If it is calcified, then it can be caused by a lot of things. Do you have night sweats, low grade fever and cough? Any symptoms? If you have these it could be due to a past infection with TB. You can have a nodule in the lung without it becoming active TB. TB can be dormant until you become immunocompromised then it can come out as disease. Also, dense calcified nodules can be due to inhalation of asbestos, coal , and other chemicals and the body walls it off. Other things it can be are sarcodosis, and haemosiderosis. Are they going to do a biopsy? At this point I can't say what the percentage it is of any of these things. It depends on what you or you and your famliy have been exposed to.
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