Hi Bob,
sending prayers for you right now... My dads pulmonologist once told us, if you have questions about the lungs, you ask the lung specialist, if you have questions about the cancer you ask the oncologist, and surgery you ask the surgeon, his point was to go to the one who specializes in the field that you are concerned about..
One thing I always hated about the hospitals is you could never get a straight answer, but it does sound like they have an idea of what is causing your problem, let us know what they come up with in the meantime I will keep you in my prayers...