Colorectal cancer – the third most common form of cancer

Colon and rectal cancer (colorectal cancer; CRC, eng. colorectal cancer), is a form of cancer that arises from uncontrolled cell growth in the colon, rectum or appendix.

The disease often develops slowly for several years. It begins as a protruding tissue growth, called a polyp, that starts out in the mucus membrane and then grows into the intestinal cavity. Polyps can be cancerogenic, meaning they can develop into a cancer if they are not removed. Eventually, the cancer can break through the intestinal wall and spread to other organs. This is known as metastatic colorectal cancer, or mCRC.

Third most common cancer

Colorectal cancer is the third most common cancer diagnosis globally after lung and breast cancer, and the second deadliest. It affects both men and women with an equal distribution between the genders. However, there are differences in its localization, as more men are affected by rectal cancer and more women by colon cancer. CRC mainly affects older people, with the majority becoming ill after the age of 70. The global incidence (the number of new patients who are diagnosed with this form of cancer annually) was just over 1,9 million patients a year in 2022, while about 0.9 million died from the disease that year¹.

The causes are partly environmental and hereditary

As with most other forms of cancer, there is no single known triggering factor for CRC. It is believed that the risk can be affected by diet and hereditary factors. Smoking and lifestyles leading to obesity also increase the risk.

High mortality rates in case of late detection

Colorectal cancer is globally the second most common cause of cancer-related deaths after lung cancer. However, the prognosis for survival is better with an early diagnosis. Through health checks, by screening stool samples for blood, colorectal cancer can be detected at an early stage, which reduces mortality. Patients who are detected in a late stage, when the cancer has spread to other organs (metastases), have a worse prognosis and significantly higher mortality. Just under 16 percent of patients with mCRC are alive five years after diagnosis².

Source: 1) Ferlay J, Ervik M, Lam F, Laversanne M, Colombet M, Mery L, Piñeros M, Znaor A, Soerjomataram I, Bray F (2024). Global Cancer Observatory: Cancer Today (version 1.1). Lyon, France: International Agency for Research on Cancer. Available from: https://gco.iarc.who.int/today, accessed [27 March 2024].
2) SEER*Explorer: An interactive website for SEER cancer statistics [Internet]. Surveillance Research Program, National Cancer Institute; 2023 Apr 19. [updated: 2023 Nov 16; cited 2024 Mar 27]. Available from: https://seer.cancer.gov/statistics-network/explorer/.

Last updated 05-15-2024