WHAT IS LUNG CANCER?
Lung cancer is the leading cancer killer in both
men and women. An estimated 173,700 new cases of
lung cancer and an estimated 160,440 deaths from
lung cancer will occur in the United States
during 2004.
The rate of lung cancer cases appears to be
dropping among white and African-American men in
the United States, while it continues to rise
among both white and African-American women.
There are two major types of lung cancer:
non-small cell lung cancer and small cell lung
cancer. Non-small cell lung cancer is much more
common. It usually spreads to different parts of
the body more slowly than small cell lung
cancer. Squamous cell carcinoma, adenocarcinoma,
and large cell carcinoma are three types of
non-small cell lung cancer. Small cell lung
cancer also called oat cell cancer, accounts for
about 20% of all lung cancer.
WHAT CAUSES LUNG CANCER?
Smoking is the number one cause of lung cancer.
Lung cancer may also be the most tragic cancer
because in most cases, it might have been
prevented -- 87% of lung cancer cases are caused
by smoking. Cigarette smoke contains more than
4,000 different chemicals, many of which are
proven cancer-causing substances, or
carcinogens. Smoking cigars or pipes also
increases the risk of lung cancer.
The more time and quantity you smoke, the
greater your risk of lung cancer. But if you
stop smoking, the risk of lung cancer decreases
each year as normal cells replace abnormal
cells. After ten years, the risk drops to a
level that is one-third to one-half of the risk
for people who continue to smoke. In addition,
quitting smoking greatly reduces the risk of
developing other smoking-related diseases, such
as heart disease, stroke, emphysema and chronic
bronchitis.
Many of the chemicals in tobacco smoke also
affect the
nonsmoker inhaling the
smoke, making "secondhand smoking" another
important cause of lung cancer. It is
responsible for approximately 3,000 lung cancer
deaths annually.
Radon is considered to be the second leading
cause of lung cancer in the U.S. today. Radon
gas can come up through the soil under a home or
building and enter through gaps and cracks in
the foundation or insulation, as well as through
pipes, drains, walls or other openings. Radon
causes between 15,000 and 22,000 lung cancer
deaths each year in the United States -- 12
percent of all lung cancer deaths are linked to
radon.
Radon problems have been found in every state.
The EPA estimates that nearly 1 out of every 15
homes in the U.S. has indoor radon levels at or
above the level at which homeowners should take
action -- 4 picocuries per liter of air (pCi/L)
on a yearly average. Radon can be a problem in
schools and workplaces, too.
Because you cannot see or smell radon, the only
way to tell if you are being exposed to the gas
is by measuring radon levels. Exposure to radon
in combination with cigarette smoking greatly
increases the risk of lung cancer. That means
for smokers, exposure to radon is an even
greater health risk.
Another leading cause of lung cancer is
on-the-job exposure to cancer-causing substances
or carcinogens. Asbestos is a well-known,
work-related substance that can cause lung
cancer, but there are many others, including
uranium, arsenic, and certain petroleum
products.
There are many different jobs that may involve
exposure. Some examples are working with certain
types of insulation, working in coke ovens, and
repairing brakes. When exposure to job-related
carcinogens is combined with smoking, the risk
of getting lung cancer is sharply increased.
A recent study published in the Journal of
American Medical Association suggests that
particulate matter pollution can cause lung
cancer.
Lung cancer takes many years to develop. But
changes in the lung can begin almost as soon as
a person is exposed to cancer-causing
substances. Soon after exposure begins, a few
abnormal cells may appear in the lining of the
bronchi (the main breathing tubes). If a person
continues to be exposed to the cancer-causing
substance, more abnormal cells will appear.
These cells may be on their way to becoming
cancerous and
forming tumor.
HOW IS LUNG CANCER DETECTED
In its early stages, lung cancer usually does
not cause symptoms. When symptoms occur, the
cancer is often advanced. Symptoms of lung
cancer include:
- Chronic cough
- Hoarseness
- Coughing up blood
- Weight loss & loss of appetite
- Shortness of breath
- Fever without a known reason
- Wheezing
- Repeated bouts of bronchitis or pneumonia
- Chest pain
These conditions are also symptomatic of many
other lung problems, so a person who has any of
these symptoms should see a doctor to find out
the cause. When a person goes for an exam, the
doctor ask many questions about the person's
medical history, including questions about the
patient's exposure to hazardous substances. The
doctor will also give the patient a physical
exam. If the patient has a cough that produces a
sputum (mucus), it may be examined for cancer
cells. The doctor will order a chest X-ray or
specialized X-ray such as the CT scan, which
help to locate any abnormal spots in the lungs.
The doctor may insert a small tube called a
bronchoscope through the nose or mouth and down
the throat, to look inside the airways and lungs
and take a sample, or biopsy, of the tumor. This
is just one of several ways in which a doctor
may take a biopsy sample.
A growing number of doctors are using a form of
CT scan in smokers to spot small lung cancers,
which are more likely than large tumors to be
cured. The technique, called helical low-dose CT
scan, is much more sensitive than a regular
X-ray and can detect tumors when they are small.
More studies on this type of screening will show
whether routine screening of smokers and others
at risk for lung cancer will save lives.
If you are diagnosed with cancer, the doctor
will do testing to find out whether the cancer
has spread, and, if so, to which parts of the
body. This information will help the doctor plan
the most effective treatment. Tests to find out
whether the cancer has spread can
The doctor will decide which treatment you will
receive based on factors such as the type of
lung cancer, the size, location and extent of
the tumor (whether or not it has spread), and
your general health. There are many treatments,
which may be used alone or in combination. These
include:a
CT scan,an MRI,or a bone scan.
HOW IS LUNG CANCER TREATED?
1-SURGERY:
may cure lung cancer. It is used in limited
stages of the disease. The type of surgery
depends on where the tumor is located in the
lung. Some tumors cannot be removed because of
their size or location.
2-RADIATION THERAPY
Is a form of high energy X-ray that kills cancer
cells.
It is used In combination with chemotherapy and
sometimes with surgery to offer relief from pain
or blockage of the airways.
3-CHEMOTHERAPY
Is the use of drugs that are effective against
cancer cells. Chemotherapy may be injected
directly into a vein or given through a
catheter, which is a thin tube that is placed
into a large vein and kept there until it is no
longer needed. Some chemotherapy drugs are taken
by pill. Chemotherapy may be used:
- In conjunction with surgery.
- In more advanced stages of the disease to
relieve symptoms.
- In all stages of small cell cancer.
Some patients may also be eligible to
participate in clinical trials or research
studies that look at new ways to treat lung
cancer.
HOW CAN YOU PREVENT LUNG CANCER?
- If you are a smoker,
STOP SMOKING. Your
local American Lung Association has books,
videos, and group programs to help you quit for
good.
- The Lung Association is also offering a new
way to stop smoking through its Freedom
From Smoking® online
smoking cessation clinic.
- If you are a nonsmoker, know your rights to a
smoke-free environment a twork and in public
places. Make your home smoke-free.
- Test your home for radon.
- If you are exposed to dusts and fumes at work,
ask questions about how you are being protected.
Don't smoke -- smoking increases your risk from
many occupational exposures.