A 17-year-old cancer patient and her mother are locked in an unprecedented legal battle with the Connecticut state government over the teen’s right to refuse chemotherapy treatment, Fox CT reported.

The girl, identified only as “Cassandra C." in court documents, was diagnosed with Hodgkin’s lymphoma in September. At the time, doctors at Connecticut Children’s Medical Center (CCMC) recommended she receive chemotherapy. After she refused treatment— with her mother’s support— Connecticut’s Department of Children and Families (DCF) stepped in.

According to the Hartford Courant, Cassandra believes chemotherapy can cause her as much or more damage as the cancer at this point. Hodgkin's lymphoma is a cancer of the lymphatic system. As it progresses, it compromises the body's ability to fight infection.

“She knows the long-term effects of having chemo, what it does to your organs, what it does to your body. She may not be able to have children after this because it affects everything in your body. It not only kills cancer, it kills everything in your body,” Cassandra’s mother, Jackie Fortin, said in a video published on the Hartford Courant’s website.

Cassandra was taken into temporary custody by DCF in November, and her mother was ordered to cooperate with medical care administered under the agency’s supervision, after the hospital reported her to the agency.

Cassandra underwent two chemotherapy treatments before running away from home. When she returned, she refused treatment.

The teen’s doctors testified at a trial court hearing, after which it was decided that she was to be removed from her home and remain in DCF custody— and that DCF was authorized to make medical decisions on her behalf.

Cassandra and her mother appealed the ruling and their case will be heard Thursday at the Connecticut Supreme Court in Hartford. The family claims that, by allowing DCF to use their judgment over that of Cassandra’s family, without the finding of incompetence on their behalf, the forced treatment violates the family’s constitutional rights. Additionally, they claim that the state should recognize the “mature minor doctrine” that requires that a court first determine if a minor is not adequately mature enough to be allowed to make medical decisions on her own.

“It’s a question of fundamental constitutional rights-- the right to have a say over what happens to your body-- and the right to say to the government ‘you can’t control what happens to my body,’” Cassandra’s mother’s attorney, Michael S. Taylor, told Fox CT. A public defender represents Cassandra.

According to Cassandra and her mother, Connecticut’s common law and public policy dictate that DCF cannot force the teen to receive medical treatment over her and her mother’s knowing and informed objection.

“The Supreme Court of the state has never ruled on this issue, the Supreme Court of the United States has not ruled on this issue. So it’s very significant not just for our client, and for the minor child, but for the law in general,” Taylor told the news channel.

Fortin told the Hartford Courant that even prior to her diagnosis, Cassandra would have opted not to undergo chemotherapy.

“This is her decision, and she’s very intelligent enough to make this decision on her own,” Fortin said. “She does not want poisons in her body, and she does not want to be forced through the state or the government to force her to do such a thing. And right now, at this moment, she is being forced chemo upon her against her wish.”

Side effects of chemotherapy can include nausea, hair loss, vomiting, fatigue, and diarrhea, according to the National Cancer Institute.

"Connecticut Children's is working closely with the State of Connecticut Department of Children and Families in this matter," Bob Fraleigh, spokesman for the Connecticut Children's Medical Center, said in a statement to FoxNews.com. "We are grateful that the state Supreme Court has agreed to take on this very important case and we look forward to their guidance.”

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