The Connecticut Supreme Court is set to hear a case on Thursday regarding a 17-year-old girl who is being forced against her will by the state to receive chemotherapy treatment for cancer.

The teen, identified as Cassandra C., was diagnosed with Hodgkin lymphoma last September. However, her mother supports her decision not to undergo chemo, despite the fact that doctors say she has an 80 to 85 percent chance of survival with the treatment. Without treatment, medical experts say that they are almost certain that she will die within two years, reports the Associated Press.

After Cassandra and her mother missed several doctor appointments last year, medical workers at the hospital notified the state Department of Children and Families (DCF), which investigated the case. A trial court then granted the state agency temporary custody of Cassandra and forced her to undergo what they called life-saving chemotherapy. As a result, doctors surgerically installed a port in her chest in order to administer chemotherapy chemicals when her treatment resumed on Dec. 17.

Lawyers representing Cassandra and her mother say the teen should have the right to deny medical treatment as a mature minor who will turn 18 in September. They filed an emergency appeal on their clients' behalf, asking the state's high court to decide whether some minors are mature enough to make decisions about their own bodies.

"Give us the chance to prove that she has the maturity to do this," Assistant Public Defender Joshua Michtom, Cassandra's attorney, said. "One has a right to bodily integrity. It doesn't matter if it's harmful. An adult's right to refuse care is without limitation, provided they're not incompetent."

Michtom added that this case will be the first time the state Supreme Court will consider the "mature minor doctrine," which generally allows court hearings for minors at 16 and 17 years old to prove that they are mature enough to make their own medical decisions.

The DCF defended their treatment of Cassandra, however.

"When experts, such as the several physicians involved in this case, tell us with certainty that a child will die as a result of leaving a decision up to a parent, then the department has a responsibility to take action," they said in a statement on Monday.

The child protection agency also argues that seeking and winning temporary custody of Cassandra was required "[e]ven if the decision might result in criticism; we have an obligation to protect the life of the child when there is consensus among the medical experts," according to the Hartford Courant.

Jackie Fortin of Windsor Locks, Cassandra's mother, told WVIT-TV in a recent interview that her daughter "has always -- even years ago -- said that if ever she had cancer ... she would not put poison into her body."

Fortin said that the decision was not motivated by a religious belief; instead Cassandra looks at chemotherapy as "poison."

"My daughter is refusing chemo because of the poison toxins that she does not want in her body. She knows the long term effects of having chemo, what it does to your organs, what it does to your body," Fortin said during an interview published by the Courant. "It not only kills cancer, it kills everything in your body, she knows this. This is her human rights, her human constitutional rights not to put poison in her body."

Cassandra is currently being held at Connecticut Children's Medical Center in Hartford.