I Have A Lump About The Size Of An Egg

I have a lump about the size of an egg deep inside my right bum cheek. I have had deep massage treatments as well as my chiropractic work to relieve it thinking it is a muscle adhesion. I also have been r
Working with a roller and a ball to try to get it to relieve. After almost 2 years I am wondering if it is a lump and not related to a tight muscle. I get pain radiating down the side of my leg like a sciatic nerve issue but it isn't that. What do you think.