Colorectal cancer, which affects the colon and rectum, is one of the most common cancers globally, yet it can remain unnoticed for a long time because some people have no symptoms in the early stages.
The World Health Organisation (WHO) estimates that 1.9 million new cases of colorectal cancer and more than 900,000 deaths occurred globally in 2022.
The agency said symptoms, when they occur, may include blood in the stool, persistent changes in bowel habits, abdominal pain, unexplained weight loss and fatigue.
Because some people may not notice any warning signs, screening can provide an opportunity to identify possible abnormalities before the disease becomes advanced.
What happens before a diagnosis is confirmed?
