look for cancerous cells and to rule out other conditions a number of
test can be done if lung cancer is suspected in a person. These include:
History and Physical Examination:
The presence of symptoms or signs that are suspicious for lung cancer
be revealed by a physical examination and history of the person. Signs
of breathing difficulties, airway obstruction or infections in the lungs
can be detected by asking about symptoms and risk factors for cancer
development such as smoking.
In chronic disease of the lung, due to
insufficient oxygen in the blood there may be a bluish color of the skin
and the mucous membranes. Changes in the tissue of the nail beds known
as clubbing, also may indicate chronic lung disease.
any new symptoms of lung cancer are present, the most common first
diagnostic step is chest X-ray. The back to the front of the chest as
well as a from the side can be viewed by this procedure. Chest X-rays
may reveal suspicious areas in the lungs but are unable to determine if
these areas are cancerous.
Calcified nodules in the lungs or benign tumors called hamartomas may be identified on a chest X-ray.
CT (computerized tomography) Scan:
examine for both metastatic and lung tumor CT scans may be performed on
the chest, abdomen, and/or brain. CT scans are X-ray procedures that
combine multiple images with the help of a computer to generate
cross-sectional views of the body. The test is more sensitive than
standard chest X-rays in the detection of lung nodules.
CT scans of
the abdomen may identify metastatic cancer in the liver or adrenal
glands, and CT scans of the head can reveal the presence and extent of
metastatic cancer in the brain.
Magnetic resonance imaging (MRI) scans:
precise detail about a tumor's location is required, MRI scan is done.
The MRI technique uses magnetism, radio waves, and a computer to produce
images of body structures. There are no known side effects of MRI
scanning and there is no exposure to radiation. The image and resolution
produced by MRI is quite detailed and can detect tiny changes of
structures within the body.
People with heart pacemakers, metal
implants, artificial heart valves, and other surgically implanted
structures cannot be scanned with an MRI because of the risk that the
magnet may move the metal parts of these structures.
Positron emission tomography (PET):
is a specialized imaging technique that uses short-lived radioactive
drugs to produce three dimensional colored images of those drugs in the
tissues within the body.
PET scans measure metabolic activity and the
function of tissues. PET scans can determine whether a tumor tissue is
actively growing and also determine the type of cells within a
PET scanning may also be integrated with CT
scanning which is known as PET-CT scanning. Integrated PET-CT has been
shown to improve the accuracy of staging of lung cancer over PET
Bone scans are used to create
images of bones on a computer screen or on film. This is done to
determine whether a lung cancer has metastasized to the bones. In a bone
scan, a small amount of radioactive material is injected into the
bloodstream and collects in the bones, especially in abnormal areas. The
radioactive material is detected by a scanner, and the image of the
bones is recorded on a special film for permanent viewing.
you have a cough and are producing sputum, looking at the sputum under
the microscope can reveal the presence of lung cancer cells.
cytology examination can be done if a tumor is centrally located and
has invaded the airways. This is the most risk-free and inexpensive
tissue diagnostic procedure. But since tumor cells will not always be
present in sputum even if a cancer is present it is not useful always.
The noncancerous cells may also look like cancer cells when they undergo
changes in reaction to inflammation or injury.
of the airways through a thin, fiberoptic probe inserted through the
nose or mouth is known as bronchoscopy. The procedure may reveal areas
of tumor that can be sampled (biopsied) for diagnosis by a pathologist. A
tumor in the central areas of the lung or arising from the larger
airways is accessible to sampling using this technique.
but rare complications of this procedure include a greater amount of
bleeding, decreased levels of oxygen in the blood, and heart arrhythmias
as well as complications from sedative medications and anesthesia.
biopsies are particularly useful when the lung tumor is peripherally
located in the lung and not accessible to sampling by bronchoscopy. A
thin needle through the chest wall is inserted into the abnormal area in
the lung and cells are suctioned into the syringe and are examined
under the microscope for tumor cells. A small risk of an air leak from
the lungs is there in this procedure.
lung cancers involve the lining tissue of the lungs (pleura) and lead to
an accumulation of fluid in the space between the lungs and chest wall,
this test is done. A sample of this fluid can be taken with the help of
a thin needle which may reveal the cancer cells and establish the
Major surgical procedures:
If none of the above
mentioned methods yields a diagnosis, surgical methods must be followed
to obtain tumor tissue for diagnosis.These can include:
which is examining the chest cavity between the lungs through a
surgically inserted probe with biopsy of tumor masses or lymph nodes
that may contain metastases.
- Thoracotomy is a surgical opening of the chest wall for removal or biopsy of a tumor.
mediastinoscopy and thoracotomy carry the risks of major surgical
procedures and complications such as bleeding, infection, and risks from
anesthesia and medications.
These test may reveal biochemical or metabolic abnormalities in the body that accompany cancer. These can be
- Elevated levels of calcium or alkaline phosphatase may accompany cancer that is metastatic to the bones.
levels of aspartate aminotransferase (AST or SGOT) and alanine
aminotransferase (ALT or SGPT) which are normally present within liver
cells, indicates liver damage.
genetic testing is done to look for genetic mutations in the tumor for
advanced NSCLCs. Testing may be done to look for mutations which are
responsible for tumor growth or abnormalities in the epithelial growth
factor receptor (EGFR) and the anaplastic lymphoma kinase (ALK) genes.
Other genes that may be mutated include MAPK and PIK3.