Re: pituitary tumor?
That testing is for acromegaly. It is for too much growth hormone. I have the opposite in that I have low growth hormone. But I had the same test. It works for both. You are to be fasting, not to have exercised within 12 hours before the test and to be relaxed. It is not a bad test at all as you just have to wait as they take blood at timed intervals. They will,depending on the type of test, give you a med to stimulate growth hormone. So they take one or two baseline tests, give you the med, then at timed intervals, take more samples.
Your symptoms are consistent with a pituitary tumor. DHEA is produced in the adrenal but sometimes there is a cascade effect - for instance if the tumor is on an ACTH portion of the pituitary, it may not be sectreting that hormone but it may effect that part of the pituitary by putting pressure on it.
I don't think the sinus problems are related though. I had them and had a separate sinus surgery. The pituitary and sinuses are separated by bone and it would take a huge tumor to go through that and your eye sight would be effected first usually. An MRI would give you an indication of size. They are usually quite tiny. I had two - cushing's and prolactinoma.
Good luck on your testing.