Malignant Neoplasm of Sigmoid Colon: Colon Cancer – Symptoms and Causes
What is colon cancer?. How common is colon cancer?. What are the risk factors for colon cancer?.
What is Colon Cancer?
Colon cancer forms in the tissues of the colon, which is part of the large intestine. The colon is part of the body’s digestive system, which is made up of the esophagus, stomach, and the small and large intestines. The first six feet of the large intestine are called the colon, and the remaining several inches form the rectum.
Different types of cancer can develop in the colon, but most colon cancers are adenocarcinomas, which are cancers from glandular tissue. Other cancer types that can occur in the colon include carcinoid tumors, small cell carcinomas, and gastrointestinal stromal tumors (GIST). The focus of this information is on colon cancers that are adenocarcinomas.
How Common is Colon Cancer?
Colon and rectal cancers are the fourth most common cancers diagnosed in the United States. Survival after diagnosis has been gradually increasing in the past decade. This is due to several reasons, including screening programs that can catch the disease in its pre-cancerous or early stages, which are more curable, and better treatments, both surgical techniques and chemotherapies, including targeted therapies.
Most colon cancers start as polyps, or growths in the colon. Over time, some, but not all polyps change into cancers. Polyps that have a higher risk of becoming cancer are known as adenomas. The reason screening is so important is that finding polyps before they become cancer reduces the risk of developing colon cancer by at least 90 percent.
What are the Risk Factors for Colon Cancer?
Risk factors for colon cancer include increasing age, with most people who develop colon cancer being 50 or older, a family history of cancer of the colon or rectum, certain hereditary conditions such as familial adenomatous polyposis and hereditary nonpolyposis colon cancer (Lynch syndrome), a history of inflammatory bowel disease (IBD) such as ulcerative colitis and Crohn’s disease, and a personal history of cancer of the colon, rectum, ovary, endometrium, or breast.
A personal or family history of adenomas (polyps) in the colon or rectum can also increase the risk of developing colon cancer, as these growths can be pre-cancerous. Regular screening to remove them reduces the risk of developing colon cancer.
What are the Symptoms of Colon Cancer?
What are the symptoms of colon cancer? Colon cancer can cause a variety of symptoms, including changes in bowel habits, such as diarrhea, constipation, or narrowing of the stool, rectal bleeding or blood in the stool, abdominal discomfort, such as cramps, gas, or pain, a feeling of not being able to fully empty the bowel, and unexplained weight loss.
These symptoms can be caused by conditions other than colon cancer, so it’s important to see a healthcare provider if you experience any of them. Early detection is key, as colon cancer is highly treatable when caught early.
How is Colon Cancer Diagnosed?
How is colon cancer diagnosed? Colon cancer is typically diagnosed through a combination of tests, including a physical exam, blood tests, imaging tests such as a colonoscopy or CT scan, and biopsy. A colonoscopy is the gold standard for detecting and diagnosing colon cancer, as it allows the healthcare provider to visually inspect the entire colon and rectum and take samples of any suspicious areas for further testing.
If colon cancer is detected, additional tests may be performed to determine the stage of the cancer and develop a treatment plan. Early detection is crucial, as colon cancer is highly treatable when caught in its early stages.
How is Colon Cancer Treated?
How is colon cancer treated? The treatment for colon cancer depends on the stage of the cancer, the location of the tumor, and the overall health of the patient. Common treatment options include surgery to remove the tumor, chemotherapy, radiation therapy, and targeted therapies.
Surgery is often the first line of treatment for colon cancer, and may involve removing the tumor and a portion of the healthy tissue surrounding it. Chemotherapy may be used before or after surgery to help shrink the tumor or kill any remaining cancer cells. Radiation therapy may also be used, particularly for rectal cancers. Targeted therapies, which target specific genetic or molecular changes in cancer cells, are also being increasingly used to treat colon cancer.
What is the Prognosis for Colon Cancer?
What is the prognosis for colon cancer? The prognosis for colon cancer depends on the stage of the cancer at the time of diagnosis. When caught early, colon cancer is highly treatable, with a 5-year survival rate of over 90% for stage I cancers. However, as the cancer becomes more advanced, the prognosis declines, with the 5-year survival rate dropping to around 14% for stage IV cancers.
That said, even for more advanced cases, new treatments are constantly being developed and the overall prognosis for colon cancer has been improving in recent years. With early detection and comprehensive treatment, many patients with colon cancer can go on to live long, healthy lives.