What is it?
First, some background on the way the body is built. Organs, like
the heart, liver, and lung, are made up of tissues, such as blood
vessels and muscle. Tissues, in turn, are made up of cells. Cells
are the basic building blocks of tissue. Cancer results from the
abnormal proliferation, or repeated divisions, of cells. The rapidly
dividing cells of a cancer grow in number, developing into a tumor,
or mass. A lung cancer develops when a group of cells in the lung
begins dividing rapidly, and creates an enlarging mass within the
lung. The size of the mass may double as quickly as every 30 days,
or as slowly as every 400 days, depending upon the type of cells
that are dividing, and on other factors. Different types of lung
cancer originate from different types of cells. These different
types of cells are identified by examining the cells under a microscope,
and performing special tests on the cells. (1)
If not treated early enough, most lung cancers have a tendency to
eventually spread to other areas of the body. The cancers can spread
through the lymphatic system to the regional lymph nodes (tiny filters
in the lymphatics), or through the blood, usually to bones or to
the brain. The location of distant spread is called a metastasis.
(1) The degree of spread of the cancer is known as the Stage of
the lung cancer. The stages of lung cancer will be discussed below.
Risk factors for lung cancer
The primary risk factor for lung cancer is cigarette smoking, and
exposure to cigarette smoke.(2) 87% of patients with lung cancer
have a history of tobacco exposure. The exposure can be either from
smoking cigarettes, or from inhaling second hand smoke. The risk
of lung cancer goes up with the number of cigarettes smoked per
day, and the duration of use of tobacco. This is measured typically
as pack-years, or the number of packs per day times the number of
years of smoking.
Other risk factors for lung cancer include exposure to environmental
agents such as asbestos and radon, (3) and exposure to other industrial
products. Asbestos exposure is linked to a tumor of the pleura called
mesothelioma. However, the combination of smoking and asbestos exposure
generates a risk factor for lung cancer that is greater than the
simple sum of the relative risks. Asbestos was used in the past
as an insulation material, and in automobile brake pads, and was
frequently used in shipyards. Radon is a naturally occurring gas,
a byproduct of the breakdown of uranium. Radon can be found in up
to 6 per cent of homes in the US. It is most frequently found in
unventilated basements, and in concrete buildings. Home tests for
radon are commercially available.
There are a number of other carcinogens (cancer causing agents)
that are believed to be associated with lung cancer, and are reviewed
Incidence of lung cancer
Lung cancer is the most frequent cause of death from cancer in both
men and women.(3) Lung cancer is responsible for more cancer deaths
in men than all other cancers combined.(ibid.) In the late 1980’s,
the incidence of lung cancer in women surpassed the incidence of
breast cancer due to the increasing use of tobacco by women. (ibid.)
The incidence of lung cancer can be reduced in large populations
by reducing the use of cigarettes. In England, the lung cancer rate
in men from ages 35 – 54 has dropped 50% in 30 years due to
the development of non-smoking programs. (4) An individual can reduce
his or her own risk by 50% by not smoking for 10 years.(5)
Most patients early in the course of lung cancer have no symptoms.
The cancer grows silently when it is very small. However, some patients
will develop symptoms of a persistent cough, hemoptysis (coughing
up blood), recurrent pneumonia, weight loss, wheezing, fever, or
pain. Sometimes a lump develops in the neck or armpit. A few lung
cancers secrete hormones or proteins that cause signs or symptoms.
By the time most lung cancers are discovered, 85% have spread beyond
the ability of the surgeon to remove them.(3) Therefore, prevention,
or early detection, when the cancer can still be removed, is important
to obtain a cure.
Categories of lung cancer
There are two general categories of lung cancer: small cell and
non-small cell. The categories are divided this way because they
act differently and are treated differently.
One basic type
Usually spreads early in
Stages: limited or extensive
Treated with chemotherapy
Three basic types - Adenocarcinoma,
Squamous cell carcinoma, Large cell carcinoma
Usually spreads later in
Stages: I, II, III, IV
Treated with surgery, chemotherapy,
and/or radiation therapy, depending on the stage.
Stages of Lung
The amount of spread of a cancer in the lung is measured by its
"stage." The further that cancer cells have spread from
the original mass, or the larger the cancer, then the higher the
The stage of a cancer determines the treatment that is selected
for that particular cancer, and the prognosis. The higher the stage,
the greater the spread. The greater the spread, the worse the prognosis.
Non-small cell cancer is staged using the TNM staging system. TNM
refers to T for tumor size, N for node status, and M for the presence
or absence of metastases. In general, there are Stages I, II, III,
I is a tumor that is localized to the lung, and has
no lymph node involvement.
Stage II is a tumor that has
lymph node involvement inside the lung only, or a tumor
which has grown directly into another nearby structure,
such as the chest wall.
