Colon Cancer
What Is Colon Cancer?
Colon cancer is a type of cancer that begins in the colon (large intestine) — the final part of the digestive tract. Most colon cancers start as small growths called polyps on the inner lining of the colon. Over time, some polyps can become cancerous. When detected early, colon cancer is highly treatable, but when advanced it can spread to other organs and become more difficult to manage.
Colon cancer is one of the most common cancers affecting both men and women. Because early stages may not cause symptoms, routine screening is a key part of prevention and detection.
Causes and Risk Factors
Colon cancer results from genetic changes in colon cells that cause them to grow uncontrollably. While the exact cause of these changes is not always known, several factors increase the risk:
- Age — risk increases after age 50
- Family history of colon cancer or polyps
- Inherited syndromes such as Lynch syndrome or familial adenomatous polyposis
- Personal history of inflammatory bowel disease (such as Crohn’s or ulcerative colitis)
- Diet high in red or processed meats and low in fiber
- Sedentary lifestyle, obesity, smoking, and heavy alcohol use
Because many of these factors are common, screening plays a critical role in early detection and improved outcomes.
Signs and Symptoms
Early colon cancer may not cause noticeable symptoms. When symptoms occur, they often develop gradually and may include:
- A persistent change in bowel habits (diarrhea or constipation)
- Blood in the stool or rectal bleeding
- Unexplained weight loss
- Persistent abdominal discomfort, cramps, or gas
- Weakness or fatigue
- A feeling that the bowel does not empty fully
These symptoms can also be associated with other, less serious conditions. However, any persistent or worsening symptoms should prompt medical evaluation.
Diagnosis
Diagnosing colon cancer typically involves a combination of clinical assessment and diagnostic testing:
- Colonoscopy — direct visualization of the entire colon and removal of polyps
- Biopsy — laboratory analysis of tissue samples to confirm cancer
- Imaging studies such as CT scans to assess cancer spread
- Blood tests including markers that may support diagnosis and staging
Colonoscopies can both detect early cancer and remove polyps before they become cancerous, making them a powerful tool for both prevention and diagnosis.
Treatment Options
Treatment depends on the stage of cancer, location of the tumor, and overall health. Common options include:
- Surgery to remove the cancerous portion of the colon and nearby lymph nodes
- Minimally invasive surgery using laparoscopic or robotic techniques when appropriate
- Chemotherapy before or after surgery to destroy cancer cells
- Targeted therapy or immunotherapy for advanced or specific types of colon cancer
- Radiation therapy in select cases
A multidisciplinary approach — coordinated among surgeons, medical oncologists, and radiation specialists — ensures the best plan for each patient.
