Colorectal cancer begins when cells in the colon or rectum, start to divide uncontrollably and form a tumour. The most common forms start as polyps, small benign growths on the lining of the bowel, which can sometimes develop into malignant tumours.

Symptoms may include:

  • Changes in bowel habits (diarrhoea or constipation)
  • Blood in the stool or dark stools
  • Feeling of incomplete emptying
  • Weakness, fatigue or anaemia
  • Unexplained weight loss

Important: In the early stages, there may be no symptoms.

Risk factors for CRC include:

  • Age over 45
  • Family history of colorectal cancer
  • History of inflammatory bowel disease (e.g. ulcerative colitis, Crohn’s disease)
  • A diet high in fat and low in fibre
  • Smoking, alcohol, sedentary lifestyle

Colorectal cancer (CRC) is a type of cancer that can be detected early. Early diagnosis, mainly through screening, has been shown to reduce both the number of new cases and mortality, especially in countries with organised prevention programmes.

In areas with a high incidence of CRC, systematic screening has significantly helped to:

  • Reducing the incidence of the disease through early detection and removal of precancerous lesions, such as adenomatous polyps.
  • Reducing mortality, as cancer is diagnosed at an early stage, when treatment is most effective.
  • Increase cost-effectiveness, since early diagnosis lowers the need for expensive treatments in advanced stages.

Colorectal cancer is the third most common cancer worldwide after breast and lung cancer and the second most common cause of cancer deaths.

Approximately 2 million new cases are diagnosed globally each year, with more than  900,000 deaths. Colorectal cancer occurs more frequently in men and is increasing in prevalence in Western countries.

According to the World Health Organisation (WHO), within the next 15 years, the number of new cases per year is expected to reach 3.5 million, with deaths approaching 1.5 million (an increase of over 70%).  It is particularly concerning that cases of colorectal cancer in young adults (<50 years old) are increasing by about 3% and are often diagnosed at an advanced stage.

Today, there are various methods of preventive screening, such as colonoscopy and faecal immunochemical tests occult blood (e.g. FIT). However, in Greece, only about 25% of people aged 45-50 and older participate in the recommended screening, well below the target of 80%. Moreover, around 76% of deaths from CRC occur among people who have never undergone preventive screening.

This highlights the urgent need for diagnostic tests that are more accessible, simple and acceptable to the public, in order to increase participation and cover a larger proportion of the population.

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