By: Peter Noone and Jaquella Howard
Topics in Medicine and Biology
Summer Ventures 2006
If cells grow uncontrollably anywhere in the body, this is called a tumor. If this
tumor is in the lungs, it is called lung cancer. Lung cancer has many causes, the main one
being smoking. It also has many symptoms that make it easier to diagnose. Some of these
symptoms could be many things besides lung cancer, such as a shortness of breath or loss
of appetite. Someone may not even think of lung cancer as a possibility when
experiencing these symptoms. The most common form of diagnosis is a chest x-ray,
which will show the contents of the lungs, and show the doctor if there is a tumor.
Sometimes the tumors can be very hard to detect, however, because it could be in early
stages of development. There are also numerous forms of treatments. The most common
treatments are chemotherapy, and radiotherapy, but there are others that could be used for
specific forms of the cancer.
What is it?
Lung cancer is the presence of a malignant tumor in the lungs. A tumor is the
uncontrolled growth of mutated cells in a specific part of the body, in this case, in the
lungs. A malignant tumor is a tumor that has the ability to spread to other parts of the
body, therefore making it very dangerous and deadly. There can sometimes be a tumor
present in both the right and left lung, and other times there will be a tumor in only one of
the lungs. Most often it is a bronchogenic carcinoma (90% of the time). Lung cancer
causes about 3 million deaths worldwide every year, making it the most deadly cancer. It
used to occur more in men, however occurrence and death in men is beginning to
decrease, and it is continually increasing in women. A woman that smokes is one and a
half times more likely to develop lung cancer than a man with the same smoking habits.
Lung cancer is also more common in African American men and women than in white
men and women.
There are two main types of lung cancer, non-small cell lung cancer, and small cell
lung cancer. Non-small cell cancer is much more common, and spreads much more
slowly than small cell cancer. There are three types of non-small cell cancer, which
account for over 80% of all cases of lung cancer. The three types of non-small cell lung
cancer are Squamous Cell Carcinoma, which begins to grow in the lining of the respiratory
tract, which is mad up of thin, flat cells; Adenocarcinoma, which originates in the lining of the
lung itself; and Large cell carcinoma, which forms tumors that look abnormally large when
observed through a microscope.
Here is a picture of a normal lung next to a cancerous lung. There is quite an obvious
difference. The normal lung is a brown color, while the cancerous one is black and red. This
illustrates how much of a negative affect the tumor had on the lungs. It is easy to see how the
cancer can cause difficulty breathing, due to the distorted shape of the lung, as well as the
obstruction that is the tumor. One can also see the extra red color, which causes the coughing
The average 5-year survival rate for lung cancer is 15 percent, while other cancers,
such as prostate cancer, have much higher rates (the 5-year survival rate for prostate cancer
is 99 percent). If the cancer is diagnosed while it is localized (the tumor has not yet spread to
distant parts of the body) the 5-year survival rate is much better, at 49 percent. However,
only 16 percent of the cases are diagnosed this early. If the cancer is detected after it is
spread, the 5-year survival rate is a mere 2 percent.
The main cause of lung cancer, by far, is smoking. Roughly 87 percent of the cases of
lung cancer in the United States are due to the effects of smoking. Smoking accounts for
about one third of all cancers, not limited to lung cancer, though lung cancer is the cancer that
is linked most closely to smoking. Cigarettes have over 4000 chemicals, many of which have
been identified as cancer-causing. These chemicals can irritate cells in the lungs, and
eventually turn them into cancer cells, which then reproduce uncontrollably, and form a
tumor. Cigarettes isn’t the only tobacco product that causes cancer, in fact, any tobacco
product is hazardous to your health. This is because all of them contain the same carcinogenic
substances that cigarettes do.
The main chemicals that cause lung cancer in tobacco are the following:
• Carbon monoxide
• Nitrogen oxide
The risk of getting lung cancer is directly related with your smoking habits.
The risk increases with the following factors:
• How many cigarettes a day you smoke.
• How deeply you inhale
• How much of the cigarette you smoke
• How long you have smoked
Your risk decreases significantly when you quit smoking. Twenty years after
you quit smoking your risk for lung cancer will be down to that of a non-smoker.
Another leading cause of lung cancer is exposure to radon gas. Radon is a naturally
occurring gas that is found in rocks and soil, but can also be found in the home. Because it
is found in rocks, people that work in mines can often be susceptible to lung cancer.
