Tumor? Not that I know. In my case my Cushing's was caused by hyperplasia which does not show up on an MRI well - just a shadow so most radiologists do not see it. I have a friend who got growth hormone deficency from a car accident so trauma can also be the cause.

Treatments can be to make up for the absent hormones or surgery has to remove a tumor if it is causing too much of a hormone. I am panhypopitutary after pit surgery, thyroid surgery, adrenal surgery and ovarian surgery.. all were abnormal on me (oh and imaging said most if not all were largely normal, incorrectly, which is scary). I take every hormone but vasopressin. Some pills, some gels, some injections.