- Types of Lung Cancer
- Orthodox Treatment
- How non-small cell lung cancer
- How small cell lung cancer is
The lungs, two sponge-like organs in your chest, work along
with your ribs and chest muscles to bring air in and out of
your body. Air is drawn in through your nose or mouth, down
through your trachea, or windpipe, and then into your bronchi,
the tubes that go into each lung. In your lungs, the bronchi
divide further into bronchioles, which end in tiny balloon-like
sacs called alveoli. These sacs are found throughout your
lungs and are the places where oxygen from the air is exchanged
for the waste product carbon dioxide, which you exhale.
Each lung is composed of sections called lobes. Your right
lung has three lobes, while the left has two, leaving more
room on that side for the heart. Lung cancer can begin in
the alveoli, bronchioles, or trachea, but it most often starts
in the bronchi.
Lung cancer is difficult to detect early because symptoms
usually do not appear until the disease is advanced. Symptoms
depend on the location of the tumor and can include persistent
cough, hoarseness or wheezing, shortness of breath, sputum
streaked with blood, recurring bronchitis or pneumonia, weight
loss and loss of appetite, and chest pain.
Physicians use several techniques to diagnose lung cancer.
Chest x-rays and CT (computed tomography) scans help locate
abnormal areas in the lung. A new technique called spiral
CT may offer a novel approach for screening for the disease.
A sputum sample can also be analyzed for the presence of cancerous
cells. Doctors may perform a bronchoscopy, which allows them
to examine the bronchial passages using an instrument called
a bronchoscope. This is a small tube that is inserted through
the nose or mouth, down the throat and into the bronchi. During
the procedure physicians may remove some tissue for analysis.
To examine areas of the lungs that are not accessible during
a bronchoscopy, physicians may perform a needle biopsy to
remove a small sample of tissue for analysis.
Types of Lung Cancer
There are two major types of lung cancer: small cell and
non-small cell. They each affect different types of cells
in the lung and grow and spread in a different ways, so doctors
treat them differently. A diagnosis will include not only
the type of lung cancer but the stage, which describes the
extent and spread of the disease at diagnosis.
Non-small-cell lung cancer, the most common type of lung
cancer, is usually associated with a history of smoking, passive
smoking, or exposure to radon. It can be further divided into
three categories named for the type of cell found in the tumor:
squamous cell carcinoma (also called epidermoid carcinoma),
adenocarcinoma, and large cell carcinoma. Non-small-cell lung
cancer is described using four stages. In stage one the cancer
is confined to the lung; in stages two and three the cancer
is confined to the chest; and in stage four the cancer has
spread from the chest.
Small-cell lung cancer, also called oat cell lung cancer,
accounts for a quarter of all lung-cancer cases and is associated
with a history of smoking. The extent of the disease is described
using a two-stage system. A case can be limited, meaning the
cancer is confined to a portion of the chest, or extensive,
meaning the cancer has spread throughout or from the chest.
Tumors found in the lungs sometimes originate in cancer elsewhere
in the body. In these cases, treatment will be different from
that for cancer that originates in the lungs.
Lung cancer can be treated with surgery, chemotherapy, radiation,
or a combination of these modalities, depending on the type
and stage of the disease. For non-small-cell lung cancers
that have not spread beyond the lung, surgery is most often
used. Over the past several years, surgical techniques for
treating lung cancer have improved greatly. When the disease
has spread, treatment will often include radiation therapy
and chemotherapy. For small-cell lung cancer, chemotherapy,
often combined with radiation therapy, is now the most common
treatment. Radiation therapy is also sometimes used in both
forms of lung cancer to relieve pain and bleeding and alleviate
problems with swallowing.
How non-small cell lung cancer is treated
Chemotherapy uses drugs to kill cancer cells. Chemotherapy
may be taken by pill, or it may be put into the body by a
needle in the vein or muscle. Chemotherapy is called a systemic
treatment because the drug enters the bloodstream, travels
through the body, and can kill cancer cells outside the lungs.
