Colon cancer is the third most common cancer in the United States, with over 150,000 cases diagnosed in 2024 and over 50,000 deaths. Howver, it is one of the most preventable cancers because of screening colonoscopy, but your risk increases significantly if colon cancer runs in your family. Knowing your family history—especially first-degree relatives like parents, siblings, or children—can make a life-saving difference when it comes to screening and early detection.
Roughly 1 in 3 people diagnosed with colorectal cancer have a close relative who also had it. If a first-degree relative was diagnosed, your risk doubles. If multiple relatives were affected or they were diagnosed before age 50, your risk climbs even higher. That’s because you may share not only genetics but also lifestyle and environmental factors that contribute to cancer risk. Again, note here, that it is only first-degree relatives with colon cancer that put you at higher risk– parents and siblings. Generally, grandparents, aunts, and uncles, especially if they were diagnosed later in life, do not contribute to this risk. MOST people (70-80%) do NOT have an inherited colon cancer syndrome, and cancer develops spontaneously, or out of the blue.
However, these inherited syndromes dramatically increase the risk of colon cancer:
Lynch syndrome (HNPCC): Increases lifetime colorectal cancer risk to 50–80%.
Familial adenomatous polyposis (FAP): Nearly 100% risk if untreated, often diagnosed in teens or early adulthood. (These syndromes need their own post, so more later.)
If you have a family history of colon cancer:
Start screening at age 40, or 10 years earlier than the age your first-degree relative was diagnosed—whichever comes first.
Colonoscopy is the preferred method because it not only detects cancer but also removes precancerous polyps.
You may need more frequent screenings (every 5 years instead of every 10).
If genetic syndromes are suspected, your doctor may recommend genetic testing and counseling.
Know your family history: Talk to your relatives and write it down—include ages at diagnosis.
Share it with your doctor: This information changes your screening plan.
Encourage family screening: Your siblings and children may be at risk too.
Adopt healthy habits: A diet high in fiber and low in red/processed meat, regular physical activity, and avoiding smoking or heavy alcohol use can lower your risk.
A family history of colon cancer doesn’t mean you’ll definitely get it—but it does mean you need to take action earlier and more often. Colon cancer is highly treatable when caught early, and even better, it’s often preventable.
Talk to your doctor, get screened, and stay ahead of your family history. Your future self will thank you.
Until next time, that’s just the way the anus wrinkles.
