Can Lupron injections for Prostate Cancer leak out the hormone if not administered correctly?

My dad gets Lupron injections for prostate cancer. The injection site is leaking quite a bit, has for the past 2 treatments (1 every 3 months). Based on other symptoms, we think his body isn't keeping the full injection, although the dr. says this isn't possible. Is it possible some of the actual hormone could leak out and not just the oil that it is packed in? Or is there a blood test that would measure the amount of hormone in his system vs. how much should be in his system?

Can Lupron injections for Prostate Cancer leak out the hormone if not administered correctly?
I was taking shots for 3 years. They hurt my hips so bad, I was in constant pain and walking was difficult. I switched to Lupron Depot, a capsule placed in arm, with 1 year effectiveness. I would have stopped treatment without this alternative. The cost is the same, but check with insurance, since some raters don't know what the procedure is. Good luck to all of you.