Lung Cancer Diagnosis
Learn about how your doctor can diagnose and treat lung cancer.
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Doctors divide lung cancer into two main types based on how the cancer cells look
under a microscope. The two types are small-cell lung cancer and non-small cell
lung cancer, which is more common. According to the American
Lung Association, lung cancer is the leading cause of cancer deaths for
both men and women in the United States.
If you think you have the symptoms of lung cancer, see your doctor
immediately. Your doctor will evaluate your medical history, assess any risk
factors you have, and perform a physical exam. Your doctor may then recommend
additional testing if necessary.
Lung cancer testing can be invasive and can put people at an unnecessary
risk. However, since people don’t usually exhibit symptoms until the disease
has advanced, screening for it can help detect it early on, when it has a
higher chance of curative treatment. Generally, your doctor will recommend a screening
test only if they’ve found a reason to believe you might have it.
Diagnosing lung cancer
Your doctor will check your vital signs like oxygen saturation, heart rate,
and blood pressure, listen to your breathing, and check for a swollen liver or lymph
nodes. They may send you for additional testing if they find anything abnormal
A CT scan is an X-ray that takes several internal pictures as it rotates
around your body, providing a more detailed image of your internal organs. It can
help your doctor identify early cancers or tumors better than standard X-rays.
A thin, lighted tube called a bronchoscope will be inserted through your
mouth or nose and down into your lungs to examine the bronchi and lungs. They
may take a cell sample for examination.
Sputum, or phlegm, is a thick fluid you cough up from your lungs. Your
doctor will send a sputum sample to a lab for microscopic examination for any
cancer cells or infectious organisms like bacteria.
Imaging tests can help your doctor detect masses and tumors. Some tumors can
have characteristics that are suspicious, but radiologists can’t be certain if
they’re benign or malignant. Only a biopsy can help your doctor determine if
suspicious lung lesions are cancerous. A biopsy will also help them determine
the type of cancer and help guide treatment. Several methods of lung biopsy
include the following:
- During a thoracentesis, your doctor inserts a
long needle to take a sample of fluid, called pleural effusion, between
the layers of tissue lining your lung.
- During a fine needle
aspiration, your doctor uses a thin
needle to take cells from your lungs or lymph nodes.
- A core biopsy is
similar to a fine needle aspiration. Your doctor uses a needle to take a
larger sample called a “core.”
- During a thoracoscopy, your doctor makes small incisions in your chest and
back to examine lung tissue with a thin tube.
- During a mediastinoscopy, your doctor inserts a thin,
lighted tube through a small incision at the top of your breastbone to visualize
and take tissue and lymph node samples.
- During an endobronchial
ultrasound, your doctor uses sound waves to guide a bronchoscope down your trachea or
“windpipe” to look for tumors and photograph them if they’re present. They’ll
also take samples from the areas in question.
- During a thoracotomy, your surgeon makes a
long incision in your chest to remove lymph node tissue and other tissue
Testing for the spread of lung cancer
Often, doctors use a CT scan
as an initial imaging test. It involves the injection of contrast dye into the
vein. CT gives your doctor a picture of your lungs and other organs where the
cancer may have spread like your liver and adrenal glands. Doctors also often
use CT to guide biopsy needles.
Other tests may be necessary to determine if and where cancer has spread, or
metastasized, in the body:
- Doctors may order an MRI when they suspect lung
cancer may have spread to the brain or spinal cord.
- A positron-emission
involves the injection of a radioactive drug, or tracer, which will
collect in cancer cells, allowing your doctor to see the areas with cancer.
- Doctors only order bone scans when they suspect cancer has spread to
the bones. It involves injecting radioactive material into your vein,
which builds up in abnormal or cancerous areas of the bone. They can then see it on imaging.
of lung cancer
The stage of lung cancer describes the progression or extent of the cancer.
If you receive a lung cancer diagnosis, the stage will help your doctor come up
with a treatment for you. Staging doesn’t solely indicate the course and
outcome of your lung cancer. Your outlook depends on your:
- overall health and performance status
- other health conditions
- response to treatment
Lung cancer is mainly classified as either small-cell or non-small cell
lung cancer. Non-small cancer is more common.
Stages of small-cell
Small-cell lung cancer occurs in two stages called “limited” and “extensive.”
The limited stage is confined
to the chest and is usually in one lung and neighboring lymph nodes. Standard treatments include chemotherapy and radiation therapy.
The extensive stage involves both lungs and other parts
of the body. Doctors usually treat this stage with chemotherapy and supportive care. If
you have this type of lung cancer, you may want to see if you're a candidate for a clinical trial designed to evaluate the efficacy and safety of new drugs.
Stages of non-small
cell lung cancer
- In the occult stage, lung cancer cells are in sputum or in a sample collected
during a test but no sign of a tumor in the lungs is present.
- In stage 0, cancer cells are in the innermost lining of the lung only
and the cancer isn’t invasive
- In stage 1A, cancer is in the innermost
lining of the lungs and deeper lung tissue. Also, the tumor is no more than 3
centimeters (cm) across and hasn’t invaded the bronchus or lymph nodes.
- In stage 1B, the cancer has
grown larger and deeper into the lung tissue, through the lung and into the
pleura, is more than 3 cm in diameter, or has grown into the main bronchus but hasn’t
yet invaded the lymph nodes. Surgery and sometimes chemotherapy are treatment
options for lung cancers in stage 1A and 1B.
- In stage 2A, cancer is less than 3 cm in diameter but has spread to the
lymph nodes on the same side of the chest as the tumor.
- In stage 2B, the cancer has grown into the chest wall, main bronchus,
pleura, diaphragm, or heart tissue, is more than 3 cm in diameter, and may also
have spread to the lymph nodes.
- In stage 3A, the cancer has spread to the
lymph nodes in the center of the chest and on the same side as the tumor, and
the tumor is any size. Treatment for this stage may involve a combination of
chemotherapy and radiation.
- In stage 3B, the cancer has invaded the
lymph nodes on the opposite side of the chest, the neck, and possibly the
heart, major blood vessels, or esophagus, and the tumor is any size. Treatment
for this stage involves chemotherapy and sometimes radiation
- In stage 4, the lung cancer has spread to other areas of the body,
likely the adrenal glands, liver, bones, and brain. Treatment for this stage
involves chemotherapy, supportive, or comfort, care, and possibly a clinical
trial if you’re a candidate and you choose to participate.
What is the outlook?
See your doctor immediately if you suspect you may
have lung cancer. Many tests are available to confirm a diagnosis and to
identify what stage the cancer is at if you do have cancer. Detecting cancer
early on can help your doctor treat the cancer at an earlier stage and more effectively.
Whatever stage the cancer is, treatment is available.
The Healthline Editorial Team
Medically Reviewed by:
Monica Bien, MPA, PA-C
Oct 2, 2014
Published By: Healthline Networks, Inc.