Colon cancer, also known as colorectal cancer, is one of the most common types of cancer worldwide. This cancer develops in the cells of the colon, which is the lower part of the intestine.

Colorectal cancer usually starts as a polyp on the inner lining of the colon or rectum. These polyps can turn into cancer over time. While there are several risk factors for colon cancer, such as age, obesity, and smoking, genetics also plays a significant role in its onset.

The Genetics of Colon Cancer

One of the genes that can increase a person’s risk of colon cancer is the adenomatous polyposis coli (APC) gene. This gene is responsible for producing a protein that helps prevent the formation of polyps in the colon.

When a person has a mutation in the APC gene, it can lead to the development of multiple polyps in the intestine, which can increase the risk of colon cancer. The APC gene is inherited in an autosomal dominant pattern, which means that a person only needs to inherit one mutated copy of the gene from either parent to be at risk of developing colon cancer.

Another gene associated with colon cancer is the DNA mismatch repair (MMR) gene. MMR genes are responsible for correcting errors that occur during DNA replication.

When there is a mutation in one of these genes, it can lead to an accumulation of DNA errors, which can increase the risk of colon cancer. This type of colon cancer is known as hereditary nonpolyposis colorectal cancer (HNPCC), or Lynch syndrome.

Other genes associated with colon cancer include KRAS, BRAF, PIK3CA, and TP53. Mutations in these genes can cause uncontrolled cell growth, which can lead to the development of cancer.

Colon Cancer Screening

Colon cancer is one of the most preventable types of cancer, as early detection can improve the chance of successful treatment. Doctors recommend regular colon cancer screening for people over the age of 50.

Screening tests can detect polyps in the colon before they become cancerous, allowing for early intervention.

The most common type of colon cancer screening is a colonoscopy, which allows doctors to examine the entire colon and remove any polyps that are found.

Other types of screening tests include stool tests, such as fecal immunochemical tests (FIT), and virtual colonoscopies.

Genetic Testing for Colon Cancer

Genetic testing can help identify people who are at increased risk of developing colon cancer. This testing can be done on a blood or saliva sample and can detect mutations in genes associated with colon cancer.

People who have a family history of colon cancer, particularly those with a first-degree relative (such as a parent or sibling) who has had the disease, may be candidates for genetic testing.

This testing can help identify if they have inherited a mutation in a colon cancer gene and can inform decisions about surveillance and treatment.

Treatment for Colon Cancer

The treatment for colon cancer depends on the stage of the cancer, as well as the person’s overall health. Treatment options include surgery, chemotherapy, and radiation therapy.

Surgery is the most common treatment for colon cancer and involves removing the tumor and any surrounding lymph nodes. In some cases, a colostomy (an opening in the abdomen for waste removal) may be necessary.

Chemotherapy uses drugs to kill cancer cells and is often used after surgery to kill any remaining cancer cells. Radiation therapy uses high-energy rays to kill cancer cells and is often used in combination with chemotherapy.

Preventing Colon Cancer

While genetics plays a significant role in the development of colon cancer, making lifestyle changes can help reduce the risk. These changes include:.

Having a healthy diet that is high in fiber and low in red and processed meat
Maintaining a healthy weight
Exercising regularly
Avoiding smoking and excessive alcohol consumption

Another way to prevent colon cancer is through regular screening tests, which can detect and remove polyps before they turn into cancer.

People with a family history of colon cancer or other risk factors should talk to their doctor about when to start screening and how often to get screened.

Conclusion

Colon cancer is a common and potentially lethal disease that is influenced by genetics. The APC and MMR genes, along with other genes, can increase a person’s risk of developing colon cancer.

Screening tests, genetic testing, and lifestyle changes can help prevent colon cancer or detect it early when it is most treatable.