I had one last year that was spotted when I had a scan of my hip. Got the lovely "dildo cam" (love that description!), my doc decided to just keep an eye on it. Went back every three months to verify it wasn't growing. It's not, so we're ignoring it. AFIK, it's disappeared on it's own.

Now, my mom, and a friend I used to work with, had massive cysts. Mom's was grapefruit sized, V's was huge, went up into her ribcage and weighed 8 pounds.