I feel sorry for your mother's sufferings. Left lung field white may mean obstruction of main bronchus of left lung or may mean pleural effussion due to cancer spread.
The cancer appears inoperable. However palliative treatment is always possible. If it is pleural fluid collection, it can be drained with a chest tube
and a pleurodesis
can be offered. It it is due to main bronchus obstruction, a LASER resection or local radiation
may help to open up the lung. In both cases, as the lung expands, the breathlessness will improve dramatically.
should also be tried. In some types of lung cancers, Chemotherapy gives very good response. What is her cell type?
If not a greater quantity, we can always offer her better quality of the remaining life. So focus on that aspect and don't be discouraged.