To find out if lung cancer may be present, the doctor evaluates a person's medical history, smoking history, their exposure to environmental and occupational substances, and family history of cancer. The doctor also performs a physical exam and may order a chest x-ray or other tests. Seeing a spot on a chest x-ray is usually how a doctor first suspects that lung cancer may be present.
If lung cancer is suspected, the doctor may order a test called a sputum cytology. This is a simple test where a doctor examines a sample of mucous cells coughed up from the lungs under a microscope to see if cancer is present. But to confirm the presence of lung cancer, the doctor must examine fluid or tissue from the lung. This is done through a biopsy -- the removal of a small sample of fluid or tissue for examination under a microscope by a pathologist. A biopsy can show whether a person has cancer. A number of procedures may be used to obtain this tissue.
Bronchoscopy -- The doctor puts a bronchoscope -- a thin, lighted tube -- into the mouth or nose and down through the windpipe to look into the breathing passages. Through this tube, the doctor can collect cells or small samples of tissue.
- Needle Aspiration -- The doctor numbs the chest area and inserts a thin needle into the tumor to remove a sample of tissue.
- Thoracentesis - Using a needle, the doctor removes a sample of the fluid that surrounds the lungs to check for cancer cells.
- Thoracotomy -- Surgery to open the chest is sometimes needed to diagnose lung cancer. This procedure is a major operation performed in a hospital.
Doctors may also use imaging methods such as a spiral CT scan or a PET scan to look for signs of cancer. A CT scan, also known as computerized tomography scan, is a series of detailed pictures of areas inside the body. A PET scan, also known as positron emission tomography, is a computerized image of the metabolic activity of body tissues.
Other tests can include removal of lymph nodes for examination under a microscope to check for cancer cells. Lymph nodes are small, bean-shaped structures found throughout the body. They filter substances in a fluid called lymph and help fight infection and disease.