Diagnosing Colorectal Cancer: Debunking 5 Persistent Myths

Many young adults mistakenly believe that the possibility of colorectal cancer is only a concern for older individuals. However, in reality, one in five new cases of colorectal cancer now occurs in people under 55 years of age—and this rate has, according to the American Cancer Society (ACS), nearly doubled since 1995, rising from 11% in 1995 to 20% in 2019.[1] Furthermore, the triennial ‘Colorectal Cancer Statistics (2026)’ report, published earlier this year, shows that although the disease continues to decline among older adults, rates are rising among people under 65, particularly younger adults. At the same time, colorectal cancer death rates increased by 1% annually in people younger than 50 years of age and by 0.6% annually in people ages 50-54 since about 2005, making it the third most common cancer in the United States.[1][2]

Dismissing early symptoms of colorectal cancer (colon or rectal) due to a perceived lack of risk can delay diagnosis and treatment, allowing the disease to advance. Because colorectal cancer is a potentially preventable cancer, it is important to be screened regularly. A 2011 study suggests that >95% of cases of colorectal cancer would benefit from curative surgery if diagnosis were made at an early or premalignant polyp stage of disease. [3][4] That’s why it’s important for people in their 40s, 30s, and even 20s to understand the facts about colorectal cancer.

Anju M. Malieckal, MD, is a gastroenterologist at NYU Langone Health in New York, NY. She provides care that emphasizes both medical and lifestyle interventions, including preventive colorectal cancer screening. In our interview, she addresses five common myths younger adults should know and understand about colorectal cancer:

Myth 1: I’m Too Young for Colorectal Cancer
The incidence of colorectal cancer in people under 50 is rising, prompting the U.S. Preventive Services Task Force to lower the recommended screening age to 45, suggesting that ‘Forty-Five Is the New Fifty.’ [5][6]

Malieckal explains that most cases in younger adults are not due to inherited genetic disorders but develop from polyps that gradually change over time. Lifestyle and environmental factors—such as smoking, alcohol use, excess weight, inactivity, and diets low in fiber and high in red and processed meats—are linked to increased risk. The gut microbiome, insulin resistance, and ultra-processed foods are also being studied as possible contributors. Ignoring symptoms like rectal bleeding or fatigue can give the cancer time to progress.

“Many people think, ‘I’m young and healthy, so I don’t need to worry.’  That mindset needs to change,” Malieckal added.

Myth 2: Rectal Bleeding Is Always Hemorrhoids
While hemorrhoids are common and usually harmless, rectal bleeding is also one of the most frequent early signs of colorectal cancer.

“People often attribute intermittent rectal bleeding to hemorrhoids,” Malieckal noted. “However, you can’t distinguish between hemorrhoid-related and cancer-related bleeding without proper evaluation. So that’s why any episode of rectal bleeding warrants a visit to your doctor,” she explained

“Never ignore rectal bleeding or blood in your stool,” Malieckal emphasized. “And…always mention new or persistent symptoms to your physician,” she said.

Myth 3: Fatigue and Bowel Changes Are Just Stress or IBS
Fatigue is easily blamed on stress or a busy lifestyle, and changes in digestion may be written off as irritable bowel syndrome (IBS). But when symptoms persist, especially alongside unexplained weight loss, they require medical attention. Another warning sign is unexplained anemia, which, while common in menstruating women, is less typical in younger men and may indicate intestinal blood loss.

“Anytime I see a young male patient with anemia, it’s a red flag,” Malieckal warned.

Myth 4: At-Home Screening Tests Are as Good as Colonoscopy
While they are non-invasive and readily accessible, at-home stool tests such as Cologuard and FIT (fecal immunochemical test) are convenient but have limitations.*

“They’re helpful, good tests, but not necessarily 100% accurate,” Malieckal explained.

False positives and false negatives can occur, and not everyone qualifies for these tests. If a stool test is abnormal, a follow-up colonoscopy is necessary. People with a family history of colorectal cancer or polyps, rectal bleeding, inflammatory bowel disease, or symptoms suggestive of colorectal cancer should skip at-home testing and go straight to a colonoscopy. Today, a colonoscopy still remains the gold standard because it can diagnose and treat—finding and removing pre-cancerous polyps in a single procedure. Most people should begin screening at 45, but those with elevated risk should talk to their doctor about starting earlier. Any concerning symptoms at any age should prompt a visit to a primary care doctor or gastroenterologist.

