Gideon Purchase's appearance today of a happy, lively 2-year-old hides the long battle he's fought for most of his life.
At six months of age, he began losing his appetite and wasn't sleeping. More fussy than usual, his parents thought all of the symptoms were related to teething.
Then a yellowish bruise appeared over one eye. The next day, it covered both eyes and a lump appeared on his head.
A quick visit to the doctor resulted in a devastating diagnosis for his parents – stage 4 high-risk neuroblastoma.
"It's literally as bad as it gets," Gideon's mother Katie Purchase told NBC's Today.
The boy was taken by Medivac to St. Jude Children's Research Hospital in Memphis, Tenn., where scans revealed the spread of the disease.
"His entire face and skull was full of cancer, and all of his bones were full of cancer," recalled St. Jude physician Dr. Sara Federico. "He had a large tumor that was present in the middle of his body."
Luckily for Gideon, St. Jude doctors had a plan to attack the cancer that was growing in his body.
They treated Gideon using a new technique combining an antibody with chemotherapy at the beginning, middle and end of treatment.
"The early results are surpassing all of our wildest expectations," Federico said.
Within six weeks of the new clinical trial, Gideon saw amazing progress.
"He went from 84 percent of his marrow having tumor to zero percent," Federico explained.
The tumors on his face, arms, and legs completely disappeared and others had dramatically shrunk. However, Gideon still had to undergo a bone marrow transplant and follow up radiation treatments.
"Being how aggressive this disease is, they can't leave one cell alive," his father, Gary, said.
After 15 months of treatment, Gideon's doctors finally declared him healthy.
"You yearn for the day when you're not toting around an entire IV tree behind your kid," Gary said. "And then it happens, and you just kind of sit there like, 'Wow. We made it!'"
Today, Gideon is a cancer-free, rambunctious young boy. His parents say they appreciate every moment with him.
"It makes you appreciate the little things. Suddenly, life's problems just don't seem like a big deal anymore," Gary said. "He makes us treasure every day."