I'm sorry but I'm still confused.
Or maybe I missed the info somewhere.

Do the dr s say it is fluid building up that causes the swelling, or some other type of tissue overgrowth? Or they have no clue....

If excess fluid is the case why not insert a "drain" of sorts?
Or a "water pill" or something to see if it helps.

If tissue growth,
I can see why they might not want to do exploratory surgery due to possible spread, but if it is pretty much body wide already... it might be worth it to ease your discomfort.