NEW YORK (CBSNewYork) — Scientists are reporting unprecedented success with a new type of cancer treatment. It uses the patient’s own immune system to fight the disease.

As CBS2’s Dr. Max Gomez reported, the revolutionary treatment is destroying cancer.

Emma Collins looks like a typical 16-year-old girl now, but less than three years ago she was dying of cancer.

Kashaun Lawhown, 7, was facing the same fate.

Both of them were battling leukemia, and traditional treatments -chemotherapy and radiation — weren’t working.

A game changing experimental cancer treatment that utilizes the body’s own immune system gave them a second chance.

“The immune system has developed over may, many, many, you know, over millions and billions of years to actually get rid of things that don’t belong in the body. Cancer doesn’t belong there,” Dr. Stephan Grupp explained.

Dr. Grupp is the Director of Immunotherapy at The Children’s Hospital of Philadelphia where Kashaun and Emma took part in a clinical trial for this revolutionary treatment.

“We collect white blood cells from the patient — those include T-cells. Those T-cells then go to a specific place where they are manufactured; reprogrammed to actually be able to attack cancer cells,” Dr. Grupp said.

These souped-up cells, now called CAR-T cells are then put back in the body where they multiply and get to work, explained Dr. Shannon Maude.

“When they find something that they recognize, like the B-cell leukemia, they kill that off,” Dr. Maude said.

“If you had told me five years ago, how effective they would be, I wouldn’t have believed you,” Dr. Stephen Hunger said.

Better yet, some of the CAR T-Cells may actually stick around to fight a recurrence, Dr. Hunger explained.

“A one-time treatment can certainly lead to at least five years of survival, and we hope can lead to cures,” Dr. Hunger said.

After battling leukemia for five years, it took just one T-cell treatment to finally put Kashaun’s cancer into remission.

“Everything worked out good and I’m healthy,” Emma added.

Just four days after her treatment there was no sign of her cancer. What’s more amazing, she’s been in remission now for 18 months.

“Out of many, many years, or many, many people doing a lot of work to come to this point, it’s really exciting,” Dr. Maude said.

The CAR-T therapy is effective mainly against leukemia and lymphoma but researchers are working to also use it against so-called solid tumors like breast, colon, and lung.

Not all patients have their cancer destroyed, the trials have been positive enough that the FDA is expected to approve the therapy this year.