Cancer
of esophagus (also called esophageal cancer) is divided
into two major types, squamous cell carcinoma and
sadenocarcinoma,
depending on the type of cells that are malignant.
Squamous cell carcinomas arise in squamous cell that
line the esophagus. These cancers usually occur in
the upper and middle part of the esophagus. Adenocarcinomas
usually develop in the glandular tissue in the lower
part of the esophagus. The treatment is similar for
both types of esophageal cancer.
Conventional
esophageal cancer treatment can be generally categorized
in four kinds, surgery, radiation, chemotherapy &
immune therapy. The previous two are non-systematic.
They have no effect on cancer cells that spread to
other organs. The posterior two are systematic. But
they can rarely reach the center of the tumor where
always lack of blood. Therefore, doctors usually adopt
a complex treatment which includes at least two of
the above.
The Esophagus
The
esophagus is a hollow tube that carries food and liquids
from the
throat to the stomach. When a person swallows, the
muscular walls of
the esophagus contract to push food down into the
stomach. Glands in the lining of the esophagus produce
mucus, which keeps the passageway moist and makes
swallowing easier. The esophagus is located just behind
the trachea (windpipe). In an adult, the esophagus
is about 10 inches long.
Understanding
the Cancer Process
Cancer
is a disease that affects cells, the body's basic
unit of life. To
understand any type of cancer, it is helpful to know
about normal cells and what happens when they become
cancerous.
The body is made up of many types of cells. Normally,
cells grow, divide, and produce more cells when they
are needed. This process keeps the body healthy and
functioning properly. Sometimes, however, cells keep
dividing when new cells are not needed. The mass of
extra cells forms a growth or tumor. Tumors can be
benign or malignant.
Benign
tumors are not cancer. They usually can be removed
and, in most cases, they do not come back. Cells in
benign tumors do not spread to other parts of the
body. Most important, benign tumors are rarely a threat
to life.
Malignant
tumors are cancer. Cells in malignant tumors are abnormal
and divide without control or order. These cancer
cells can invade and
destroy the tissue around them. Cancer cells can also
break away from a malignant tumor and enter the bloodstream
or lymphatic system (the tissues and organs that produce,
store, and carry white blood cells that fight infection
and other diseases). This process, called metastasis,
is how cancer spreads from the original (primary)
tumor to form new (secondary) tumors in other parts
of the body.
Cancer that begins in the esophagus (also called esophageal
cancer) is divided into two major types, squamous
cell carcinoma and adenocarcinoma, depending on the
type of cells that are malignant. Squamous cell carcinomas
arise in squamous cells that line the esophagus. These
cancers usually occur in the upper and middle part
of the esophagus. Adenocarcinomas usually develop
in the glandular tissue in the lower part of the esophagus.
The treatment is similar for both types of esophageal
cancer.
If the cancer spreads outside the esophagus, it often
goes to the lymph nodes first. (Lymph nodes are small,
bean-shaped structures that are part of the body's
immune system.) Esophageal cancer can also spread
to almost any other part of the body, including the
liver, lungs, brain, and bones.
Risk
Factors
The
exact causes of cancer of the esophagus are not known.
However, studies show that any of the following factors
can increase the risk of developing esophageal cancer:
Age.
Esophageal cancer is more likely to occur as people
get older; most people who develop esophageal cancer
are over age 60.
Sex.
Cancer of the esophagus is more common in men than
in women.
Tobacco
Use. Smoking cigarettes or using smokeless tobacco
is one of the major risk factors for esophageal cancer.
Alcohol
Use. Chronic and/or heavy use of alcohol is another
major risk
factor for esophageal cancer. People who use both
alcohol and tobacco have an especially high risk of
esophageal cancer. Scientists believe that these substances
increase each other's harmful effects.
Barrett's
Esophagus. Long-term irritation can increase the risk
of esophageal cancer. Tissues at the bottom of the
esophagus can become irritated if stomach acid frequently
"backs up" into the esophagus's problem
called gastric reflux. Over time, cells in the irritated
part of the esophagus may change and begin to resemble
the cells that line the stomach. This condition, known
as Barrett's esophagus, is a premalignant condition
that may develop into adenocarcinoma of the esophagus.
Other
Types of Irritation. Other causes of significant irritation
or damage to the lining of the esophagus, such as
swallowing lye or other caustic substances, can increase
the risk of developing esophageal cancer.
