Hello from JustAnswer.
The pain in the chest can be associated with asthma (or chronic bronchitis of other causes), although not directly due to the asthma, The spasm of the airways that is the essence of asthma will not cause chest pain. However, it is possible to get inflammation around the lung associated with asthma, which can cause pain. It is also possible that chronic asthma can cause musculoskeletal chest pain, because the muscles in the chest have to work harder.
Since the white area on the first chest x-ray was found to be inflamed airways and a swollen vein on the CT scan and bronchoscopy, it is very likely that the white area on this recent chest x-ray is the same. The bronchoscopy is the most sensitive test to detect any abnormal growths in the major airways in the center of the chest, and the CT scan s the best method for identifying growths in the outer aspect of the lungs or growths in the center of the chest that arise outside of the airways, so you have had the best tests for assuring that there is no growth that is causing the finding on the chest x-ray.
At this point, with the recurrence of symptoms and findings on the chest x-ray, it would be appropriate to use steroids. Oral steroid would be appropriate to get rapid control of symptoms, but your doctor is correct that the use of a steroid inhaler would be appropriate for long-term management because it has less side effects.
If I can provide any additional information, please let me know.