What is colorectal cancer?

Image of Colorectal Cancer

Colorectal cancer is the uncontrolled growth of malignant cells in the rectum or colon (large intestine). It is the second most common cancer site (following lung) in the U.S.. It may involve anywhere along the large intestine with approximately 70% of all cancers occurring below the midpoint of the descending colon (descending 10%; sigmoid 10%, rectum 50%) and the remainder in the cecum, ascending colon, transverse colon, and upper descending colon (29.5%). It most often affects adults over 40.

What are the signs of colorectal cancer?

Colorectal cancer frequently presents with no symptoms at all in the early stages. If it presents at the later stages, the following symptoms may be present:

What causes colorectal cancer?

Image of Female Surgeon Holding Blue Ribbon in Honor of Colon Cancer Awareness

The cause of colorectal cancer is mostly unknown although both genetic and environmental factors may contribute.

Risk increases with Adults over 50:

Preventative measures

Expected outcome

Overall outlook is variable depending on the stage the disease has reached when it is discovered. More than 50% of patients survive 5 years after surgery. The earlier the tumor is detected, the greater the chances for full recovery following treatment.

Possible complications

Spread to other body parts and death. Complications of surgery (infection, pneumonia, abscess).

How is colorectal cancer treated?

When you see a specialist, you will have an evaluation done which would include:


Surgery to remove the tumor. It is sometimes necessary to divert the bowel through a surgical opening in the abdomen (colostomy). If you have a colostomy, you will require special instructions for care of the opening.

Additional treatments

Sometimes, chemotherapy and/or radiation therapy may be necessary to treat the colorectal cancer before or after surgery. This decision is made with the help of Oncology and Radiation specialists.

When should I see/notify the specialist?

If you or a family member has symptoms of cancer of the large intestine, especially rectal bleeding or a significant change in bowel habits that lasts longer than 7 days. Also if symptoms of anemia develop (fatigue, paleness and rapid heartbeat).