Stage III is a tumor that
has spread to the lymph nodes in the mediastinum (the center
of the chest between the lungs.)
Stage IV is a tumor that has
spread anywhere outside the confines of the chest. That
is, tumor which has spread to the adrenal glands, bones,
ribs, brain, or elsewhere.(6)
The true diagnosis of lung cancer can only be made by looking at
cells from a mass or lymph node under a microscope. There are a
number of diagnostic tests that are performed in preparation or
in pursuit of making a tissue diagnosis.
Chest X-ray. The chest x-ray, also
known as a chest radiograph or CXR, is a screening test for lung
cancer. Many cancers are initially detected on a routine chest radiograph
that is taken for an annual physical or in the process of evaluating
another medical problem.
CT scan of the chest. The CT scan
is also known as a CAT scan, or computerized axial tomography. This
scan takes only a few minutes to perform, and gives a very detailed
image of the anatomy of the chest and lungs. It is used to evaluate
the location and size of tumors in the chest, and is used to evaluate
the size and location of lymph nodes in the chest. In addition,
the adrenal glands are usually evaluated with this test, because
the adrenal glands are an area where lung cancer can spread early
in its course.
PET scan. A PET scan is a test using injectable radioactive
material which is detected by a special camera. The most frequent
PET scan used for the lung measures the relative metabolism of glucose
by tissues in the body. Infections, inflammation, and cancers use
more glucose than surrounding tissues. This area of increased utilization
of glucose appears to the camera as more intense radioactivity than
surrounding areas on the scan (a "hot spot."). The PET
scan is not perfect at predicting cancer. It only creates significant
suspicion of cancer. In contrast, a PET scan that does not show
increased activity in a lung tumor is very reliable. The chance
of the nodule being a cancer in such a scan is very, very low.
Bone Scan. A bone scan is a test using
injectable radioactive material that is detected by a speical camera.
The bone scan is used to detect abnormal areas in the bones of the
body. Sometimes these areas are abnormal due to arthritis or other
changes, and sometimes due to spread of cancer to the bone. If an
abnormality is detected by bone scan, then further investigation
into the abnormal area may be necessary.
Bronchoscopy. Bronchoscopy is a procedure
done by Pulmonologists and Thoracic Surgeons. This procedure is
done under sedation in a special area of the hospital or outpatient
procedure suite. While the patient is sedated, a small, flexible
tube is advanced through the nose or mouth into the windpipe (trachea).
All of the visible branches of the windpipe (airways, or bronchi)
are examined, and biopsies of any abnormalities are performed. Sometimes
biopsies of lung tumors are performed, and occasionally lymph node
biopsies are done. The patient may return home on the same day of
the procedure. Coughing up small amounts of blood for a few days
after the procedure is not unusual.
CT directed needle biopsy. When a
lung tumor is located far away from the airways, and cannot be reached
by bronchoscopy and biopsy, another test may be performed. This
test is performed by a Radiologist with the use of a CT scanner.
The tumor is precisely located by using a CT scan. With the patient
still in the CT scanner, local anesthesia (numbing medicine) is
injected into the patient’s skin. Then, a small needle is
advanced directly into the lung tumor, and tumor cells are aspirated
into a syringe, then examined under a microscope. In the vast majority
of cases, there are no complications from a CT directed needle biopsy.
Occasionally a small amount of air leaks from the lung into the
chest, and the air must be removed by placing a small drain into
the chest for several hours or a for a day.
Procedure. Mediastinoscopy is an operation performed by a
Thoracic Surgeon in a surgical suite with the patient under general
anesthesia. Mediastinoscopy and the related procedures are used
to evaluate the lymph nodes in the mediastinum, the center of the
chest (media is derived from the Latin "medius" meaning
the middle, or center.) For more detailed information, please see
the related article on Mediastinoscopy.
The lymphatic vessels of the mediastinum carry lymphatic fluid from
the lungs, returning the fluid to the venous system of the blood.
This lymphatic fluid contains fluid and cells from the lung and
pleura. The lymph nodes in the mediastinum serve as filters for
lymph that leaves the lung. These filters act somewhat as a line
of defense against the spread of cancer, trapping cancer cells,
and preventing them from spreading further throughout the body.
The lymph nodes will actually try to kill the cancer cells in some
If cancer is present in the lymph nodes of the mediastinum, it means
that the cancer has spread outside of the lung itself. The presence
of cancer in the mediastinal lymph nodes makes the lung cancer a
Stage III. Stage III lung cancers are usually treated with chemotherapy
rather than surgery, with a few exceptions.
