When in my late teens or early 20's I had pilondial cyst. I was defered from the draft because of it. Up to that time I didn't know what it was. It was painful to sit and it did drain ocassionally. One day it broke discharging puss and hairs. By pushing on it I got out all of the material that it contained. The cyst never has returned but I still have a small indentation where the cyst once drained. That was about 48 years ago.