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 Introduction
 Your lungs are part of the respiratory system which enables you to
breathe. Lungs looks like Pinkish-gray, spongy tissue. Your right lung
is a little larger than your left and has three section, or lobes. Your
left lung has two lobes, and your heart takes up some of the room on the
left side of your chest The air you inhale from your mouth or nose goes
through breathing tubes, or passages, and branches into the main air
passages of the lung called bronchi. One bronchus goes to the right and
one to the left lung. Your bronchi branch into smaller and smaller tubes
that carry air to all parts of your lung. They end in clusters of tiny
air sacs called alveoli. Each lung contains millions of alveoli.
Lung cancer, like other cancers, is an
expression of the uncontrolled growth of abnormal cells. Most lung
cancers begin on the bronchi (the larger air tubes) or the brounchioles
(the smaller tubes branching off the bronchi).
Normally cells grow in an orderly,
controlled pattern. As normal cells wear out, new ones are produced.
Just enough new cells grow to replace the old ones.
Cell of each part of your body such as
your bones, skin and heart differ in shape and function. Each type of
cell is designed to do a particular job in a particular organ.
When cell division is not orderly,
abnormal growth takes place. Masses of tissue called tumors build up.
Tumors may be benign or malignant.
Benign tumors remain localized and
usually do not spread or threaten one's life. They can be removed
completely by surgery and are not likely to recur.
Malignant tumors are cancers. They can
invade and destroy nearby tissues and organs or spread to other parts of
the body. The new growths they form in other parts of the body are
called metastases. Even if cancer is removed by surgery or radiation
therapy, it may sometimes recur because cancer cells have spread before
having begun treatment of the local disease.
Symptoms
A cough, the most common symptom of lung cancer, is likely to occur when
a growing cancer blocks an airway. You cough as if you were trying to
get rid of a foreign object stuck in your lungs. In some cases your
saliva is streaked with rusty or even bright red blood.
Another symptom is a chest pain. It
occurs as a persistent ache that might or might not be related to
coughing.
You may develop a wheeze, or
hoarseness, or find yourself short of breath. Repeat bouts of pneumonia
or bronchitis, too may be an indication of lung cancer. And like all
cancers, lung cancer can cause fatigue, loss of appetite, and weight
loss.
In addition, there may be symptoms that
seem entirely unrelated to the lungs. These may be caused by spread of a
lung cancer to other parts of the body,
When you see your doctor, you should
report all aches or pains. They may be important clues.
Diagnosis
Diagnosis begins with a physical examination by your doctor. There are a
number of tests he may use to confirm a suspected diagnosis of lung
cancer and to determine the type of the disease.
Chest X-rays are important in detecting
lung cancer. In additions to the conventional chest X-ray, a number of
other X-ray procedures are available to assist the diagnosis, such as
tomograms, bronchograms, and angiograms.
Lung tomograms are special chest
X-rays, perfected some years ago. A tomogram is a. series of pictures of
various sections of lung tissue. When these pictures are put together,
they give a three-dimensional picture of any abnormal lung growth. If
the tomograms suggest that a lump is cancerous, additional studies are
needed to narrow down the diagnosis. More recently, a newly developed
type of tomograrn, called a "CAT" scan (computerized axial
tomography) has on occasion proven to be helpful.
Bronchograms outline the inside of lung
passages and may show tumors that are otherwise invisible.
Angiograms, X-ray studies of blood
vessels made visible with an injected dye, can reveal a displacement of
a vein or artery by a tumor.
Your doctor recognizes distinctive
characteristics of cancer that determine whether microscopic examination
of a specimen of tissue from the suspected area should be made. The
surgical removal of small amount of tissue and its examination under a
microscope is known as a biopsy. The examination of the bit of tissue
removed is made by a pathologist, a physician who interprets and
diagnoses changes caused by disease in the body tissues.
Several other diagnostic methods are
being performed at many hospitals. Lung cancer cells found in the sputum
(mucus and pus from the bronchial tubes) will indicate to doctors the
nature of a lesion seen on X-ray but not clearly defined as cancer. This
method is an adaptation of the Pap test (mucus and a bit of tissue
scraped from the cervix for examination under a microscope) which has
proved to be of much value in early diagnosis of uterine cervical
cancer.
