Meet Ava’s Physician, William Slayton, M.D.

Dr. William Slayton, fondly known as “Dr. Bill,” insists he doesn’t do “owies.” To gain the trust of the already shaken hearts of his pediatric patients, he immediately tries to relieve any fear that he will hurt them.

Serving as the division chief and program director of pediatric hematology/oncology since 2002, he has developed his own tricks to crack a smile on even the weariest of faces. “So, are you married?” he notoriously asks the 8-year-olds.

For 11-year-old Ava Mason, it was “Are you still dating Justin Bieber?”

By the time the Mason family found their way to UF Health Shands Children’s Hospital three years ago, they were exhausted from leaving hospitals with inconclusive results and doses of steroids that subsequently altered Ava’s treatment and rate of diagnosis. It was at UF Health that the family finally found the answer to their questions—and the news that no parent wants to hear. Ava had leukemia/lymphoma.

At the time, Slayton, a member of the Children’s Oncology Group (COG), was involved in a discussion regarding a subset of T-cell lymphoma patients with markers on their lymphoma cells that differed from the standard. When he returned to Gainesville to look at Ava’s original biopsy, he found some of those same markers he was studying, and he was able to consult with T-cell lymphoma experts from COG. Through their collaboration, they found that Ava actually had a rare form of acute leukemia of ambiguous lineage.

“At this point, I think the family wanted to be assured she was getting the right therapy for this type of leukemia,” Slayton said. “Because of COG, we had access to people at the cutting edge of childhood cancer treatment. We were able to get them to look over Ava’s biopsy results and make a final statement about what she has.”

To have access to those doctors from all over the country, who readily provide their expert opinion, was invaluable in treating Ava’s once mysterious case, he said.

Slayton is currently leading a trial with COG, focused on patients with Philadelphia Positive Chromosome Leukemia and developing a new drug called dasatinib that has received the same positive results as patients who have undergone bone marrow transplants. His study was presented at the International Society of Pediatric Oncology and won its Clinical Trial Research Award.

“There is a high potential to improve the outcomes of these patients,” Slayton said, “patients who are kids who otherwise wouldn’t survive, but are now surviving into adulthood and having families of their own.” It is his hope that these patients will have outcomes similar to Ava’s, who is now three months out of therapy and has no physical limitations.

Today, Slayton and the Mason family remain in touch, and Ava attends Camp Boggy Creek, where Slayton and is wife, Marci, are camp physicians. She will continue to have checkups once a month for the next year to monitor her progress.

For the first time in three years, she is back in school. She plays her heart out at recess and bears the smile of any happy, healthy 11-year old. And while she might not be able to tell Slayton she is dating Justin Bieber, she did get a chance to meet him through the Make a Wish Foundation.