Last year Cassandra Callender, then 17, underwent five months of forced chemotherapy treatment for her Hodgkin’s lymphoma after Connecticut’s Department of Children and Families decided to intervene.

Her doctors had told her that chemotherapy was her best chance of survival, but she still refused, hoping to find alternative treatments.

The case eventually ended up in the state’s Supreme Court. The court found that the Department of Children and Families had not violated Callender’s rights by requiring her to undergo chemotherapy.

The ruling gave some finality to that case.

But it did little to clear away disagreements about when it is OK to force a teenager—especially one so close to being an adult—to undergo a treatment she or her parents didn’t agree with.

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Best Interests of a Child

Most of the time, children and their parents agree with doctors’ recommendations for cancer treatment. But that’s not always the case.

“We have encountered concerns about toxicity. We have encountered preferences for complementary therapies, aside from traditional cancer medicine,” Dr. Jennifer Kesselheim, M.Ed., a pediatric oncologist at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center, said in an interview with Healthline.

“We’ve also encountered individuals who, for religious or cultural reasons, prefer to do something other than what the clinical team recommends.”

If the parents and child disagree with the proposed treatment plan, doctors will generally listen to the parents’ wishes.

“If the parent believes that a treatment should move forward, then we will agree with the parents, because we feel like the parents have the child’s best interests at heart. And we feel like the parents are still the decision makers until the child turns 18,” Dr. Tracy Koogler, a critical care pediatrician and medical ethicist at the University of Chicago Medicine, told Healthline.

While doctors have children’s medical best interests in mind, families can provide a sense of broader best interests.

How will a treatment impact a child’s quality of life? When is the best time to undergo the treatment? Does it fit with the family’s religious or cultural beliefs?

The answers to these questions can shape conversations about the best course of treatment.

“The sooner we can know about all of these different pieces that make up the fabric of the child’s life outside and leading up to this new diagnosis,” said Kesselheim, “the better that we can be prepared to meet their needs in later conversations.”

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Mature Minors

If both the child and the parents refuse treatment, the situation becomes a bit more complicated.

“When you have the parents and a children both saying ‘No,’ it becomes an interesting situation,” said Koogler.

Some of these cases hinge on whether a child is mature enough to make their own medical decisions.

Several U.S. states allow “mature minors” to consent to general medical treatment even without their parents’ approval. In some cases this also means the right to refuse treatment.

Telling whether a teenager is mature is not always easy.

“Sometimes the patient’s chronological age can help us understand what their capabilities and decisional capacities may be,” said Kesselheim. “Other times we meet patients who have capacities that far surpass or maybe fall short of what we might expect given their chronological age.”

Callender was a few months shy of her 18tht birthday when she underwent chemotherapy. The Connecticut Supreme Court, though, ruled that she was not mature enough to make her own medical decisions.

In other states, cases similar to Callender’s have had different outcomes.

In 1989, a 17-year-old teenager refused treatment for leukemia because the needed blood transfusions would go against her beliefs as a Jehovah’s Witness. Her mother sided with her.

A lower court in Illinois found that the teen was being neglected and appointed a guardian to consent to the blood transfusions for her.

However, it was later ruled that the teenager was a “mature minor” and could refuse the blood transfusions.

“If you looked at that case, you could decide that a mature minor with the agreement of his or her parents should possibly be allowed to make these decisions,” said Koogler.

However, as seen with the Callender case, that’s not always what courts decide.

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Severity of Disease

When handling a child’s refusal, doctors also take into account the severity of the disease.

Callender was diagnosed with Hodgkin’s lymphoma. There is a good survival rate for patients with this type of cancer. Her doctors had told her that with chemotherapy, and sometimes radiation, patients have an 85 percent chance of being disease-free after five years.

“It’s very difficult for a physician to look at a disease process that has an 80 to 90 [percent] cure [rate] and say ‘What do you mean, we’re not going to do what we always do?’” said Koogler.

If the benefits of treatment are less clear, doctors may be more willing to let a patient try an alternative therapy or avoid a court case when a patient refuses.

“If we think that the treatment, sadly, is unlikely to change that outcome for the patient—that it may actually cause potential harm and may not yield benefit,” said Kesselheim, “then we view that kind of refusal very differently.”