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Colorectal cancer: Causes and treatment

Colorectal Cancer : Causes and Treatment

Colorectal cancer is the type of cancer that affects the human colon or large intestine. Extending from the end of the small bowel to the rectum, this muscular, tube-shaped organ digests and absorbs nutrients from food, concentrates faecal matter by absorbing fluid, and stores and controls the evacuation of faeces.

Cancer in this region of the body transforms normal cells until they grow and multiply. In the absence of effective treatment, cancer spreads through the colon wall to the adjacent lymph nodes and organs. It can then metastasise to major organs including the liver, brains, lungs, and bones.

This blog dives into the causes of colorectal cancer and treatment. Patients who suspect that they may be experiencing symptoms of this condition should receive medical attention immediately.

The causes and risk factors of colorectal cancer


Colorectal cancer can be contracted as a result of inherited genes and shared environmental factors. For patients with family members with this condition, a colonoscopy will be recommended to screen for polyps, perhaps much earlier compared to other patients.

Inherited syndromes

Colorectal cancer has been associated with certain inherited conditions including familial adenomatous polyposis (FAP) and hereditary non-polyposis colorectal cancer (HNPCC). Patients with Lynch Syndrome, Turcot Syndrome, and Peutz-Jeghers Syndrome may also be more vulnerable to the onset of this type of cancer.

Racial factors

Individuals belonging to certain races, including African Americans living in the US and Ashkenazi Jews, are believed to be at higher risk of developing colorectal cancer. These individuals are advised to remain proactive about cancer screening relatively early on in their lives.

Lifestyle factors

Individuals who maintain a diet high in red and processed meat may also be at increased risk of developing this type of cancer. Cooking meat at a high temperature produces chemicals that may increase this risk even further.

A lack of exercise is a contributory factor as is smoking and frequent alcohol consumption. Obesity increases this risk.


While individuals can contract colorectal cancer at any age, the risk is higher after the age of 45. A significant majority of those with this condition are over this age.

History of colorectal cancer

For patients who have developed this condition in the past, it is possible that this condition can reoccur in the same area or close to where the original tumour formed. Patients who have bowel polyps are also more at risk of developing this condition, even if the polyps were removed or proved to be benign.

Inflammatory Bowel Disease (IBD)

IBD, ulcerative colitis, and Crohn’s disease increase the risk of colorectal cancer. Depending on how long a patient suffers from this condition and how badly the colon is affected, the risk may increase.

Treatments for colorectal cancer


Patients who undergo surgery as a part of their treatment plan are subjected to the removal of tumours, lymph nodes, the affected sections of the colon, and the reattachment of healthy ends of the intestines. Sometimes, the entire colon is removed.

Surgery can be combined with chemotherapy, both before or after the surgery.


Medication that’s referred to as checkpoint inhibitors may be used to treat cases where colorectal cancer has specific genomic features. Specifically, patients with inoperable metastatic tumours with microsatellite instability-high (MSI-H) or mismatch repair deficiency (dMMR) genetic features may be most suitable for this type of immunotherapy.


Chemotherapy aims to destroy cancer cells or prevent them from growing and reproducing. Despite its popularity, it may not be recommended for every patient with colorectal cancer. It may be administered intravenously or in the form of pills.

Chemotherapy can be further broken down into neoadjuvant chemotherapy (administered before surgery) and adjuvant chemotherapy (administered after surgery).

Radiation therapy

Radiation therapy may be administered before or after a surgery or even as one of the primary treatment methods for patients who cannot undergo surgery.

Targeted therapy

Monoclonal antibody therapy is a type of targeted therapy used to treat this condition. The antibodies are proteins that are bio-engineered to help a patient’s immune system attack and destroy colorectal cancer cells.

This form of therapy may be used in isolation or together with other treatments.

Patients must receive treatment for colorectal cancer from experienced gastroenterologists

With the five-year survival rate for this condition at 69%, colorectal cancer does not have to result in serious consequences if the appropriate action is taken.

Given that prevention is the best strategy, patients are advised to undergo frequent cancer screenings after the age of 45 to reduce their risk. Those displaying symptoms of this condition or who have already been diagnosed with colorectal cancer must seek expert gastroenterological treatment.