I can not help you, but I know others on here who can. I will say prayers for your FIL. I do know that my Drs are always checking my lungs and if they the slightest wheeze or rumble they get my an x-ray right away. Possibly for metastasis. Not saying that is what it is. It could also be the start of pneumonia. I have had that before and had to have several x-rays through the coarse of treatment as they wanted to make sure it was going away and not anything else.