Hello thanks for posting here. I have gone through your history and I do understand your concern. As you said, the PET CT shoes that it has no FDG uptake and hence called a bening one, however it still needs investigation. The cause for the nodule should be evaluated as it may be as a result of infection including TB (Tuberculosis) or due to an autoimmune process in which the body attacks its own cells. So a biopsy of the nodule should be done wither under CT guidance or by bronchoscopy whichever makes the nodule well accessible. Biopsy should be able to identify if its an infective process or autoimmune process and also br able to identify the cells and rule out malignancy. After biopsy if you get no answers, then you should not worry and follow up the nodule for increase in size by chest x ray or CT every 3 months to see the doubling time of the nodule. In the meanwhile please continue your genetics evaluation.