just the lower portion. Lastly, a virtual colonoscopy uses a computerized tomography machine to take images of the colon, which is a less invasive than a conventional colonoscopy screening. Surgery is the primary treatment of advanced colon cancer, where the affected portion of the colon is removed. Sometimes the healthy portions of the colon can simply be reconnected, while other times a bag must be inserted to collect waste. In the early stages, cancerous polyps can be removed with the colonoscope during screening or through non-invasive laparoscopic surgery. Metastatic colon cancer usually requires chemotherapy and/or radiation therapy to remove any leftover cancer that has migrated through the body. Additionally, an exciting new field called "targeted drug therapy" uses the drugs bevacizumab (Avastin), cetuximab (Erbitux) and panitumumab (Vectibix) to prevent tumors from developing new blood vessels (thereby cutting off the nutrient/oxygen flow to cancerous cells) and to inhibit the chemical signal that causes these harmful cells to reproduce. The American Cancer Society has issued some guidelines to prevent colon cancer. Once a person reaches 50, they should receive an annual fecal occult blood test, stool DNA testing, a flexible sigmoidoscopy and a double-contrast barium enema every five years, a colonoscopy every ten years and a virtual colonoscopy screening every five years. Additionally, certain lifestyle precautions are wise. Eat lots of fruits, vegetables and whole grains; limit fat, specially saturated fat and red meat fat; take vitamins and minerals, especially B-6, calcium, folic acid and magnesium; limit alcohol consumption to no more than a drink a day for women or two drinks a day for men; quit smoking; get at least 30 minutes of exercise on most days; and take an aspirin a day. |