Myth 5: Being Young Means a Worse Prognosis
Colorectal cancer isn’t necessarily more aggressive in younger individuals; rather, it’s often diagnosed at a later stage because symptoms are overlooked. Early detection is crucial. Healthy young adults tend to respond well to modern treatments, including immunotherapy, targeted therapies, and minimally invasive surgery. NYU Langone Health’s Early Onset Cancer Program offers personalized treatment for adults under 50, while the Survivorship Program at Perlmutter Cancer Center supports patients during and after treatment. “Today’s treatments help patients maintain a good quality of life—even while undergoing therapy,” says Dr. Malieckal.

Lowering risk
Colorectal cancer cannot be prevented in all cases. But people can take important steps to help them lower their risk and catch the disease in an early stage, when it is easier to treat:

• Stay active: Regular exercise lowers colorectal cancer risk; even brisk walking helps.
• Eat well: Prioritize fiber, limit alcohol and red meat, and reduce processed foods.
• Know your family history: Awareness of relatives with cancer or polyps can help determine your risk and appropriate screening times.
• Listen to your body: Don’t ignore rectal bleeding, changes in bowel habits, unexplained anemia, persistent bloating, abdominal discomfort, fatigue, or unintentional weight loss—speak to your doctor.

For people 45 or older, schedule a screening colonoscopy. But at any age, see a doctor if you experience symptoms. Early evaluation may include a colonoscopy, which can be life-saving. To find a gastroenterologist or learn more about screening and prevention.

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Note: Cologuard® (Exact Sciences) is a noninvasive test with 92% sensitivity for detecting colorectal cancer. However, it must be repeated every three years and is FDA-approved only for individuals at ‘average risk’ of colorectal cancer. Cologuard is not recommended for those with a family history of colon cancer or polyps, or a personal history of polyps. Its sensitivity for detecting advanced precancerous polyps is relatively low at 42%, and it can miss about 8% of colorectal cancers. Additionally, Cologuard has a high false positive rate, meaning any positive result requires follow-up with a colonoscopy for further evaluation. Cologuard is, however, typically more sensitive than FIT for detecting colorectal cancer and offers greater specificity (around 95%) compared to Cologuard (approximately 87–91%), meaning it produces fewer false positives. FIT tests are performed annually to detect blood in the stool.

Reference
[1] Colorectal Cancer, Facts & Figures 2023-2025. American Cancer Society (ACS). Online. Last accessed in March 2026.
[2] Siegel RL, Wagle NS, Star J, Kratzer TB, Smith RA, Jemal A. Colorectal cancer statistics, 2026. CA Cancer J Clin. 2026 Mar-Apr;76(2):e70067. doi: 10.3322/caac.70067. PMID: 41769777.
[3] Pawa N, Arulampalam T, Norton JD. Screening for colorectal cancer: established and emerging modalities. Nat Rev Gastroenterol Hepatol. 2011 Nov 1;8(12):711-22. doi: 10.1038/nrgastro.2011.205. PMID: 22045159.
[4] Tsukanov VV, Vasyutin AV, Tonkikh JL. Risk factors, prevention and screening of colorectal cancer: A rising problem. World J Gastroenterol. 2025 Feb 7;31(5):98629. doi: 10.3748/wjg.v31.i5.98629. PMID: 39926213; PMCID: PMC11718609.
[5] US Preventive Services Task Force; Davidson KW, Barry MJ, Mangione CM, Cabana M, Caughey AB, Davis EM, Donahue KE, Doubeni CA, Krist AH, Kubik M, Li L, Ogedegbe G, Owens DK, Pbert L, Silverstein M, Stevermer J, Tseng CW, Wong JB. Screening for Colorectal Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2021 May 18;325(19):1965-1977. doi: 10.1001/jama.2021.6238. Erratum in: JAMA. 2021 Aug 24;326(8):773. doi: 10.1001/jama.2021.12404. PMID: 34003218.
[6] Ng K, May FP, Schrag D. US Preventive Services Task Force Recommendations for Colorectal Cancer Screening: Forty-Five Is the New Fifty. JAMA. 2021 May 18;325(19):1943-1945. doi: 10.1001/jama.2021.4133. PMID: 34003238.

Featured image: Physician consulting with a patient in a hospital exam room. Photo courtesy © 2019 – 2026 Fotolia/Adobe. Used with permission.

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