A new instrument called the fiber-optic
bronchoscope also is being used to help in locating and biopsying
suspicious areas. The bronchoscope is a thin, flexible tube which is
threaded into the larger branches of lung airways. By means of a viewer
that resembles a tiny television screen, your physician can check all
sections of your lung. This instrument helps to identify most (if not
all) sites that may be cancerous.
Mediastinoscopy and mediastonotomy are
sometimes used to determine whether suspected disease is cancer and has
spread to the central areas of the chest (mediastinum). In the former
procedure a viewing instrument is introduced into this area while in the
latter procedure a surgical exploration is performed. These are
relatively simple procedures.
When simpler diagnostic techniques have
not conclusively revealed the nature of a suspicious area in the lung,
your physician may prescribe an exploratory chest operation called a
thoracotomy.
Types of Lung Cancer
Cell types are the basis for classification of lung cancers. The most
prevalent kinds are epidermoid, carcinoma large cell carcinoma, small,
cell carcinoma, and adenocarcinoma
Epidermoid or squamous cell carcinoma
of the lung arises from cells that line the airways. It is the most
common type of lung cancer, accounting for about 35 percent of all
cases.
Large cell carcinoma of the lung is
characterized by large, rounded cells. This type accounts for about 28
percent of all lung cancers.
Small cell carcinoma of the lung, also
called oat cell carcinoma because of the cell shape, accounts for about
14 percent of all lung cancer. It is generally found in persons who are
heavy cigarette smokers .
Adenocarcinoma of the lung originates
and frequently grows directly under the mucous membrane (the inner
lining of the air passages of the lung). It accounts for about 20
percent of all lung cancers.
The remaining 3 percent include other
types of lung cancer.
When a diagnosis of lung cancer is
confirmed by your doctor, it is best to begin treatment in a hospital
that has an expert staff and the resources available to apply all forms
of effective therapy right from the beginning. You may wish to request a
second opinion from another physician to confirm the first diagnosis and
recommendations for therapy.
Treatment
Your medical history, your general health, the type and location of the
cancer or cancers, and many other factors are considered in determining
the treatment needed. Your treatment must be tailored to your individual
needs.
Treatment of lung cancer may take
several forms - surgery, radiation therapy, and chemotherapy often in
combination, depending on your needs.
Surgery is the most common treatment
for cancers that are small, slow growing, and have neither invaded
nearby tissue nor metastasized (spread). Your surgeon must determine how
much of your lung to remove, and if it is necessary to include nearby
lymph nodes (bean shaped structures in the lymphatic system)
In recent years, advances in surgical
techniques and medical care have made extensive surgery possible for
persons previously considered too old or infirm for this treatment.
Today surgeons have the help of highly competent teams of nurses,
therapists, technicians and other professionals to support patients
throughout their post-operative period.
Following such an operation you should
have regular medical checkups to watch for recurrence metastasis, or a
second tumor elsewhere in your lung. If you were a smoker, you must stop
smoking.
Treatment by radiation therapy may be
used in combination with surgery. It is given either before or after
your operation. Radiation therapy may be administered in a number of
ways.
The basic principle of radiation
therapy is to focus the beam of radiation on the cancer at doses that
will destroy the cancer with minimal damage to surrounding normal
tissue. Radiation therapy uses X-rays, cobalt or other sources of
ionizing radiation for destruction of the cancer.
If you have widely spread lung cancer
treatment with anticancer drugs is chosen. Radiation therapy is kept in
reserve as a palliative measure. Such palliative radiation therapy can
greatly improve your quality of life by relieving distressing symptoms,
such as severe cough, pain, shortness of breath, or difficulty in
swallowing.
Chemotherapy (treatment with anticancer
drugs) is available to your physician in treating lung cancer.
Anticancer drugs kill cancer cells because the drugs can act on normal
cells as well as cancerous ones, your physician must maintain a delicate
balance of enough drugs to kill cancer cells without destroying too many
healthy cells.
Some anticancer drugs may make you feel
sick temporarily, but your doctor tries to work out a treatment schedule
that disrupts your daily routine as little as possible. The length and
frequency of chemotherapy depend upon a number of factors. These include
your type of cancer, the type of anticancer drugs prescribed, how long
it takes you to respond to these drugs, and how well you tolerate side
effects of the drugs. Most chemotherapy programs are carried out in the
outpatients department of a hospital. However sometimes short periods of
hospitalization may be necessary in order to monitor the drug very
closely.
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Patient Education
