ABC News November 28, 2013

Gap in Chemo Makes Amish Girl's Leukemia More Difficult to Treat, Say Doctors

WATCH: Sick Amish Girl, Family Seek Treatment Outside US

A 10-year-old Amish girl whose family stopped chemotherapy treatments for her leukemia faces severe health risks even if she restarts treatment, according to doctors.

Sarah Hershberger and her family fled their home in northeast Ohio days before a state appeals court appointed a guardian to take over medical decisions for Sarah's parents.

The family has left the country to find alternative treatments and has no plans to return to Ohio anytime soon, according to the family's lawyer, Maurice Thompson.

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"It's the constitutional right, but [there's a] moral right to refuse conventional medical treatment," Thompson told ABC News Wednesday.

Sarah was diagnosed last April with stage III lymphoblastic lymphoma, which is the most common type of leukemia found in children. According to court documents, the cancer produced tumors in Sarah's neck, chest and kidneys.

Although Sarah was initially treated with chemotherapy, her parents abruptly stopped treatment in June after the drugs made their daughter sick and she begged her parents to take her off the treatment.

Doctors said that by stopping the chemotherapy even temporarily, Sarah's leukemia could become even more difficult to treat.

Dr. Howard Weinstein, chief of pediatric hematology oncology at the Massachusetts General Hospital for Children in Boston, said the gap in treatment would likely mean that Sarah would need a more intense round of chemo if she resumed treatment.

"We don't want any gap, because the leukemia cells can multiply and become resistant to chemotherapy," said Weinstein

Weinstein explained that stopping Sarah's chemo for just a few months was long enough that if she returned for chemotherapy, "it would be pretty much starting again, but not with the same likelihood of cure. But definitely with a reasonable chance."

After the Hershbergers stopped chemotherapy for Sarah, they said they planned to treat her with unconventional and "natural" medications instead.

"We've seen how sick it makes her," Andy Hershberger told ABC News last August. "Our belief is the natural stuff will do just as much as that stuff if it's God's will. She would have more suffering doing chemo than not."

Weinstein said for many parents the first few months of chemotherapy could be very difficult as they watch their children becoming sick from the drugs.

"Both parents and children sometime think the therapy is worse than the disease if they were not terribly symptomatic when diagnosed," said Weinstein. "But the majority of families realize in order to cure the leukemia you have to go through difficulties."

Weinstein said many pediatric leukemia patients can "appear" to be cured after one month of chemotherapy but said previous studies had found that the leukemia would return if the treatment was not extended, because the cancerous cells can "hide" in the body.

Weinstein warned that if people quit chemotherapy early and switched to natural remedies, they might believe the new treatments were working.

"If you're taking natural, nonconventional therapy you might say, 'Oh my god it's working,'" said Weinstein. "But really, the first month of chemotherapy did all the work."

Weinstein said that without conventional long-term treatment, the type of leukemia that Sarah had would virtually always return in pediatric patients.

The Hershberger family was initially taken to court by the Akron Children's Hospital after it stopped chemotherapy treatment in June.

In October, an Ohio appeals court granted an attorney, who's also a registered nurse, limited guardianship over Sarah and the power to make medical decisions for her.

The court said the beliefs and convictions of her parents couldn't outweigh the rights of the state to protect the child.

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ABC News' Anthony Castellano and Alex Perez contributed to this report.