The two boys in a sixth floor room at Boston Children’s Hospital – 4-year-old Zachary in bed playing a bike race game on an iPad and 2-year-old Gabriel asleep on his mother’s shoulder – are recovering from stem cell transplants for a pre-leukemia condition so rare in pediatrics that only 50 other cases have been reported globally. The brothers are among the seven children that Dr. Inga Hofmann has treated for myelofibrosis, a blood disorder that usually strikes older adults. This is why the Kaiser boys and their family moved here in February 2015 from Ohio to be treated at the Dana-Farber/Boston Children’s Cancer and Blood Disorders Center.
“Myelofibrosis is rare even in adults, but it is much more common in adults than in children,” Hofmann says. “Very little is known about children with the condition. The concern has always been that it could lead to bone marrow failure or leukemia.”
The Kaisers’ saga began at Zachary’s 2-year-old check-up in July 2013. A routine hemoglobin check showed low blood cell levels, and Zachary was hospitalized in Columbus for a week. His mother, Candice Kaiser, was nine months pregnant with Gabriel at the time.
Preliminary results of a bone marrow biopsy raised concern that Zachary might have leukemia, but that was quickly ruled out. After a year of testing, doctors finally reached a diagnosis: myelofibrosis. Zachary began a course of transfusions to control the bone marrow disorder, which causes scarring of the marrow because the disease disrupts the body’s production of blood cells.
Gabriel is diagnosed with myelofibrosis
When Gabriel was 10 months old, Candice took him to the pediatrician for a suspected ear infection. A nurse noticed the baby looked pale, and, given Zachary’s history, the doctor ordered a complete blood count, which showed a low hemoglobin level. A bone marrow biopsy revealed that Gabriel also had myelofibrosis. Soon Gabriel was getting transfusions, too.
Zachary responded to steroid treatment, but he couldn’t stay on it long-term because it would mask any leukemia that might develop. Gabriel’s bloodwork indicated he might be on the verge of developing leukemia, so he was never a candidate for steroids.
The boys’ doctor at Nationwide Children’s Hospital in Columbus contacted Hofmann. “She said, ‘I have these two interesting patients,’” Hofmann recalls.
From Ohio to Boston
Soon those interesting patients, their parents and two older siblings were in Boston, settling into temporary housing in the city’s West End.
“This disease is so rare in children it’s hard to find an expert, but if there is one, then it’s Dr. Hofmann,” says Dan Kaiser, the boys’ father. “This is a progressive disease. The longer you wait, the harder it is to treat.”
“We were leaning toward coming here anyway,” adds Candice. “Dana-Farber/Boston Children’s is the #1 hospital for pediatric cancer.”
On March 4, Gabriel, who loves trucks and tractors, underwent a stem cell transplant, using an unrelated donor. Zachary, builder and wrecker of Lego structures, had his stem cell transplant on July 17, again with an unrelated donor.
Along the way, the Kaisers rented their home in Ohio, became Red Sox Fans and took in a few games at Fenway Park. Dan Kaiser, a service company manager who says his “fantasy baseball team has always been whoever can beat the Yankees,” arranged to telecommute. The couple home schools their children.
The boys are back with their family now, in isolation in a newly rented house in southeastern Massachusetts, while their bodies accept the new cells and reconstitute their immune systems. One recent morning, they and their brother and sister and parents arrived at Dana-Farber’s outpatient Jimmy Fund Clinic for their weekly check-up.
All six wore matching green and blue shirts that say “I’m rockin’ green for someone special” on front and “We got your back, Gabe and Zach” on the back. There’s a prayer, too, from the prophet Jeremiah: “For I know the plans I have for you, says the Lord. They are plans for good and not for disaster, to give you a future and a hope.”
Meanwhile a mutation associated with myelofibrosis in adults was reported last year in the New England Journal of Medicine, but there is no evidence of the mutation in children. Even though the pediatric version often appears to be an inherited disorder, Hofmann found no common genetic abnormality in sequencing she performed on the Kaiser brothers and the rest of the family – and no common genetic abnormalities in any of her other patients, including siblings from the United Arab Emirates.
“If we find other families with pediatric myelofibrosis,” Hofmann says, “maybe we can figure it out.”