Signs and Symptoms of Colon Cancer
Article date: March 3, 2014
Ideally, people are tested for colon cancer before they ever experience symptoms. Symptoms usually only appear after the cancer has grown or spread. Colon cancer that’s found through screening – testing that’s done on people with no symptoms – is usually easier to treat. Screening can even prevent some colon cancers by finding and removing pre-cancerous growths called polyps.
However, if colon symptoms do occur, they can let you know you have a problem and should go to the doctor. Most of the time, these same symptoms are caused by something that isn’t cancer, such as infection, hemorrhoids, irritable bowel syndrome, or inflammatory bowel disease. Still, if you have any of these problems, it's important to see your doctor right away so the cause can be found and treated, if needed:
- A change in bowel habits, such as diarrhea, constipation, or narrowing of the stool, that lasts for more than a few days
- A feeling that you need to have a bowel movement that is not relieved by doing so
- Rectal bleeding, dark stools, or blood in the stool (often, though, the stool will look normal)
- Cramping or abdominal (belly) pain
- Weakness and fatigue
- Unintended weight loss
Screening could save your life
Because colon cancer doesn’t usually cause symptoms until it is advanced, the American Cancer Society recommends regular colon cancer screening for most people starting at age 50. People with a family history of the disease or other risk factors should talk with their doctor about beginning screening at a younger age.
Several different tests can be used to screen for colon cancer. According to Centers for Disease Control and Prevention (CDC) Director Tom Frieden, MD, MPH, it’s important to learn about the different types of screening, know your family history, and encourage your friends and family to get tested. Frieden said, “If you haven’t been screened, see your provider about getting screened. It could save your life.”
When colon cancer is found early, before it has spread, the 5-year survival rate is 90%. This means 9 out of 10 people with early-stage cancer survive at least 5 years.
How do they know if it’s cancer?
If your doctor finds something suspicious during a screening exam, or if you have any of the symptoms associated with colon cancer, your doctor will probably recommend exams and tests to find the cause.
Your doctor may want to take a complete medical history to check for symptoms and risk factors, including your family history. As many as 1 in 5 people who develop colon cancer have other family members – especially parents, brothers and sisters, or children – who’ve had it. Having other colon problems can also increase risk. This includes pre-cancerous polyps, ulcerative colitis, Crohn’s disease, and hereditary syndromes such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colon cancer (HNPCC), also known as Lynch syndrome. Having type 2 diabetes can also increase risk.
As part of a physical exam, your doctor will carefully feel your abdomen and also examine the rest of your body. You might also get certain blood tests to help determine if you have colon cancer.
If symptoms or the results of exams or tests suggest that you might have colon cancer, your doctor may recommend more tests, such as colonoscopy, sigmoidoscopy, or an x-ray or CT scan of your colon. If a suspected colon cancer is found by any of the tests, it is usually biopsied during a colonoscopy. In a biopsy, the doctor removes a small piece of tissue with a special instrument passed through the scope.
If you are diagnosed with colon cancer, treatment depends on how early it is found, but may include surgery, radiation, chemotherapy, and targeted therapies. It’s important for you to be able to talk frankly and openly with your doctor, and if you don’t understand something, to ask questions. Here is a list of questions to ask your doctor that you can take with you.
Reviewed by: Members of the ACS Medical Content Staff
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