Adult circumcision is quite common in some countries. The African guys I met while traveling in South Africa, Lesotho and Swaziland all went through it. There is a cultural thing where the 17/18 year olds burn their clothes and possessions for a fresh start to adulthood, live in a hut in the mountains for a month or so learning about their ancestors and beliefs, then are cut by a traditional healer in an adulthood ceremony. With a sharpened spear, not a scalpel! It leaves an ugly scar and every year dozens of men die during the ceremony due to infection.