Passive smoking is also known to cause lung cancer in some people. Passive smoking is
the act of breathing in someone else’s smoke (from cigarettes). In doing this, one exposes
his or her lungs to the same risks that come in smoking. Although the exposure to smoke
from passive smoking is small compared to that of a smoker, the risk is still present. This
is especially true if you have a family member that smokes around you. This significantly
increases your risk of developing lung cancer, because of the increased exposure to their
The last major cause of lung cancer is exposure to asbestos. Asbestos is a mineral
made up of many tiny fibers. When it is disturbed, the fibers form a dust. This dust can be
inhaled, and can remain in the lungs for decades.
There is also a higher risk for people to develop lung cancer if their family has a
history of lung cancer.
There are many symptoms associated with lung cancer. They range from mild and
harmless to painful and dangerous. The following symptoms are the most common ones that
people experience with lung cancer:
• Shortness of breath
• Coughing up blood
• Incessant cough
• Chest or abdominal pain
• Weight loss (loss of appetite)
• Hoarse voice
• Clubbing of the finger nails (slightly less common than others)
• Difficulty swallowing
Sometimes the cancer can also grow into the airway, which can cause breathing
difficulty, and, as mentioned before, wheezing. The cancer can also have a very abundant
blood supply. Because the cancer has a weak surface, it can be ruptured, and this can cause
blood to flow into the airway, which can subsequently be coughed up.
There are a number of different ways lung cancer can be diagnosed. The doctor can
perform a simple physical exam. This will not prove that the patient has cancer, but it will give
the doctor an idea, and the patient will receive further tests. Another method is the chest x-
ray, which shows the contents of the lungs, and whether or not a tumor rsides in either lung.
The tumors can sometimes be in the early stages of growth, and can be difficult to detect, so
doctors can sometimes overlook them. The last major form of diagnosis is a biopsy, which can
come in multiple forms itself. These variants are a bronchoscopy, a needle biopsy, and
Here is a cross-section x-ray of a normal lung, with no visible presence of a
Here is another cross-section of the same lung two years later. There is clearly an
obstruction in the right hand side of the lung. A doctor would probably recognize this as a
tumor in the early stages of development.
Here is another cross-section x-ray of the same lung, in an x-ray taken two years later.
The then-small tumor has become a massive one in the right lung. This tumor would be
virtually untreatable, and the patient would probably die.
There are a number of different treatments for lung cancer:
If the cancer hasn’t spread to both lungs, or to other parts of the body, surgery is a
viable option for treatment. There are multiple procedures to remove the tumor:
o Lobectomy: The removal of one lobe
o Bilobectomy: The removal of two lobes
o Pneumonectomy: The removal of an entire lung
If the surgery is a success, the prognosis for the patient is relatively good. The 5-
year prognosis is 70%.
Segmental resection is the removal one or more segments of a lobe of a lung.
As with lobectomy, the tissue removal is guided by anatomical planes, but in this
procedure, the dissection is much more extensive. This procedure is often done in
patients with borderline pulmonary function in order to preserve as much lung
tissue as possible. Segmental resection is typically performed to remove a bleb,
localized abscess, or small tumor. Because of the complexity of this surgery,
patients are more likely to have air leaks through the chest tube (s)
postoperatively and may have delayed re-expansion of the remaining lung tissue
on the surgical side. Therefore, careful attention to postoperative pain control and
respiratory care to reduce the risk of atelectasis or nosocomial pneumonia is
particularly important. One or two chest tubes may be in place after the
procedure. Watch for intermittent bubbling in the water seal chamber which can
indicate a persistent air leak along the suture line on the lung. (Description of surgery
from Clinical Update for the Professional Nurse)
Description: A Segmental resection
Wedge resection is the removal a small, triangular piece of lung tissue near
the lung surface. This procedure is typically done for lung biopsy or to remove a
small, well-defined lesion. Usually a single postoperative chest tube is in place to
allow air to escape from the pleural space. Postoperative bleeding is typically
minimal. . (Description of surgery from Clinical Update for the Professional Nurse)
Lobectomy is the removal of one lobe of one lung is a relatively
straightforward surgical procedure because the demarcation along anatomical
borders is clear. This procedure is typically chosen when a lesion is clearly
limited to one lobe of one lung — a tumor, cyst, abscess, traumatic injury, or
bronchiectasis. Expect one or two chest tubes postoperatively to drain both air and
fluid from the chest. . (Description of surgery from Clinical Update for the Professional Nurse)
Pneumonectomy is the removal of an entire lung, most commonly to treat lung
cancer. . (Description of surgery from Clinical Update for the Professional Nurse)
Lung volume reduction
Lung volume reduction is a procedure designed to treat emphysema, currently
under study in a number of select centers across the United States. Removing
sections of hyper-inflated lung tissue may reduce dyspnea and improve lung
function in patients with advanced emphysema. Outcomes have been variable and
seem to depend largely on initial patient selection. Chest tubes are required
postoperatively; postop air leaks resulting from sutures or staples placed in friable
lung tissue can be particularly difficult to manage. . (Description of surgery from Clinical
Update for the Professional Nurse)
Thoracoplasty is not technically lung surgery — it is a procedure done on the chest
wall in which one or more ribs or rib segments are removed to reduce the size of the
thorax. This procedure is rarely done today, but we may care for patients who underwent
this procedure in the 1950s when it was a common treatment for chronic tuberculosis.
