A fighting Chance: Baby Chance Popp beats leukemia, thanks to bone-marrow transplant from big sister

It was just supposed to be a name that Amber Popp and her husband, Cory, could agree on.

"We definitely didn't realize when we picked it out, how perfect it was," she said.

Baby Chance, however, earned his name both by being diagnosed with a rare form of leukemia and by beating it.

Chance, who was 18 months old yesterday, was born with Noonan syndrome -- a physical and developmental condition -- after what Amber said was a normal pregnancy and delivery. Amber, who lives in Benton, Missouri, remembers the doctors noticing a couple features that suggested Noonan syndrome, but she said she didn't think anything of it.

"His eyes were kind of wide spaced, but I just assumed it was due to stretching from birth," she said. "The genetic testing that they did came back normal."

Eighteen-month-old Chance Popp snuggles with his mother, Amber, and sister, Layla, 9, on the couch in their apartment at the Ronald McDonald House in St. Louis Tuesday morning.Laura Simon

But that was just because doctors don't typically test for Noonan syndrome. It's too uncommon; only one in 1,000 to 2,500 babies are born with it. Amber and Cory were shocked to find out Chance had a condition that causes a number of severe side effects.

"It was quite a surprise because the girls never even had an ear infection," Amber said, referring to the couple's other two children, Natalie, 11, and Layla, 9. "You kind of take for granted having a healthy kid."

But Chance's condition meant heart surgery and other complications. He's profoundly deaf, and the near-constant hospitalization often upsets him, causing nurses to call him the "grumpy old man baby" of the children's ward.

"Life does that," Amber said. "You make your plans and then life does what it's going to do. ... After Chance was 9 months old, it's just been a whirlwind."

His diagnosis of Noonan syndrome was jarring for the family at first, but turned out to be a blessing. Children with Chance's condition are at a higher risk for juvenile myelomonocytic leukemia, blood cancer that typically affects children younger than 4. If doctors hadn't spotted the Noonan syndrome, they might not have found the cancer as early as they did.

"We were pretty lucky that they noticed it," Amber said.

But the treatment, incredibly, was initially to wait for it to go away, she said. JMML typically resolves itself in patients with Noonan syndrome.

Chance wasn't getting better, though. Doctors performed surgery to remove his spleen, and a biopsy of his liver revealed acute lymphoblastic leukemia, another form of cancer.

"[Having both JMML and ALL] is pretty much unheard of," Amber said. "You're not going to find a lot of research on people who have both."

Chance needed a bone-marrow transplant, and the doctors discovered his sister Layla was "a 10 of 10 matchup." Since transplants from siblings have a higher rate of success, she was an appealing prospective donor, and eager to help.

"At this point, since we'd been dealing with it since he was 9 months old, we just roll with the punches, like, 'This is what we have to do now,'" Amber said. "Layla was really happy that she was the donor. She's a really brave little girl. Very proud."

Now, nearly all of Chance's bone marrow cells are Layla's, and even his blood type changed to match hers. But the cancer is gone. The family has to stay close to the hospital in St. Louis until next month, and Chance may have to be on immunosuppressants for a time, but things are looking up.

"I don't want to jinx myself," Amber said. "But beating leukemia is huge, and I hope it will be happy sailing going forward."

tgraef@semissourian.com

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