Anything with the word "cyst" in it, I think of using straight iodine and DMSO. Dr. Jonathan Wright most frequently mentionss a 50/50 mix of SSKI and DMSO, but if I didn't have any SSKI I'd use whatever iodine I did have -- depending on how badly it stains. You can mix them together and use, or rub on a drop of iodine and follow with a rub of DMSO. I'd use 70% DMSO, as the 99% might be too strong to be used a couple times a day. DMSO carries the iodine into the skin and so would help penetrate the cyst. Breaking up cysts all around the body is what iodine does.