A:I have a similar, perfectly round, often sore lump in each of my armpits and was told it's a cyst caused by inflamed sweat glands...and as the crotch tends to sweat a bit this could be your problem as well. I was told they're harmless and rather simple to remove, but you should have it checked by a doctor since it could be the result of hemorrhoids or stds like the others said.
