Some background about me and the growth, in case it helps.
I've had it off and on for about five years. The lump is on the front/right side of my mons, about 1/2 an inch below where my pubic hair starts. I'm overweight, so I've got some padding around the lump. It might look a bit different in location on a thinner person. It gets larger right before I ovulate and again right before my period starts. It can disappear entirely for a couple of months, and then return with a vengeance. Usually it grows to about the size of an almond, although sometimes the size of an unshelled walnut. (Sorry for the nut comparisons, but they summarize both the size and shape.) At Christmas of this year, it was the size of a baseball cut in half and extremely painful, which is why I thought I had something Very Serious and saw a doctor. It's visible outside of my body when at its largest each month, and will sometimes bruise and hurt even more. (You can actually see if if I wear running tights, which is kind of inconvenient when I go to the gym for Pilates!)
I have pretty much all of the symptoms of endo save infertility, and I don't know if I'm infertile or not because I've never tried to have children. I've had heavy periods (bleed through a super plus tampon in an hour for a couple of days) since I was in my teens, and they are sometimes incapacitatingly painful. My period is accompanied by GI upset, although that's been greatly improved since I stoped eating wheat. Ultrasounds have ruled out endometrial hypertrophy, fibroids, and adenomyosis. Right now I have a Mirena which has brought my periods back into the heavy side of normal, but I need to get a new one soon. I
In terms of what I know about the surgery, I've been told I can have a local anaesthetic and they'll remove the lump, stitch up the tissue, and close the incision with superglue. Healing is very quick, and the only possible issue (aside from infection) is that I'll get some fluid buildup in the empty space.