Colon Cancer

Colon cancer, also known as colorectal cancer, is a type of cancer that affects the large intestine (colon) or rectum. It occurs when abnormal cells in the colon or rectum grow and multiply uncontrollably, forming a tumor.

What is Colon Cancer?

Colon cancer is the third most common type of cancer in men and women, and it is the second leading cause of cancer deaths in the United States. The colon is a long, muscular tube that absorbs water and nutrients from food, while the rectum is the last part of the colon, where stool is stored until it is eliminated from the body.

Symptoms of Colon Cancer

The symptoms of colon cancer may vary depending on the location and size of the tumor. Common symptoms include:

• Blood in the stool or black, tarry stools
• Changes in bowel movements, such as diarrhea or constipation
• Abdominal pain or cramping
• Weakness or fatigue
• Loss of appetite
• Weight loss
• Nausea and vomiting

Risk Factors for Colon Cancer

Certain factors can increase a person's risk of developing colon cancer, including:

• Age: Most cases of colon cancer occur in people over the age of 50
• Family history: Having a family history of colon cancer or polyps
• Diet: A diet high in red meat and low in fiber
• Obesity: Being overweight or obese
• Lack of physical activity: Not getting enough exercise
• Smoking: Smoking cigarettes
• Previous radiation therapy: Having had previous radiation therapy to the abdomen

Diagnosis of Colon Cancer

Colon cancer is typically diagnosed using a combination of tests, including:

• Colonoscopy: A procedure in which a flexible tube with a camera and light on the end is inserted into the rectum to visualize the colon
• Biopsy: A sample of tissue is removed from the colon or rectum and examined under a microscope for cancer cells
• Imaging tests: Such as CT scans, MRI scans, or PET scans to determine the extent of the cancer
• Stool tests: Such as fecal occult blood tests (FOBT) or stool DNA tests to detect blood or abnormal cells in the stool

Treatments for Colon Cancer

The treatment for colon cancer depends on the stage and location of the tumor, as well as the overall health of the patient. Common treatments include:

• Surgery: To remove the tumor and surrounding tissue
• Chemotherapy: To kill cancer cells that have spread to other parts of the body
• Radiation therapy: To kill cancer cells in the colon or rectum
• Targeted therapy: To target specific genes or proteins that are involved in the growth and spread of cancer cells
• Immunotherapy: To stimulate the immune system to attack cancer cells

Stages of Colon Cancer

Colon cancer is typically staged using the TNM system, which takes into account the size and location of the tumor (T), the spread of cancer to nearby lymph nodes (N), and the presence of distant metastasis (M). The stages of colon cancer are:

• Stage 0: Cancer is limited to the lining of the colon or rectum
• Stage I: Cancer has grown into the wall of the colon or rectum, but has not spread to lymph nodes or distant sites
• Stage II: Cancer has grown through the wall of the colon or rectum and may have spread to nearby tissues, but has not spread to lymph nodes or distant sites
• Stage III: Cancer has spread to nearby lymph nodes, but has not spread to distant sites
• Stage IV: Cancer has spread to distant sites, such as the liver, lungs, or peritoneum

Prevention of Colon Cancer

While there is no sure way to prevent colon cancer, certain lifestyle changes and screening tests can help reduce the risk. These include:

• Eating a healthy diet high in fiber and low in red meat
• Getting regular exercise
• Maintaining a healthy weight
• Not smoking
• Limiting alcohol consumption
• Getting screened for colon cancer regularly, starting at age 50