Chemoprevention uses drugs to prevent a second cancer from
Radiation therapy uses high-energy x-rays to kill cancer
cells and shrink tumors. Radiation may come from a machine
outside the body (external radiation therapy) or from putting
materials that produce radiation (radioisotopes) through thin
plastic tubes in the area where the cancer cells are found
(internal radiation therapy).
One new type of radiation therapy is called radiosurgery.
In radiosurgery, radiation is directly focused on the tumor,
and involves as little normal tissue as possible. Radiosurgery
is usually used as treatment of tumors that involve the brain.
Cryosurgery freezes the tumor and kills it. Photodynamic
therapy uses a certain type of light and a special chemical
to kill cancer cells. Laser therapy uses a narrow beam of
light to kill cancer cells. Cryosurgery and photodynamic therapy
are usually used in clinical trials.
Surgery, radiation therapy, and chemotherapy are used to
treat non-small cell lung cancer. However, these treatments
often do not cure the disease.
If lung cancer is found, a patient may want to think about
taking part in one of the many clinical trials being done
to improve treatment. Clinical trials are ongoing in most
parts of the country for all stages of non-small cell lung
cancer. Treatment choices can be discussed with a doctor.
Patients with non-small cell lung cancer can be divided into
three groups, depending on the stage of the cancer and the
treatment that is planned. The first group (stages 0, I, and
II) includes patients whose cancers can be taken out by surgery.
The operation that takes out only a small part of the lung
is called a wedge resection. When a whole section (lobe) of
the lung is taken out, the operation is called a lobectomy.
When one whole lung is taken out, it is called a pneumonectomy.
Radiation therapy may be used to treat patients in this group
who cannot have surgery because they have other medical problems.
Like surgery, radiation therapy is called local treatment
because it works only on the cells in the area being treated.
The second group of patients has lung cancer that has spread
to nearby tissue or to lymph nodes. These patients can be
treated with radiation therapy alone or with surgery and radiation,
chemotherapy and radiation, or chemotherapy alone.
The third group of patients has lung cancer that has spread
to other parts of the body. Radiation therapy may be used
to shrink the cancer and to relieve pain. Chemotherapy may
be used to treat some patients in this group.
How small cell lung cancer is treated
There are treatments for all patients with small cell lung
cancer. Three kinds of treatment are used: surgery, radiation
therapy and chemotherapy.
Additionally, clinical trials are testing the effect of new
therapies on the treatment of small cell lung cancer.
Surgery may be used if the cancer is found only in one lung
and in nearby lymph nodes. Because this type of lung cancer
is usually not found in only one lung, surgery alone is not
often used. Occasionally, surgery may be used to help determine
exactly which type of lung cancer the patient has. If a patient
does have surgery, the doctor may take out the cancer in one
of the following operations:
- Wedge resection removes only a small part of the lung.
- Lobectomy removes an entire section (lobe) of the lung.
- Pneumonectomy removes the entire lung.
During surgery, the doctor will also take out lymph nodes
to see if they contain cancer.
Radiation therapy uses x-rays or other high-energy rays to
kill cancer cells and shrink tumors. Radiation therapy for
small cell lung cancer usually comes from a machine outside
the body (external beam radiation therapy). It may be used
to kill cancer cells in the lungs or in other parts of the
body where the cancer has spread. Radiation therapy may also
be used to prevent the cancer from growing in the brain. This
is called prophylactic cranial irradiation (PCI). Because
PCI may affect brain function, the doctor will help the patient
decide whether to have this kind of radiation therapy. Radiation
therapy can be used alone or in addition to surgery and/or
Chemotherapy is the most common treatment of all stages of
small cell lung cancer. Chemotherapy may be taken by pill,
or it may be put into the body by a needle in the vein or
muscle. Chemotherapy is called a systemic treatment because
the drug enters the bloodstream, travels through the body,
and can kill cancer cells outside the lungs, including cancer
cells that have spread to the brain.