Colorectal cancer is increasingly affecting younger adults across Asia and beyond. New research reveals rising diagnoses before age 50. This highlights the importance of recognising symptoms early and understanding who should consider screening.
For decades, colorectal cancer was considered a disease of older adults.
Today, that assumption no longer holds.
A report from the American Cancer Society suggests colorectal cancer is increasingly being diagnosed in younger adults. This reverses decades of progress in reducing the disease. Researchers warn that without greater awareness and earlier screening, more people may be diagnosed only after the cancer has already reached an advanced stage.
Published in CA: A Cancer Journal for Clinicians, the report found that adults under 65 now account for almost half of all new colorectal cancer cases in the United States. This marks a sharp increase from just over one-quarter in the mid-1990s.
Asia is seeing the same worrying pattern. A 2025 study published in the Journal of Gastroenterology and Hepatology found that Asia accounted for more than half (50.2%) of all colorectal cancer cases worldwide in 2022. The study estimated 966,400 new diagnoses and 462,300 deaths across the region.
Alarmingly, around 1 in 10 cases occurred in younger adults. Researchers reported that incidence is rising fastest among younger people and men. If current trends continue, the number of new colorectal cancer cases in Asia is projected to almost double to 1.87 million annually by 2050. In addition, there could be more than one million deaths. These findings highlight the growing need for earlier detection and stronger prevention efforts across the region.
A Worrying Shift Towards Younger Generations
While colorectal cancer rates continue to decline among adults aged 65 and above, the opposite trend is emerging in younger generations. Among adults aged 20 to 49, incidence is increasing by around 3% each year. Furthermore, rates are also continuing to climb, albeit more slowly, in adults aged 50 to 64.
According to Rebecca Siegel, senior scientific director of surveillance research at the American Cancer Society, the findings point towards a genuine increase in disease rather than simply better detection.
“After decades of progress, the risk of dying from colorectal cancer is climbing in younger generations of men and women.”
A study in 2025 by Singapore General Hospital and National Cancer Centre Singapore analysed more than 53,000 colorectal cancer cases recorded between 1968 and 2019. The researchers found that the incidence of early-onset colorectal cancer (diagnosed before the age of 50) has steadily increased over the past five decades.
Today, around 10% to 12% of colorectal cancer cases in Singapore occur in adults younger than 50, with specialists noting that younger patients are often diagnosed at a later stage because symptoms may be mistaken for less serious conditions such as haemorrhoids or irritable bowel syndrome.
Researchers believe environmental or lifestyle changes may be contributing, although the exact causes remain unclear.
The Challenge: Late Diagnosis
One of the biggest challenges is that colorectal cancer is often not suspected in younger people.
The report found that three out of four adults diagnosed before age 50 already have cancer that has spread beyond the bowel by the time it is discovered.
In comparison, when colorectal cancer is detected early and remains confined to the bowel, the five-year survival rate is approximately 95%.
Researchers also noted that half of colorectal cancer cases diagnosed before age 50 occur in people aged 45 to 49. This is an age group that is already eligible for screening under current US recommendations. Despite this, only around 37% are up to date with screening.
While the American Cancer Society recommends routine screening from 45 years old, Singapore currently recommends screening from 50 years old for people at average risk. However, the rising incidence of early-onset colorectal cancer may prompt future discussions about whether screening should begin earlier for some groups. This is especially important for those with a strong family history or other risk factors.
This suggests that improving participation in screening programmes could help detect more cancers before symptoms develop.
What Are The Warning Signs of Colorectal Cancer?
Many younger adults assume symptoms are caused by haemorrhoids, irritable bowel syndrome or stress, leading to delays in diagnosis.
Doctors recommend seeking medical attention if you experience:
- Blood in your stool or rectal bleeding
- Persistent changes in bowel habits
- Abdominal pain or persistent bloating
- Unexplained weight loss
- Ongoing fatigue or iron-deficiency anaemia
- A feeling that the bowel does not empty completely
These symptoms do not always mean cancer, but they should not be ignored, especially if they persist or worsen.
Can Colorectal Cancer be Prevented?
Researchers estimate that more than half of colorectal cancer cases may be linked to modifiable lifestyle factors. These include:
- Smoking
- Excess alcohol consumption
- Diets low in fibre and high in processed or red meat
- Physical inactivity
- Overweight and obesity
Regular screening through a colonoscopy also remains one of the most effective ways to prevent colorectal cancer. This is because it can detect and remove precancerous polyps before they become cancerous.
What Does This Mean For Us?
Although researchers are still trying to understand why colorectal cancer is becoming more common in younger adults, one message is increasingly clear: being young does not make you immune.
Persistent rectal bleeding, changes in bowel habits, unexplained weight loss, abdominal pain or ongoing fatigue should always be assessed by a healthcare professional. This is particularly true if symptoms persist or there is a family history of colorectal cancer.
As cases continue to rise among younger generations, recognising the warning signs early may be just as important as expanding access to screening.
