Colorectal Cancer

Colorectal Cancer is the second most common cancer in the United
States, striking 140,000 people annually and causing 60,000 deaths. That’s a staggering figure when you consider the disease is potentially curable if diagnosed in the early stages.

Who is at risk?

Though colorectal cancer may occur at any age, more than 90% of the patients are over age 40, at which point the risk doubles every ten years. In addition to age, other high risk factors include a family history of colorectal cancer and polyps and a personal history of ulcerative colitis, colon polyps or cancer of other organs, especially of the breast or uterus.

How does it start?

It is generally agreed that nearly all colon and rectal cancer begins in benign polyps. These pre-malignant growths occur on the bowel wall and may eventually increase in size and become cancer. Removal of benign polyps is one aspect of preventive medicine that really works!

What are the symptoms?

The most common symptoms are rectal bleeding and changes in bowel habits, such as constipation or diarrhea. (These symptoms are also common in other diseases so it is important you receive a thorough examination should you experience them.) Abdominal pain and weight loss are usually late symptoms indicating possible extensive disease.

Unfortunately, many polyps and early cancers fail to produce symptoms. Therefore, it is important that your routine physical includes colorectal cancer detection procedures once you reach age 50. There are several methods for detection of colorectal cancer. These include digital rectal examination, a chemical test of the stool for blood, flexible sigmoidoscopy and colonoscopy (lighted tubular instruments used to inspect the lower bowel) and barium enema. Be sure to discuss these options with your surgeon to determine which procedure is best for you. Individuals who have a first-degree relative (parent or sibling) with colon cancer or polyps should start their colon cancer screening at the age of 40.

How is colorectal cancer treated?

Colorectal cancer requires surgery in nearly all cases for complete cure. Radiation and chemotherapy are sometimes used in addition to surgery. Between 80-90% are restored to normal health if the cancer is detected and treated in the earliest stages. The cure rate drops to 50% or less when diagnosed in the later stages. Thanks to modern technology, less than 5% of all colorectal cancer patients require a colostomy, the surgical construction of an artificial excretory opening from the colon.

Can colon cancer be prevented?

Colon cancer is preventable. The most important step towards preventing colon cancer is getting a screening test.  Any abnormal screening test should be followed by a colonoscopy. Some individuals prefer to start with colonoscopy as a screening test.

Colonoscopy provides a detailed examination of the bowel. Polyps can be identified and can often be removed during colonoscopy.

Though not definitely proven, there is some evidence that diet may play a significant role in preventing colorectal cancer. As far as we know, a high fiber, low fat diet is the only dietary measure that might help prevent colorectal cancer.

Finally, pay attention to changes in your bowel habits. Any new changes such as persistent constipation, diarrhea, or blood in the stool should be discussed with your physician.

Can hemorrhoids lead to colon cancer?

No, but hemorrhoids may produce symptoms similar to colon polyps or cancer. Should you experience these symptoms, you should have them examined and evaluated by a physician, preferably by a colon and rectal surgeon.

Genetics and Colorectal Cancer 

What does genetics have to do with colon and rectal cancer?

Genes are the biochemical information that we inherit from each of our parents. They determine our varied physical features and may predispose us to certain diseases. Probably all cancers, especially colon and rectal cancer (CRC), have hereditary genetic factors that potentially increase an individual’s risk to developing these malignancies. In other words, genes are the reason why some diseases such as CRC occur more frequently in certain families. For this reason, when visiting a colon and rectal surgeon, it is important to provide a detailed family history with regard to cancer.

Are there different types of colon and rectal cancer?

From a genetic perspective, there are three broad classifications of CRC. The table below shows the respective proportion of each different classification.

Sporadic Colon Cancer 50% to 60%
Familial Colon Cancer 30% to 40%
Inherited Colon Cancer Syndromes 4% to 6%

 

What is sporadic colon cancer?

Sporadic colon cancer generally occurs in someone over age 60, without a prior family history of CRC. One in eighteen Americans will develop CRC. Patients who develop CRC as the first member of their family should be encouraged to inform relatives. People with a family history of colon rectal cancer should be advised to inquire about screening protocols at an earlier age.

What is familial colon cancer?

Some families are predisposed to getting colon cancer. There should be concern if a family has more than one relative with CRC, especially if the CRC occurred in an individual before age 50. If a first degree relative (parent, sibling, or child) develops a colorectal cancer, the risk of family members developing this disease is doubled. Individuals with a first degree relative who has been diagnosed with CRC should begin colon cancer screening at 40 years of age or 10 years earlier than the age at which their relative was diagnosed with cancer, whichever is earlier.

What are hereditary colorectal cancers?

Hereditary colorectal cancers are associated with a specific genetic abnormality. As genetic researchers continue to define certain syndromes, more genes that predispose colorectal cancer will likely be identified. Currently, some of the syndromes include:

  • HNPCC (Hereditary Non-Polyposis Colon Cancer, Lynch Syndrome)
  • FAP (Familial Adenomatous Polyposis)
  • AFAP (Attenuated Familial Adenomatous Polyposis)
  • APCI 1307K
  • Peutz-Jehger’s Syndrome
  • MAP (MYH Associated Polyposis)
  • Juvenile Polyposis

What type of information regarding family history should I tell my colon and rectal surgeon?

Family history information regarding the ­following items will allow your colon and ­rectal surgeon to formulate the best plan for prevention and treatment.

• All family members and their approximate ages of when they were diagnosed with ­colorectal polyps or cancer

• Family history of gynecologic cancers ­(ovarian or uterine)

What will the colon and rectal surgeon do with this information?

The colon and rectal surgeon will use this information to assess an individual’s risk for CRC. Additional evaluation of an individual may help to detect and identify a family cancer syndrome. Recommendations for this analysis may include colonoscopy, genetic counseling, formal generic testing, regular follow-up examination, and potential referral to other medical specialists.

© 2008 American Society of Colon and Rectal Surgeons