What Is Early-Onset Colorectal Cancer?

As more people in their prime get this illness, scientists are searching for the reasons why and investigating the best ways to recognize, treat, and prevent this potentially life-threatening, but treatable, disease.
Signs and Symptoms of Early-Onset Colorectal Cancer
Because young people don’t expect to get colorectal cancer, they may ignore symptoms early on when the cancer is most treatable, says John Marshall, MD, the director of the Ruesch Center for the Cure of Gastrointestinal Cancers at Georgetown University in Washington, DC.
“We all need to be more aware of the symptoms so we take them seriously right away,” says Dr. Marshall, who also serves as chief medical consultant for the Colorectal Cancer Alliance.
- Blood in your stool
- Abdominal pain
- Bowel movement changes
- Fatigue and weakness (often caused by an iron deficiency)
- Unexplained weight loss
- Loss of appetite
Causes and Risk Factors of Early-Onset Colorectal Cancer
- Genetic Conditions Inherited physical problems such as Lynch syndrome and familial adenomatous polyposis (which can produce hundreds of polyps in the colon) increase the chances of developing colorectal cancer, especially at a young age.
The Global Colon Cancer Association estimates that 16 to 25 percent of early-onset cases are related to a genetic syndrome, whereas only up to 10 percent of regular colorectal cases are related to genetics. - Racial and Ethnic Background American Indian and Alaska Native people have the highest rates of colorectal cancer in the United States, followed by Black men and women. Jews of Eastern European descent (Ashkenazi Jews) also have a high risk compared to other ethnic groups; about 6 percent carry a specific gene mutation that increases their risk of developing colorectal cancer by two times.
- Other Health-Related Issues Certain health-related conditions may contribute to colorectal cancer risk, including a family history of the disease, a personal history of radiation to the abdomen or pelvis area, a personal history of inflammatory bowel disease (Crohn’s or ulcerative colitis), and having had the gallbladder removed (cholecystectomy).
- Toxins in the Environment Researchers are studying whether exposure to chemicals may play a role in colorectal cancer. Chemical exposures (from air and water pollution, chemicals in soil and food, and pesticide use) may damage the DNA of intestinal cells leading to cancer-causing mutations.
Modifiable Risk Factors
How Is Early-Onset Colorectal Cancer Diagnosed?
Colorectal Cancer Screenings
- Fecal Immunochemical Test (FIT) This screening detects blood in feces that may not be visible. This test is done once a year.
- Guaiac-Based Fecal Occult Blood Test (gFOBT) Like the FIT, this test looks for blood in feces that may be hidden and should be done annually.
- Fecal DNA Test This test looks for signs of genetic mutations and blood in feces. It should be performed every three years.
- Shield Blood Test Approved by the FDA in the summer of 2024 for use in people 45 and older, this test looks for the presence of specific changes to DNA floating freely in the blood, which indicate the presence of a tumor or precancerous growths in the colon.
- Flexible Sigmoidoscopy This uses a flexible scope to see inside the lower colon and rectum.
- Virtual Colonoscopy An X-Ray exam
Colonoscopy
Other Diagnostic Tests
- Complete blood count
- Comprehensive metabolic panel, a routine test to assess 14 substances in the blood, including electrolytes, blood sugar, cholesterol, and liver enzymes
- Carcinoembryonic antigen (CEA) assay, a test that measures CEA, a protein found in the blood that may be elevated in people with cancer
- Computed tomography (CT) scan
- Magnetic resonance imaging (MRI) scan
- Positron emission tomography (PET) scan
- Ultrasound
- Biopsy
Treatment for Early-Onset Colorectal Cancer
Diagnostic tests help clinicians determine what stage of cancer a patient may have. Younger people tend to be diagnosed when the cancer is at an advanced stage.
- Endoscopic Treatment Some polyps may be removed during a colonoscopy.
- Surgery Removal of cancerous tissue and possibly reconstructing the bowel
- Chemotherapy Drugs that travel through the bloodstream and destroy cancer cells
- Immunotherapy Drugs that help the body’s immune system recognize and kill cancer cells
- Targeted Therapies Treatment that targets the genetic changes or mutations that turn healthy cells into cancer cells
- Radiation Therapy High-energy rays (such as X-rays) that shrink or eliminate tumors
Disparities and Inequities in Early-Onset Colorectal Cancer
American Indian and Alaska Native people have the highest rates of colorectal cancer in the United States, followed by Black men and women.
Lifestyle Changes and Prevention of Early-Onset Colorectal Cancer
Screening tests like colonoscopy may identify precancerous polyps, which a doctor can remove to reduce cancer risk.
In addition to screening, young adults can reduce their colorectal cancer risk by adopting healthy lifestyle habits.
Claire Saxton, the executive vice president of insights and impact with the Cancer Support Community, recommends the following lifestyle changes:
- Increase physical activity.
- Maintain a healthy weight.
- Eat a diet low in animal fats and high in fruits, vegetables, and whole grains.
- Limit alcohol (two drinks or fewer a day for men, one drink or fewer a day for women).
- Avoid tobacco, or get help to quit.
- Limit sugar-sweetened drinks.
- Limit fast food, processed foods, and foods high in fat, starches, or sugars.
Prognosis of Early-Onset Colorectal Cancer
Complications of Early-Onset Colorectal Cancer
