A six-year-old Colombian boy, nicknamed "Turtle Boy because of a rare skin condition, has undergone life-changing surgery thanks to a British doctor.

Didier Montalvo suffers from congenital melanocytic nevus (CMN), which caused a giant mole to form on his back. Plastic surgeon Neil Bustrode successfully removed the mole, the Huffington Post said.

Bustrode told the Evening Standard that though CMN affected around one in 20,000 newborns babies, Didier's was the worst case he had seen.

"Effectively three quarters of the circumference of his body was affected," he said.

"Often people have CMN that are much flatter and are therefore much easier to care for and deal with."

After learning about Didier, the surgeon flew to Bogotá to treat him.

"When I saw the pictures of Didier, one of my first feelings was that if we could remove it, we would significantly improve his quality of life," he said.

Doctors were also concerned that the growth could become malignant.

"Obviously he has had to go through a number of painful operations but we feel it was worth it," he said. "It's great to see the photos of how Didier is getting on now. I'm really happy with how things have healed."

Didier has shown an astonishing recovery and is looking forward to living an ordinary life. His story is the subject of a special Channel 4 Bodyshock documentary.

"I want to grow up but the mole won't let me," Didier said before the surgery.

Didier hails from a poor and superstitious rural family and was denied proper treatment at an early stage.

The Mirror UK reported that it was after his story got featured in a local daily paper that enough donations started pouring in to pay for treatment.

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