A lung Positron Emission Tomography (PET) scan is an imaging test that uses a radioactive substance (tracer) to help detect diseases in the lungs, most commonly lung cancer.
Here's a more detailed breakdown:
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What it is: A PET scan is a type of nuclear medicine imaging. This means it uses small amounts of radioactive material to visualize and measure changes in metabolic processes, like glucose (sugar) uptake.
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How it works:
- A radioactive tracer, often fluorodeoxyglucose (FDG), which is similar to glucose, is injected into the bloodstream.
- Cancer cells, due to their rapid growth, tend to absorb more glucose than normal cells.
- The PET scanner detects the areas where the tracer accumulates, highlighting potentially cancerous or diseased tissues in the lungs.
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Why it's used:
- Detecting lung cancer: PET scans can help identify lung tumors, even small ones.
- Staging lung cancer: They can determine if the cancer has spread to other parts of the body (metastasis).
- Evaluating treatment response: PET scans can show whether lung cancer treatment (chemotherapy, radiation, etc.) is working effectively.
- Differentiating between benign and malignant lung nodules: PET scans can help determine if a lung nodule is cancerous or not.
- Identifying areas for biopsy: Areas that show increased tracer uptake can be targeted for biopsy to confirm the diagnosis.
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Important Considerations:
- Radiation exposure: PET scans involve a small amount of radiation exposure. The risks are generally low, but it's important to discuss any concerns with your doctor.
- Preparation: Your doctor will give you specific instructions on how to prepare for the scan, which may include fasting for a certain period of time.
- Combined PET/CT Scans: Often, PET scans are performed in conjunction with a Computed Tomography (CT) scan. This provides both functional (PET) and anatomical (CT) information, leading to a more precise diagnosis. This combined scan is called a PET/CT scan.
In summary, a lung PET scan is a valuable diagnostic tool that uses a radioactive tracer to identify areas of increased metabolic activity in the lungs, helping doctors detect, stage, and monitor lung cancer and other lung diseases.
