The report on my CXR lists: Aprroximate 6.0CM X 5.0CM lucency seen in the medial aspect of the right middle lobe. Thought to represent a pneumatocele or cyst or bleb. I am in my 50s, no symptoms, no prior CXR to compare(at least not in the last 35 years). Should I forget about it, as my doctor recommends? He thinks I may have had it my whole life.