The narcotics don't work for this, they will simply get you addicted.
My brother just spent a 2 months going dr to dr. He was on massive amounts of percocet but hadn't moved to oxycontin yet. And he was treated as a "drug seeker".
When they finally identified it, they realized he needed a long term epidural immediately. He had it the next day. Right now they are in "wait and watch", surgery scheduled for the future but if they wait too long it will destroy the vertebrae if wraps totally around it.
I believe these respond well to a tiny bit of alcohol surgically dropped into it, rather than carving it out. At least that is the plan for my brother, you might want to double check the alternative surgical approaches for this and if they apply in your situation.
For those that were at the wedding, this is the brother that gave the speech.
Note: My OTHER brother (the one that blew you guys away at the table) is legally blind due to this type of cyst putting pressure on his optic nerves. Do NOT ignore it. Benign doesn't mean it won't fuck you up.