- Blockage of the colon: This prevents food, liquid, gas, and stool from passing through the intestines.
- Cancer returning in the colon: When cancer comes back, it can be more aggressive.
- Metastasis: When the cancer spreads to other organs or tissues.
- Development of a second primary colorectal cancer: This is development in a new location in the colon, distinct from any recurrence of the original tumor.
- Chronic diarrhea: Some cancer survivors have long-lasting bowel issues.
Support for Early-Onset Colorectal Cancer
People with early-onset colorectal cancer have their own online communities, patient support hub, and buddy program.
Find online meetups where those affected by early-onset colorectal cancer can engage in meaningful conversations.
Connect with adolescent and young adult cancer survivors and gain access to critical information and resources.
The SAM Fund — Expect Miracles Foundation
Grant money from this foundation can help young adult cancer survivors stay afloat.
The Takeaway
- The number of early-onset colorectal cancer cases is growing at a concerning rate. Scientists aren’t sure why this is occurring, but they’ve identified modifiable factors that heighten risk.
- Being aware of symptoms can help young adults know when to get screened. If you’re experiencing rectal bleeding, abdominal pain, or changes in bowel movements, speak with your doctor.
- While early-onset colorectal cancer is more likely to be at an advanced stage at diagnosis than in someone over the age of 50, it is still treatable, and often curable.
FAQ
Resources We Trust
- Cleveland Clinic: Center for Young-Onset Colorectal Cancer
- American Cancer Society: Colorectal Cancer Risk Factors
- Global Colon Cancer Association: Early-Onset Colorectal Cancer
- Yale Medicine: Colorectal Cancer: What Millennials and Gen Zers Need to Know
- Michigan Medicine: Colorectal Cancer Is No Longer Just a Disease of Older Adults
- Colon Cancer (Colorectal Cancer). Cleveland Clinic. October 28, 2025.
- Early-Onset Colon Cancer. Mayo Clinic. July 9, 2025.
- Colorectal Cancer Risk Factors. American Cancer Society.
- Ullah F et al. Early-Onset Colorectal Cancer: Current Insights. Cancers. June 15, 2023.
- Early-Onset Colorectal Cancer. Global Colon Cancer Association.
- APC I1307K and Colorectal Cancer. Johns Hopkins Medicine.
- Spander M et al. Young-onset colorectal cancer. National Review Disease Primers. April 27, 2023.
- Chen J et al. Environmental Drivers of the Rising Incidence of Early-Onset Colorectal Cancer in the United States. International Journal of Cancer. June 1, 2025.
- What Is the Link Between Obesity and Colorectal Cancer? Cancer Support Community. March 7, 2023.
- Hur J et al. Sugar-Sweetened Beverage Intake in Adulthood and Adolescence and Risk of Early-Onset Colorectal Cancer Among Women. Gut. May 6, 2021.
- Li H et al. Associations of smoking with early- and late-onset colorectal cancer. JNCI Cancer Spectrum. February 9, 2023.
- Johnson C et al. Molecular Mechanisms of Alcohol-Induced Colorectal Carcinogenesis. National Institutes of Health. August 31, 2021.
- Jin E et al. Sex and Tumor-Site Differences in the Association of Alcohol Intake With the Risk of Early-Onset Colorectal Cancer. Journal of Clinical Oncology. June 14, 2023.
- American Cancer Society Guideline for Colorectal Cancer Screening. American Cancer Society. January 29, 2024.
- Screening for Colorectal Cancer. Centers for Disease Control and Prevention. October 17, 2024.
- FDA Roundup. U.S. Food and Drug Administration. July 30, 2024.
- Doubeni CA et al. Effectiveness of Screening Colonoscopy in Reducing the Risk of Death from Right and Left Colon Cancer: A Large Community-Based Study. Gut. October 12, 2016.
- Comprehensive Metabolic Panel (CMP). Cleveland Clinic. July 3, 2024.
- CEA Test (Carcinoembryonic Antigen). Cleveland Clinic. June 5, 2025.
- Saraiva M et al. Early-Onset Colorectal Cancer: A Review of Current Knowledge. World Journal of Gastroenterology. February 28, 2023.
- Colon Cancer Treatment. Johns Hopkins Medicine.
- Kamath SD et al. Racial Disparities Negatively Impact Outcomes in Early‐Onset Colorectal Cancer Independent of Socioeconomic Status. Cancer Medicine. October 14, 2021.
- Zaki TA et al. Racial and Ethnic Disparities in Early-Onset Colorectal Cancer Survival. Clinical Gastroenterology and Hepatology. February 2023.
- Colon Cancer Treatment (PDQ®)–Health Professional Version. National Cancer Institute. September 6, 2024.
- AlZaabi A et al. Early Onset Colorectal Cancer: Challenges Across the Cancer Care Continuum. Annals of Medicine and Surgery. August 22, 2022.
- Kyrochristou ID et al. Early-Onset Colorectal Cancer in Patients Younger Than 50 Years: A Systematic Review of the Literature. Annals of Gastroenterology. June 25, 2025.
- Nors J et al. Risk of Recurrence in Early-Onset Versus Late-Onset Non-Metastatic Colorectal Cancer, 2004–2019: A Nationwide Cohort Study. The Lancet: Regional Health Europe. December 2024.
- Cheng E et al. Analysis of Survival Among Adults With Early-Onset Colorectal Cancer in the National Cancer Database. Clinical and Translational Gastroenterology. June 16, 2021.
- Colorectal Cancer. MedlinePlus. April 18, 2023.
- Metastasis. MedlinePlus. October 25, 2022.
- Living as a Colorectal Cancer Survivor. American Cancer Society. January 29, 2024.

Daniel Landau, MD
Medical Reviewer
Daniel Landau, MD, is a distinguished board-certified hematologist-oncologist with a career that has spanned two eminent institutions: the Orlando Health Cancer Institute and the M...

Don Rauf
Author
Don Rauf has been a freelance health writer for over 12 years and his writing has been featured in HealthDay, CBS News, WebMD, U.S. News & World Report, Mental Floss, United Press ...