Thoracoscopy. Thoracoscopy is a surgical
procedure done by a Thoracic Surgeon. The operation is performed
under general anesthesia using a tiny endoscope, or fiberoptic camera,
to look inside the chest. The surgeons of Thoracic Surgery Associates,
PC, use a 5 mm endoscope, slimmer than a drinking straw, for this
operation. With the use of special instruments, a biopsy of the
lung, of the chest wall, or the mediastinal lymph nodes can be performed.
Thoracoscopy can be used to help determine the stage of a cancer,
and to treat some conditions associated with cancer, such as effusions,
or pneumothorax. For more detailed information, please see the article
on Thoracoscopy elsewhere in this site.
Thoracotomy. Thoracotomy is a surgical
procedure done under general anestheria by a Thoracic Surgeon. At
Thoracic Surgery Associates, PC, we utilize an incision approximately
six inches long, beneath the armpit, to go between the ribs and
into the chest. This incision allows complete access to the chest
to perform biopsies of the lung, the lymph nodes, or the chest wall.
In addition, if necessary, a large section of the lung can be removed
(a lobectomy.) For more detailed information, please see the article
on Thoracotomy elsewhere in the site.
Treatment of Lung Cancer
Decision making. The decision regarding
how a specific lung cancer is treated in a specific patient depends
upon the cell type, the location, and the stage of the cancer. The
collaboration of a medical oncologist, radiation oncologist, and
thoracic surgeon gives the patient every possible option for treatment.
Non surgical treatment. Stage III
B and Stage IV cancers are almost always treated with chemotherapy,
with or without radiation therapy. Surgery is not usually used for
lung cancers that have spread outside the chest.
Surgical treatment. Surgical removal
of lung cancer is usually reserved for non-small cell lung cancer
that is Stage I or II. There are a few Stage IIIA patients that
will benefit from surgery. Stage IV patients with non-small cell
lung cancer with a singe brain metastasis in the presence of a single
primary lung cancer may be candidates for surgery.
used for staging
Staging operations done by a Thoracic Surgeon. Such operations include:
- Chamberlain Procedure
These procedures are explained in detail elsewhere in the site.
Operations used for removal of a lung cancer
The removal of a lung cancer is done by a Thoracic Surgeon. The
operation is called a thoracotomy and lobectomy. A six inch incision
is made on the side or back of the chest, the large muscles of the
chest wall are moved out of the way, and a space is developed between
the ribs to gain access to the inside of the chest. The tumor mass
is located in the appropriate lobe of the lung. The blood vessels
leading to, and rising from, that particular lobe are ligated and
divided. Then, the bronchus (airway, or breathing tube) to the lobe
is divided, and the lobe, with the cancer and surrounding lymph
nodes in it, is removed. For a more detailed description, please
see the article elsewhere on the site.
Risks of surgery
. The immediate risks
of surgery of the chest include bleeding (which could require blood
transfusion), infection (which could require antibiotics or re-operation),
and pneumonia. The risk of surgery increases with worsening lung
function, worsening oxygen diffusion capacity, and age. In the immediate
post-operative period, the patient is at risk for pneumonia (made
worse by smoking, COPD, and chronic bronchitis), bronchitis, wheezing,
and irregular heart beats. Patients with chronic lung disease, heart
disease, or kidney disease are at increased risk of surgery, or
of worsening those conditions in the immediate post-operative period.
Some rarer risks include the risk of hoarseness, development of
a pulmonary hernia, and fluid collection under the skin (seroma.)
Recovery from surgery
that have staging procedures go home on the day of surgery.
Most patients that have thoracotomy lung resections stay in the
ICU the night of surgery. If recovering well, the patient will be
transferred to a surgical floor for the remainder of their stay.
Most patients will have a heart monitor for most of their stay.
Pain is controlled for the first few days with an epidural, and
later with a patient-controlled analgesia pump. The usual length
of stay after a thoracotomy is 5 to 7 days.
The rate of recovery is directly related to lung function and other
related medical problems. Usually, the patient will get out of bed
on the first post-operative day, and walk in their room the second
day. By the third day, most patients should be able to walk in the
Drains, called chest tubes, are left in place for 3 to 5 days to
remove excess air and fluid from the chest after surgery. These
drains are removed at the bedside when the drainage is sufficiently
diminished, usually around the third to fifth day after surgery.
We encourage our patients
to remain active at home after discharge. If the
patient remains sedentary, they are at increased risk for pneumonia
and for development of blood clots in the legs. Both of these conditions
can require readmission to the hospital for a prolonged period of
The first week at home, we encourage the patient to walk around
the house and the yard several times a day. The second week, the
patient should walk around the block, or its equivalent, about a
quarter of a mile a day. The third week, the patient should walk
up to a mile a day, in parts, or at one time.
We restrict driving for three weeks, or later, until narcotic pain
medicine is no longer needed.
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