Primarily used in the diagnosis, staging and treatment of lung cancer, a PET scan is a visual diagnostic tool. PET stands for position emission tomography and is a type of imaging test that utilizes radioactive tracers to show the composition of the imaged area. A PET lung scan is useful for visually examining the tissues of the lungs in a way that traditional MRI and CT scans can not.
A PET lung scan refers specifically to a PET scan of the lungs, but PET scans are sometimes done to diagnose other conditions in other areas of the body. The PET lung scan process involves injecting small traces of radioactive material into the veins, waiting until the substance is absorbed by the body and collected in the lungs. The patient is then placed inside a machine that records the radioactive energy and converts it into a computerized, three-dimensional image of the lungs.
In terms of diagnostics, a PET lung scan may be the most accurate source of information for the purpose of diagnosing or staging lung cancer. The test can tell doctors whether tumors detected during other imaging tests are cancerous, whether cancer has spread, or whether tumors are shrinking in response to treatment. There may also be other, non-cancerous conditions or diseases of the lungs that are diagnosed with PET scan technology.
While the usefulness of PET scans as a diagnostic tool is unquestioned, the expense of conducting such a test is greater than other imaging tests like an x-ray or CT scan. As a result, these more traditional imaging tests are typically performed first and during initial diagnostics. In the event that further data is necessary or a diagnosis can not be confirmed using other forms of imaging, a PET scan is likely to be ordered.
A PET lung scan is not painful and requires little preparation. Most patients will be told to refrain from eating for four to six hours prior to their scheduled testing time. Before the PET scan, patients should tell their doctor about any prescription or over the counter medications that they take since some medications may interfere with the test. Expect the test to take between 90 and 120 minutes, including the time spent waiting for the tracer to become fully absorbed. There is little if any discomfort involved and the risks from radiation exposure are fairly low. The results of a lung PET scan can be very useful to a doctor diagnosing and treating lung diseases.
