- The Esophagus
- Understanding the Cancer Process
- Risk Factors
- Recognizing Symptoms
- Diagnosing Esophageal Cancer
- Staging the Disease
- Orthodox Treatment
- Side Effects of Orthodox Treatment
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.
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