MIAMI -

A teenager whose cancer is in remission helps other families cope when their young loved ones are diagnosed with cancer.

Andres Hidalgo was diagnosed with leukemia last year. He's one of the young patients who Dr. Guillermo De Angulo sees each day at Miami Children's Hospital.

Many, like Hidalgo, are diagnosed with leukemia, the most curable and common pediatric cancer that affects almost 3,000 children in the U.S. each year.

"Leukemia is a tumor that occurs in the bone marrow," explained De Angulo. "The bone marrow's a factory that makes blood and it's gone haywire and starts producing the wrong kind of cells."

At first, Hidalgo, 16, thought the flu was making him tired and sick, but he kept bruising from diving while playing volleyball.

"At first, it's kind of just like you're a deer in headlights," he said. "They kind of tell you 'cancer' and they start explaining stuff and just I don't even remember what the doctor said after that. I was kind of just so much in shock."

Hidalgo now volunteers at the hospital several times a week to meet with recently diagnosed patients and their families.

"There are things a child may not tell me or they may not tell their parents, but they will confide in someone else who has gone through the same difficult time," said De Angulo.

Seeing Hidalgo healthy also gives the parents hope.

"When I go, I try to smile and play with them because if they have a friend at the hospital, maybe it's just a little more more enjoyable to them," he added.

The high school junior is considering a career in medicine.

"If I got into medicine, then I'll be an oncologist, specifically a pediatric oncologist, because I know how these kids feel," he said.

Hidalgo continues to undergo chemotherapy once a month.