Every year, more than 47,000 people learn that they have a cancer colorectal In France. Despite advances in treatments and the existence of a national screening program, this disease remains the third cause of cancer mortality, with around 17,000 deaths per year.
Definition: what is colon cancer? How does it start?
Colorectal cancer starts in the inner lining of the colon or rectum. In the majority of cases, it starts as a small polyp – a benign tumor located on the wall of the colon – which, over time, can become cancerous.
Colorectal cancer: what are the causes?
Several factors – heredity, lifestyle, etc. – increase the risk of developing colorectal cancer, in particular:
- smoking;
- regular alcohol consumption;
- excess of ultra-processed foods as well as red meat and charcuterie;
- overweight and lack of physical activity;
- chronic inflammatory bowel disease (IBD), particularly Crohn’s disease and ulcerative colitis;
– finally, certain rare genetic diseases strongly increase the risk of colorectal cancer, in particular Lynch syndrome.
« An American study (source 1) carried out on around 29,000 nurses over 24 years, showed that women consuming the most ultra-processed foods had an approximately 45% higher risk of developing early colorectal adenomas (precancerous polyps) compared to those who consumed little. », Specifies Dr Aude Guillemin. Work which reinforces the hypothesis of a link between diets rich in ultra-processed products and colorectal cancers.
Diarrhea, blood in the stools: what are the first symptoms of colon cancer?
Colorectal cancer can progress for a long time without causing symptoms.
Certain signs should nevertheless alert you, particularly when they persist or intensify:
- the presence of blood in the stools, bright red or darker;
- a lasting change in intestinal transit, such as diarrhea or unusual constipation;
- persistent abdominal pain;
- unexplained weight loss;
- unusual fatigue.
« A recent and lasting change in intestinal transit can be a warning sign, especially when it is accompanied by other symptoms such as blood in the stools or unusual fatigue. The problem is that many patients already suffer from functional digestive disorders with alternating diarrhea and constipation, which makes this sign difficult to interpret. », explains Dr Aude Guillemin. And to add: “ On the other hand, the presence of blood in the stools, even when it seems linked to hemorrhoids, should lead you to consult your doctor or a gastroenterologist in order to precisely identify the origin. »
Screening: how to detect colon cancer?
Organized screening for colorectal cancer is offered free every two years to people aged 50 to 74. Simple and quick to perform, this immunological test detects the presence of traces of blood in the stool, invisible to the naked eye, which may reveal a polyp or tumor. In the event of a positive result, a colonoscopy is prescribed to complete the examinations.
Colonoscopy, CT scan: how is colorectal cancer diagnosed
The diagnosis of colorectal cancer is based on colonoscopy. “This exam allows you to visualize the interior of the colon, identify polyps and remove them in order to have them analyzed, explains the specialist. If a cancerous lesion is identified, the gastroenterologist performs a biopsy and orders a thoraco-abdominopelvic CT scan to ensure that the disease is localized. »
Colorectal cancer: what is the treatment?
The treatment of colorectal cancer is mainly surgical. « When the disease is localized, treatment is based on surgery to remove the affected part of the colon or rectum as well as nearby lymph nodes.explains the oncologist. Depending on the anatomopathological analysis of the tumor, we will then decide whether or not to carry out additional chemotherapy to reduce the risk of recurrence. »
Prognosis: is colon cancer well treated?
Colorectal cancer has a good prognosis when it is diagnosed early enough. “When detected at an early and localized stage, the cure rate is very high, around 90%confirms Dr Aude Guillemin. Even when the disease is more advanced, treatments exist and today make it possible, in many cases, to significantly prolong survival while preserving a good quality of life.. »
Sources
Source 1 : Ultra-Processed Food Consumption and Risk of Early-Onset Colorectal Cancer Precursors among Women
