Bowel cancer (colorectal cancer)
Colorectal cancer (commonly Bowel cancer) is where the large intestine, the last 1.5 metres of the gastrointestinal tract, is affected by cancerous diseases.
It mostly develops with people past the age of 50, while it very rarely affects younger people. In Europe there are almost 38,000 new cases discovered yearly, which means that colorectal cancer is one of the most frequent cancerous diseases. The survival of patients suffering from colorectal cancer improves yearly. This is mostly due to improved operating techniques and the systemic treatment of the disease with medications which are becoming increasingly effective.
The disease develops as a consequence of genetic and environmental factors
The cause for the disease’s appearance is still unknown; however it is known that colorectal cancer occurs as a consequence of the combined functions of hereditary and environmental factors. The risk of developing the disease is increased by an unhealthy lifestyle and the ingestion of fat food as well as alcohol, smoking, colorectal polyps and chronic inflammatory diseases. If the disease is present in the family, the risk of developing it is doubled.
Colorectal cancer usually develops as a reaction to polyps (an abnormal growth of tissue projecting out of a mucous membrane). Polyps mostly grow on the colon or rectum wall. Smaller polyps do not cause difficulties, while the bigger ones can cause cramps, hard constipation, bleeding, abdominal pain or even a complete intestinal blockage.
Clinical symptoms depend on the size, location and the tumour’s expansion. They are frequently followed by abdominal pain, nausea and vomiting, digestive disorders and a feeling of bowels being never emptied, anaemia and the loss of appetite. Numerous patients confuse early symptoms with other digestive disorders. This is why the disease is mostly discovered in its already progressed phase, when the prognosis is poor.
Prevention and therapy
The main reasons for the development of colorectal cancer in the developed world are the ageing of the population, the lack of physical activity and the ingestion of unhealthy foods. It has been proved that regular exercise, maintenance of normal weight, avoidance of excessive alcohol intake and smoking significantly reduce the risk for developing the disease.
It is advisable to consume a varied diet with a lot of fruits and vegetables. Food high in fibres increases stool volume and shortens the transit time of digested contents through the intestine. This enables the intestinal mucosa to be in contact with cancerous substances and some bile acids for a shorter period of time.
It is recommended to drink alcohol in moderation (men: 2dcl wine/day, women: 1dcl wine/day) and to avoid active and passive smoking.
The main factor for developing colorectal cancer is ageing. Before the age of 50 the disease affects only 10% of the population, which means that 90% of patients are between the ages of 50 and 70. The preventive measures are therefore recommended for the entire population. If colorectal cancer is discovered early, there is a great possibility of recovery. This is why more and more countries are introducing national programs for discovering colorectal cancer.
The first phase of the disease treatment consists of a surgical removal procedure of the cancerous tissue. Treatment with radiation, i.e. radiotherapy, is used only before the surgery and for advanced phases when the tumour has already ingrown into the muscle layers and the surrounding brown fat. The systemic treatment of colorectal cancer by using medications (chemotherapy, biological medications) is performed as an additional treatment after the surgery, or when the disease has already spread.