Dr. M.J. Bazos, MD
Patient Handout
COLON
CANCER
About Your
Diagnosis
Colon cancer, colorectal
cancer, and adenocarcinoma of the large intestine (bowel) are the same thing.
Colon cancer is the most common cancer of the gastrointestinal tract. The cancer
commonly involves the lower rectum and sigmoid portion of the colon but also can
be found at the beginning of the colon (the cecum). Approximately 160,000 people
will be found to have colon cancer this year. Although not completely
understood, environmental and hereditary factors are believed to lead to colon
cancer. A high consumption of saturated fat (animal fat) and a lowfiber diet are
leading theories of a dietary cause of colon cancer. The main risk factors for
colorectal cancer are age older than 50 years, long-standing inflammatory bowel
disease (ulcerative colitis, Crohn’s disease), genital or breast cancer,
and a family history of colon cancer or familial polyposis. Colon cancer is
usually detectable by means of colonoscopy (a scope is passed through the rectum
to visualize the entire colon). Biopsies are easily performed on any suspicious
areas, and any polyps (growths from the surface of the colon that can transform
into malignant cancer) can be removed. Colon cancer can be cured if detected
early, before it has had the chance to spread (metastasize). The best way to
detect colon cancer early is by means of screening (see
below).
Living With Your
Diagnosis
Signs and symptoms to be
aware of are change in bowel habits, such as constipation; change in the caliber
of stools (e.g., pencil-thin stools); black tarry stools; frank rectal bleeding;
and abdominal pain. Sometimes you may not have any symptoms but may be found to
have iron deficiency anemia. This usually necessitates evaluation to exclude
colon cancer. Colon cancer if undetected or untreated usually spreads through
the wall of the intestine into the surrounding areas and also into the liver.
Sometimes it can spread to the lungs and
bone.
Treatment
The
best treatment is prevention by means of screening. Screening guidelines include
the following: a digital rectal examination annually after 40 years of age;
testing of stools for occult blood annually after 50 years of age; and flexible
sigmoidoscopy every 3 to 5 years after the age of 50 years. Once the diagnosis
of colon cancer is made, treatment depends on the extent of spread of the
cancer. Abdominal and pelvic computed tomography (CT) is performed to determine
whether the tumor has spread to the liver or outside the colon to regional lymph
nodes. This information is important because it is used to decide whether
chemotherapy is needed. Surgical intervention is the best therapy for complete
removal of the tumor and the best chance for cure if there is no evidence of
spread. Also with surgical treatment, additional information is found about
local extension of the tumor within the layers of the wall of the colon and
within regional lymph nodes. This information is important because chemotherapy
and radiation therapy may be recommended after surgical treatment. Side effects
and complications of surgical treatment include pain and infection. Radiation
therapy may cause colitis with diarrhea and bloody stools. Chemotherapy can lead
to bone marrow suppression making one prone to infection, bleeding, and anemia.
Other side effects of chemotherapy include nausea, vomiting, diarrhea, hair
loss, and mucositis (pain and redness) of the eyes and
mouth.
The
DOs
• Understand the
importance of colon screening for all persons older than 50 years and for all
family members of patients with colon
cancer.
• Make sure your
diet is high in fiber and low in animal
fat.
• Make sure that once
your cancer is diagnosed and you are treated and cured, you undergo colonoscopy
1 year postoperatively and every 3 years
thereafter.
• Understand
that there is a blood test called carcinoembryonic antigen (CEA) measurement
that is usually performed once the diagnosis of colon cancer is made and after
surgical treatment to detect
recurrence.
The
DON’Ts
• Do not
forget the importance of
screening.
• Do not miss
follow-up appointments with your primary care physician, oncologist, radiation
oncologist if radiation therapy was provided, and general surgeon for wound care
and colostomy care if you have a
colostomy.
• Do not be
afraid to ask your primary care physician about emotional support groups.
• Do not forget the
importance of nutrition after surgical
treatment.
When to Call
Your Doctor
• If you
have change in bowel habits, bloody or black stools, diarrhea, or
constipation.
• If you have
new abdominal pain or back pain with lower leg
weakness.
• If you note skin
color change such as
jaundice.
• If you have a
fever during chemotherapy.
•
If you note abnormal drainage from within or around the colostomy
site.
• If you continue to
have no appetite and weight
loss.
• If nausea and
vomiting persist.