Colon cancer develops in the large intestine (colon), the lower part of your digestive system. Rectal cancer develops in the rectum, which makes up the last several inches of your intestinal tract. Together, they’re referred to as colorectal cancers.
Rectal cancer begins as small clumps of cells called polyps. Although most polyps are noncancerous (benign), some become cancerous over time. Regular screening to find and remove precancerous polyps can prevent rectal cancer from developing. Changes in your diet and lifestyle — such as healthy eating and increasing your physical activity — can help prevent polyps from forming, greatly reducing your risk of rectal cancer.
Rectal cancer often doesn’t cause symptoms in the early stages. The most common signs of the disease include:
- Rectal bleeding
- Changes in appetite and the frequency, consistency or size of bowel movements
- Unintended weight loss
- Extreme tiredness
Although many rectal cancers develop for reasons that aren’t well understood, certain factors increase your risk, including:
- Smoking
- Inflammatory bowel disease
- High-fat, low-fiber diet
- Inactive lifestyle
- Family history of rectal or colon canceror colorectal polyps
- Age older than 50 years
- Inherited gene mutations that lead to colorectal polyp formation
Treatment for rectal cancer varies, depending on how large the tumor has grown, how deeply it has invaded the wall of the rectum, and whether it has spread to the lymph nodes or other organs. Options include:
- Surgery – We perform most colorectal cancer surgeries usingminimally invasive (laparoscopic) surgery. Depending on the location and progression (stage) of your cancer, it may be treated with surgery alone or require a temporary or permanent colostomy — a small opening in your abdomen for eliminating waste.
- Chemotherapy and radiation therapy (chemoradiation).When rectal cancer has spread into surrounding tissue or lymph nodes. we recommend radiation therapyand chemotherapybefore surgery to help shrink the tumor, making it easier to perform the delicate surgery that preserves sphincter muscle and vital nerves. You may also receive chemoradiation after surgery, especially if cancer has spread to your lymph nodes. Chemotherapy drugs make cancer cells in the rectum more sensitive to radiation. Advanced technologies such as image-guided radiation therapy and intensity-modulated radiation therapy target tumors with great precision and reduce the chance of damage to nearby organs and bones.