Chemotherapy is used mainly for small-cell lung cancer, because there is a good
response to this treatment with small-cell lung cancer. Chemotherapy is the use of
special anti-cancer drugs, also known as “cytoxic” drugs to destroy existing cancer
cells. Chemotherapy is a global treatment. This means that the drugs can treat the
whole body, whereas other forms of treatments are local, meaning they only treat one
part of the body. Having a global treatment is important because it is likely that the
cancer cells will have spread to other parts of the body unbeknownst to the patient or
Description: Chemotherapy pills
Radiotherapy is the use of high-energy rays to kill cancer cells. It is sometimes
used alongside other treatments, most often chemotherapy. Radiotherapy can be used
to shrink a tumor, which will later be removed by surgery.
Radiotherapy works by bombarding cancerous cells with rays that disrupt its
duplication. It partially disables the cancerous cells from duplicating at their normal
rate, and makes DNA replication difficult. Because of this, radiotherapy has many
unpleasant side effects, such as hair loss, and skin disorders. This is because these are
parts of the body that also reproduce very often, and the radiotherapy disrupts them as
it does the cancer cells.
This type of treatment can be used when the patient’s tumor is inoperable. The
first stage of this treatment is the injection of a drug that is triggered by light, such as
lumin. Then, a bronchoscopy is performed. A bronchoscopy is the insertion of a
scope that is used to examine the airwaves. When the scope is near the tumor, it emits
light of a specific wavelength. This then sensitizes the tumor, and a laser is then
directed toward the tissue, and destroys it.
Electrosurgery is the use of a disk, bulb, or needle to direct electrical energy at the
cancerous cells to destroy them.
Internal Radiation Therapy
The radiation is swallowed, injected, or implanted directly into the tumor inside the
body as close to the cancer as possible. These substances that produce radiation are called
radioisotopes. Internal radiation gives you a high dose of radiation in a shorter time than
with external radiation. Some internal radiation is permanent and some are temporary. In
some cases, both internal and external are used.
External Radiation Therapy
An example of External Radiation Therapy would be External Beam Radiation
Therapy (EBT). It is a method that delivers a beam of high-energy x-rays to the location
of the tumor. These x-rays can destroy all of the cancer cells.
Description: External Radiation Therapy
It is the use of extreme cold made by liquid nitrogen to destroy the abnormal tissue.
For external tumors liquid nitrogen is applied directly to the tumor with a cotton wipe or
spray. For internal tumors liquid nitrogen is circulated throughout the body with a hollow
instrument called a cryoprobe. The doctor uses a MRI or ultrasound to guide the
cryoprobe in its freezing process. After cryosurgery is performed on external tumors it
dissolves and forms a scab. After cryosurgery is performed on internal tumors it thaws
and is absorbed into the body.
Doctors will decide what treatment to give you based on the stage the tumor is at
in the lung. These stages take into account whether or not the cancer has spread to other
parts of the body, the physical size of the cancer, and whether or not the lymph nodes are
affected. The following table shows how the stage of the cancer is derived.
1a T1 No no
1b T2 No No
2a T1 Some No
2b T2 Some No
3a T1-3 Some No
3b T4 severe No
4 Any metastasis (spread through body)
*T=Tumor size (t1 is less than 3cm. t2 is greater than 3 cm), and tumor site (t3 is
invasion of chest wall, pleura, etc., T4 is invasion of mediastinum)
The treatment received is based on the stages described above. Stages 1a/b and
2a/b are both treated with surgery, because the tumor is localized, and removable.
Stage 3a is treated with chemotherapy, followed up by radiotherapy or surgery. Stage
3b is treated with a combination of chemotherapy and radiation therapy. Stage 4 is
treated with chemotherapy. The chances of survival if the cancer reaches stage four
Lung cancer can be treated through surgery, electrosurgery radiotherapy,
chemotherapy, internal and external therapy, photodynamic therapy, and cryosurgery.
Lung cancer patients have many options for treatments, but recovery depends on each
individual. Lung cancer can be beaten if the individual is willing to work to survive.
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