Amazing Procedure By Sloan Kettering Doctor Saves Leg Of Young Boy With Aggressive Bone Cancer

NEW YORK (CBSNewYork) -- A local mom and dad recently faced an agonizing decision.

In order to save their son, his leg needed to be amputated.

But as CBS2's Dr. Max Gomez found out, an amazing procedure saved young Zachery Levine's leg.

It started with bone cancer growing in Zachery's thigh bone. Treatment for that is usually leg amputation and chemotherapy. It would save his life, but at a huge cost.

Then the family found a doctor at Memorial Sloan Kettering Cancer Center who offered a way to save the young boy's leg.

"I can hear the doctor even now saying he had a particularly nasty kind of tumor. Those are exactly the words that he used," mother Capron Levine said.

The tumor was an aggressive osteosarcoma growing and destroying the lower part of his thigh bone. Treatment usually includes amputation.

"Trying to tell a 5- or 6-year-old that you can't do any of the things that other kids can do was a burden we weren't sure how to put on a 5-year-old," Capron said.

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But the Levines were referred to Dr. Daniel Prince at Sloan Kettering, who said, "We can avoid amputation in the majority of people. We try what's called 'limb salvage.'"

The first step is surgery removing the length of cancerous bone, leaving a six-inch gap in Zachery's thigh bone. He also had to go through six rounds of chemotherapy to kill off any remaining cancer.

But the amazing part was how Dr. Prince would induce Zachery, himself, to regenerate the missing length of bone.

It's called "bone transport." Cuts are made in his remaining upper thigh bone, pins are inserted and then every day his parents would turn a crank to stretch that bone one millimeter at a time. The same process that heals a broken bone slowly makes new bone in the gap until it meets the remaining thigh bone right above the knee.

"It all looks exactly like normal bone," Dr. Prince said.

That bone stretching meant Zachery had a metal cage around his leg with pins inserted in his thigh for six months.

Now, more than two years later, Zachery, now 8, is cancer free and walking in the Sloan Kettering "Walk for Kids." He's using crutches for a little extra security in the crowd. It's just an amazing recovery.

It is a gift. It's more than we thought was possible," Capron said.

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Prince said limb salvage isn't always possible, but along with chemo it is saving lives and legs for the many children with bone cancer.

Zachery told Gomez that he wants to be an inventor one day and build a time machine, so he can bring back a dinosaur as a pet.