Sam Donaldson's cancer survival tips - National Library of Medicine ...

Colorectal Cancer
Cancer of the colon (large intestine) or rectum (end of the
colon) is called colorectal cancer. In the United States, it is the
third most common cancer in men and women. Caught early, it is
often curable. It is more common in people over 50, and the risk
increases with age. Deaths from colon cancer have fallen nearly
9 percent in the past decade. Better and earlier screening gets
much of the credit, along with better treatments, but the cause
of the disease is still unknown.
Screening and Diagnosis
You are more likely to get colorectal cancer if you have polyps,
growths inside the colon and rectum that may become cancerous.
A family history of colon or rectal cancer puts you at higher risk,
as does ulcerative colitis or Crohn’s disease (also known as inflammatory
bowel disease). Symptoms can include blood in the stool,
narrow stools, a change in bowel habits, and general stomach
discomfort. However, you may not have symptoms at first, so
screening is important. Everyone who is 50 or older should be
screened for colorectal cancer. The most thorough examination
of the colon is done with a colonoscope, which is inserted into the
rectum. A colonoscope is a thin, tube-like instrument, with a light
and a lens for viewing. It may also have a tool to remove tissue
(polyps) to be checked under a microscope for signs of disease.
Treatment
Standard treatments include surgery, chemotherapy, radiation
therapy, or a combination of these methods. Treatment depends
partly on the stage of the cancer. At the
earliest stage (stage 0), doctors may treat
colon cancer with localized surgery, possibly
by removing the cancer cells during
a colonoscopy. For stages I, II, and III
cancer, more extensive surgery is needed.
With advanced colorectal cancer, your
doctor will most likely prescribe chemotherapy.
While radiation therapy is
occasionally used in patients with colon
cancer, it is usually used in combination
with chemotherapy for patients with
advanced rectal cancer.
Research: What’s New
• Combination chemotherapy: Until recently, standard chemotherapy
for colorectal cancer usually consisted of treatment with
just two drugs, 5-fluorouracil (5-FU) and leucovorin. A third
drug, irinotecan, was approved by the FDA in 1996 for use in
combination with 5-FU and leucovorin in treating metastatic
colorectal cancer (cancer that has spread to other parts of the
body). Since then, the drug oxaliplatin has also been approved for
use in combination with 5-FU and leucovorin to treat metastatic
colorectal cancer and post-surgical treatment of this cancer. Unfortunately,
traditional chemotherapy agents often affect healthy
cells, in addition to cancer cells, leading to a variety of side effects.
• Monoclonal antibodies: Targeted monoclonal antibody therapies
— bevacizumab (Avastin) and cetuximab (Erbitux) — have
been available since 2004. One advantage of these targeted therapies
is that they usually have fewer side effects than chemo drugs.
Bevacizumab targets a protein that tumors use to help them grow
new blood vessels. The blood vessels let the tumors get the oxygen
and nutrients they need to keep growing. Cetuximab targets a
protein found on the surface of tumor cells that helps promote
cell growth and multiplication. Both antibodies are approved
only for people with cancer that has metastasized, and they
haven’t yet been shown to work in earlier stages of the disease. In
addition, bevacizumab may increase the risk of heart attacks and
strokes, making it unsafe for certain people.
White House Press Secretary Tony Snow
has returned to work following surgery
for a recurrence of colon cancer.
AP Photo/Ron Edmonds
www.medlineplus.gov Spring 2007 11