Medical
History. Patients who have had other head and neck
cancers have an increased chance of developing a second
cancer in the head and neck area, including esophageal
cancer.
Having any of these risk factors increases the likelihood
that a person
will develop esophageal cancer. Still, most people
with one or even several of these factors do not get
the disease. And most people who do get esophageal
cancer have none of the known risk factors.
Identifying factors that increase a person's chances
of developing esophageal cancer is the first step
toward preventing the disease. We
already know that the best ways to prevent this type
of cancer are to quit (or never start) smoking cigarettes
or using smokeless tobacco and to drink alcohol only
in moderation. Researchers continue to study the causes
of esophageal cancer and to search for other ways
to prevent it. For example, they are exploring the
possibility that increasing one intake of fruits and
vegetables, especially raw ones, may reduce the risk
of this disease.
Researchers are also studying ways to reduce the risk
of esophageal cancer for people with Barrett's esophagus.
Recognizing Symptoms
Early
esophageal cancer usually does not cause symptoms.
However, as the cancer grows, symptoms may include:
Difficult
or painful swallowing
Severe
weight loss
Pain
in the throat or back, behind the breastbone or between
the shoulder blades
Hoarseness
or chronic cough
Vomiting
Coughing
up blood
These symptoms may be caused by esophageal cancer
or by other conditions.
It is important to check with a doctor.
Diagnosing
Esophageal Cancer
To
help find the cause of symptoms, the doctor evaluates
a person's medical history and performs a physical
exam. The doctor usually orders a chest x-ray and
other diagnostic tests. These tests may include the
following:
A
barium swallow (also called an esophagram) is a series
of x-rays of the esophagus. The patient drinks a liquid
containing barium, which coats the inside of the esophagus.
The barium makes any changes in the shape of the esophagus
show up on the x-rays.
Esophagoscopy
(also called endoscopy) is an examination of the inside
of the esophagus using a thin lighted tube called
an endoscope. An anesthetic (substance that causes
loss of feeling or awareness) is usually used during
this procedure. If an abnormal area is found, the
doctor can collect cells and tissue through the endoscope
for examination under a microscope. This is called
a biopsy. A biopsy can show cancer, tissue changes
that may lead to cancer, or other conditions.
Staging
the Disease
If
the diagnosis is esophageal cancer, the doctor needs
to learn the stage (or extent) of disease. Staging
is a careful attempt to find out whether the cancer
has spread and, if so, to what parts of the body.
Knowing the stage of the disease helps the doctor
plan treatment. Listed below are descriptions of the
four stages of esophageal cancer.
Stage
I. The cancer is found only in the top layers
of cells lining the
esophagus.
Stage
II. The cancer involves deeper layers of
the lining of the esophagus, or it has spread to nearby
lymph nodes. The cancer has not spread to other parts
of the body.
Stage
III. The cancer has invaded more deeply into
the wall of the esophagus or has spread to tissues
or lymph nodes near the esophagus. It has not spread
to other parts of the body.
Stage
IV. The cancer has spread to other parts
of the body. Esophageal cancer can spread almost anywhere
in the body, including the liver, lungs, brain, and
bones.
Some tests used to determine whether the cancer has
spread include:
CAT
(or CT) scan (computed tomography). A computer linked
to an x -ray machine creates a series of detailed
pictures of areas inside the body.
Bone
scan. This technique, which creates images of bones
on a computer screen or on film, can show whether
cancer has spread to the bones. A small amount of
radioactive substance is injected into a vein; it
travels through the bloodstream, and collects in the
bones, especially in areas of abnormal bone growth.
An instrument called a scanner measures the radioactivity
levels in these areas.
Bronchoscopy.
The doctor puts a bronchoscope (a thin, lighted tube)
into the mouth or nose and down through the windpipe
to look into the breathing passages.
Orthodox Treatment
Treatment
for esophageal cancer depends on a number of factors,
including the size, location, and extent of the tumor,
and the general health of the patient. Patients are
often treated by a team of specialists, which may
include a gastroenterologist (a doctor who specializes
in diagnosing and treating disorders of the digestive
system), surgeon (a doctor who specializes in removing
or repairing parts of the body), medical oncologist
(a doctor who specializes in treating cancer), and
radiation oncologist (a doctor who specializes in
using radiation to treat cancer). Because cancer treatment
may make the mouth sensitive and at risk for infection,
doctors often advise patients with esophageal cancer
to see a dentist for a dental exam and treatment before
cancer treatment begins.
