Kirsten, when I had my tumor they thought first it could be at the pit. gland as it was very close. So I went to see a hormone specialist. I remember that he said a tumor of this gland is difficult to get out as the gland itself is about the same size as the tumor. And if you hurt the gland the hormone consequences could be not so nice. You need these hormones to keep your weight e.g. and the substitution is so expensive -at that time more than 100.000 something per year (it should have been Deutsche Mark time, isn't it?)- that no insurance will come up with it.
So maybe leaving it as it is is the best solution.