How to know if colon cancer ?

MD: Colon cancer would be uncommon at your age but i suggest you talk to your family doctor to see if there is any reason (family history or personal history) to justify starting screening early or doing some diagnostic tests. Good for you to be aware but don't let this become an obsession. Best to you.

Get tested: There are many tests that have been developed to test either a patient with concerning symptoms or just as a routine screening exam in an a symptomatic patient. Each individual situation is different. Testing stool for blood or now genetic abnormalities, rectal exam, X-rays such as barium enema or ct scan virtual colonoscopy are examples. Best is colonoscopy as you can both look and do.

Only way: To know for sure is by colonoscopy. If you are not in a high risk group and have no symptoms such as abdominal cramping, blood in stool, or anemia, your chances of colon cancer before age 50 is pretty low. Talk to your doctor about getting proper tests.

Colonoscopy: Colonoscopy + biopsy as indicated. If you do have risk factors, you should have your first screening colonoscopy at age 50.