Many different treatments and combinations of treatments
may be used to control the cancer and/or to improve
the patient's quality of life by reducing symptoms.
Surgery is the most common treatment for esophageal
cancer. Usually, the surgeon removes the tumor along
with all or a portion of the esophagus, nearby lymph
nodes, and other tissue in the area. (An operation
to remove the esophagus is called an esophagectomy.)
The surgeon connects the remaining healthy part of
the esophagus to the stomach so the patient is still
able to swallow. Sometimes, a plastic tube or part
of the intestine is used to make the connection. The
surgeon may also widen the opening between the stomach
and the small intestine to allow stomach contents
to pass more easily into the small intestine. Sometimes
surgery is done after other treatment is finished.
Radiation
therapy, also called radiotherapy, involves the use
of high-energy rays to kill cancer cells. Radiation
therapy affects cancer cells in the treated area only.
The radiation may come from a machine outside the
body (external radiation) or from radioactive materials
placed in or near the tumor (internal radiation).
A plastic tube may be
inserted into the esophagus to keep it open during
radiation therapy. This procedure is called intraluminal
intubation and dilation. Radiation therapy may be
used alone or combined with chemotherapy as primary
treatment instead of surgery, especially if the size
or location of the tumor would make an operation difficult.
Doctors may also combine radiation therapy with chemotherapy
to shrink the tumor before surgery. Even if the tumor
cannot be removed by surgery or destroyed entirely
by radiation therapy, radiation therapy can often
help relieve pain and make swallowing easier.
Chemotherapy
is the use of anticancer drugs to kill cancer cells.
The anticancer drugs used to treat esophageal cancer
travel throughout the body. Anticancer drugs used
to treat esophageal cancer are usually given by injection
into a vein (IV). Chemotherapy may be combined with
radiation therapy as primary treatment (instead of
surgery) or to shrink the tumor before surgery.
Laser
therapy is the use of high-intensity light to destroy
tumor cells.
Laser therapy affects the cells only in the treated
area. The doctor may use laser therapy to destroy
cancerous tissue and relieve a blockage in the esophagus
when the cancer cannot be removed by surgery. The
relief of a blockage can help to reduce symptoms,
especially swallowing problems.
Photodynamic
therapy (PDT), a type of laser therapy, involves the
use of drugs that are absorbed by cancer cells; when
exposed to a special light, the drugs become active
and destroy the cancer cells. The doctor may use PDT
to relieve symptoms of esophageal cancer such as difficulty
swallowing.
Side
Effects of Orthodox Treatment
The
side effects of cancer treatment depend on the type
of treatment and may be different for each person.
Doctors and nurses can explain the possible side effects
of treatment, and they can suggest ways to help relieve
symptoms that may occur during and after treatment.
Surgery for esophageal cancer may cause short-term
pain and tenderness in the area of the operation,
but this discomfort or pain can be controlled with
medicine. Patients are taught special breathing and
coughing exercises to keep their lungs clear.
Radiation
therapy affects normal as well as cancerous cells.
Side effects of radiation therapy depend mainly on
the dose and the part of the body that is treated.
Common side effects of radiation therapy to the esophagus
are a dry, sore mouth and throat; difficulty swallowing;
swelling of the mouth and gums; dental cavities; fatigue;
skin changes at the site of treatment; and loss of
appetite.
Chemotherapy,
like radiation therapy, affects normal as well as
cancerous cells. Side effects depend largely on the
specific drugs and the dose (amount of drug administered).
Common side effects of chemotherapy include nausea
and vomiting, poor appetite, hair loss, skin rash
and itching, mouth and lip sores, diarrhea, and fatigue.
These side effects generally go away gradually during
the recovery periods between treatments or after treatment
is over.
Laser
therapy can cause short-term pain where the treatment
was given, but this discomfort can be controlled with
medicine.
Photodynamic
therapy makes the skin and eyes highly sensitive to
light for 6 weeks or more after treatment. Other temporary
side effects of PDT may include coughing, trouble
swallowing, abdominal pain, and painful breathing
or shortness of breath.
