What are the diagnostic tools for lung cancer?

When lung cancer is suspected, the diagnostic process begins with a complete medical history and compilation of a checklist of risk factors and symptoms. A physical examination is also given to provide other information about signs of lung cancer and other health problems.

Following these basic procedures, other diagnostic tools used to diagnose lung cancer may include:

• Chest X-rays are used to look for any mass or spot on the lungs.
• Other special X-rays use invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film. These can provide more precise information about the size, shape, and position of a tumor.
• Positron Emission Tomography (PET) scans are integral to lung cancer staging.  They determine whether the lung tumor is metabolically active (rapidly growing and consuming sugar), and whether there is spread of tumor to sites outside the lung.
• Computed tomography (CT or CAT) scan is a diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.
• Sputum cytology is a study of phlegm (mucus) cells under a microscope.
• Needle biopsy is the guiding of a needle into the mass (the tumor) while the lungs are being viewed on a CT scan. A sample of the mass is removed and evaluated in the pathology laboratory under a microscope.
• Bronchoscopy is the examination of the bronchi (the main airways of the lungs) using a flexible tube (bronchoscope) passed down the mouth or nose. Bronchoscopy helps to evaluate and diagnose lung problems, assess blockages, obtain samples of tissue and/or fluid, and/or to help remove a foreign body.
• Mediastinoscopy is a process in which a small cut is made in the neck so that a tissue sample can be taken from the lymph nodes (mediastinal nodes) along the windpipe and the major bronchial tube areas to evaluate under a microscope.
• X-rays and scans of the brain, liver, bone, and adrenal glands are taken to determine if the cancer has spread from where it started into other areas of the body.

A variety of other tests and procedures may be used as well.