The vast majority of people who are diagnosed with colon cancer are over the age of 50. In fact, the average age of colon cancer diagnoses in the United States is 68 for men and 72 for women. However, colon cancer can and does occur in people in their teens, twenties, thirties, and forties. These ages of diagnosis are typical in people with hereditary cancer syndromes. Unfortunately, symptoms of colon cancer in young people are often ignored, dismissed, or misdiagnosed.

It is recommended that everyone at average risk start regular colon screening at age 45. This may be done using a stool-based test or with a visual exam, such as a colonoscopy. However, there are two things that may indicate you should have colon screening earlier than age 45:

  1. If you are experiencing any of the following warning signs for colorectal cancer, please speak to your health care provider about having a screening colonoscopy:
    • Rectal bleeding, blood in your bowel movements, or plum-colored stools
    • A change in your bowel habits (diarrhea or constipation) that lasts more than two weeks
    • Unexplained weight loss
    • Abdominal discomfort (pain, cramps, gas) that lasts more than two weeks
    • A feeling that your bowel does not empty completely
    • New weakness or fatigue that lasts more than two weeks
  2. You need to explore your family history to see if there are clues that may indicate you need a colonoscopy at a younger age. And it’s not just a family history of colon cancer you should be thinking of here.

Pro Tip: If you know something is wrong, advocate for yourself. Tell your health care provider that you know something is wrong and persist. If need be, get a second opinion.

If you have a personal and/or family history of any of the following, you may be at increased risk for a hereditary colon cancer syndrome:

  1. Early-onset colon, uterine, or gastric cancer before age 50
  2. Any of these clusters of cancers or physical findings on the same side of the family:
    • Colon, uterine, ovarian, biliary tract, or urinary tract cancers
    • Multiple adenomas (a type of colon polyps)
    • Desmoid tumors (rare, benign tumors that arise from connective tissue)
    • Osteomas (bony growths)
  3. The occurrence of multiple, primary (new) cancers in one individual
    • For example, colon, uterine, and ovarian cancers
  4. Individuals with multiple and/or early-onset gastrointestinal polyps with cumulative totals of:
    • More than 10 adenomatous polyps
    • More than 5 hamartomatous or juvenile polyps
    • Two or more confirmed Peutz-Jeghers hamartomatous polyps
  5. The following rare or unusual tumors or physical findings:
    • Sebaceous carcinomas/adenomas
    • Multiple trichilemmomas/oral papillomas
  6. Any Lynch syndrome-related tumor (most likely colorectal or uterine) tumor that has abnormal MSI or IHC testing
  7. There is a known genetic mutation (e.g. MLH1, MUTYH, APC) in your family

Please contact a certified genetic counselor if any of the above red flags are seen in your personal or family history so that you can learn your options for genetic testing and early surveillance.