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"Are all lung lesions cancerous?"

ZocdocAnswersAre all lung lesions cancerous?


My doctor ran a chest x-ray on me to look for tumors, and didn't find any. (I'm a lifelong smoker, and I've been having trouble breathing.) Now he wants to give me a CT scan to check for 'lesions'. Is this just another way of saying 'cancer'? What do we do if he finds one?


First of all, not all lung lesions are cancerous. In fact, the majority of lung nodules (discrete opacities less than 3 centimeters in diameter that are completely surrounded by lung tissue) are completely benign. The chances of a lung nodule being malignant (i.e. cancerous) increases with age. Lung nodules in patients less than 40 years old are malignant approximately 3 percent of the time, whereas they are malignant more than 50 percent of the time in patients older than 60 years. Typically a lung nodule has to reach 1 centimeter in diameter before it can be visualized on a regular chest x-ray. A CT scan will be able to pick up smaller nodules (as small as 3-4 millimeters), characterize any lesions that are found (cancerous lesions often look different than benign causes), and also help define any abnormalities of the airways themselves. If a lesion is found, the course of action will depend on how big it is, what it looks like, and how accessible it is to possibly biopsy. Sometimes follow-up imaging in 3-6 months is recommended. Sometimes biopsy is performed, and sometimes other imaging such as PET scanning is done to help determine if a lesion is cancerous. If you are a lifelong smoker who is now having difficulty with breathing, it is certainly important to have this imaging done to rule out cancer. However, it is also important to consider the possibility that you are experiencing some obstructive lung disease as a result of your smoking (commonly referred to as emphysema). To help determine if this is the cause of your breathing difficulties, you can ask your doctor about pulmonary function testing.

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