My father 63years old is healthy and only had spondolysis for several years. He has been taking medication for the same. Recently he was diagnosed with Thymoma (5.5x5.3 cm in axial section). The IHC done thrice confirmed it to be benign however he has nodules on his lungs which are 1mm to 2mm (per PET scan these nodules are metabolically inactive) and the surgical oncologist isn t willing to accept it as benign. He is of opinion that its malignant and has metasised and spread to the lungs. He also suggested that removal of Thymoma is a risky surgery as if we remove the primary mass, the nodules on the lungs will grow uncontrolled. Also if we leave the mass as it is, it can grow and compress the main arteries and heart. And in cases of malignant Thymoma, chemo usually does not give good results. This has caused a lot of confusion and since a month (14th april 2017 diagnosis) , we are just taking opinion after opinion from different doctors.l but no satisfactory results as of now. My father was a smoker for a little a long time and has quit for over 7-8years now. I just don t want to take any decision which can impact his current healthy life. You valuable suggestions are requested. Let me know if you may need anything further.