Five-year-old Jocelyn Dickhoff, who loves books and baby dolls, has only a slim chance of surviving the rare and aggressive muscular cancer she's spent most of her life battling.

Whether she'd be healthy today if the cancer had been discovered sooner is at the heart of a Minnesota Court of Appeals ruling that permits her family to sue the doctor who failed to make an early diagnosis.

The ruling also points to a peculiarity of state law -- the legality of medical malpractice lawsuits in Minnesota is linked to the patient's chances of survival.

Under Minnesota law, medical malpractice claims resulting from misdiagnosis require that the patient's odds of survival drop from likely to unlikely. For instance, if a misdiagnosis lowers a patient's chances from 70 to 60 percent, it's not a cause for action. In contrast, other states allow lawsuits for the loss of "chances."

In Jocelyn's case, experts hired by her family say the yearlong delay in diagnosing her cancer reduced her chances of survival from 60 to 40 percent, or below the threshold of likely survival.

Her chances of survival now are 5 percent, her mother said.

The unanimous appellate opinion filed Tuesday reverses a Kandiyohi County judge's earlier order that tossed out the suit filed by Jocelyn's parents, Kayla and Joseph Dickhoff of Belgrade, Minn., against Dr. Rachel Tollefsrud and Family Practice Medical Center of Willmar, Minn. The lower court judge reasoned that the Dickhoffs were making a "reduced-chance" medical malpractice claim, the kind not recognized in Minnesota.

The Appeals Court determined that Jocelyn would have been more likely to survive had it not been for the doctor's alleged negligence, and permitted the family's lawsuit to proceed.

William Hart, an attorney for Tollefsrud and Family Practice Medical Center, said they are considering petitioning the Minnesota Supreme Court to hear the case but haven't made a final decision.

"This case involves tragic, tragic circumstances, but it also involves an extremely aggressive, rare and naturally occurring disease," Hart said. "We are disappointed in the outcome because no previous Minnesota decision has allowed a case to proceed without evidence that a person's advanced disease probably occurred as a result of physician error, as opposed to the natural progression of the disease itself."

'Improbable survival'

Kayla Dickhoff said she was relieved the case will continue. She believes her daughter could have had a long life if her cancer had been caught and treated in time.

"I don't see how anybody can look at this case and not think that if she would have been diagnosed in a timely fashion, that her chances of survival would have been higher," she said. "It's a no-brainer with childhood cancer."

According to the American Cancer Society, childhood cancers represent less than 1 percent of all new cancer diagnoses. Cancer is diagnosed in about 11,000 U.S. children annually. About 1,300 die.

The Dickhoffs' attorney, Stephen Rathke, considers the reversal "what most people understood the law to be.

"I don't think the opinion broke any new ground so much as it clarified the parameters of a lawsuit involving a very sick person," Rathke said.

The Dickhoffs sued the doctor and medical center in 2009, alleging Tollefsrud had failed to diagnose as cancer a bump that grew on Jocelyn for a year after her birth in 2006.

In 2007, when she was a year old, a pediatric oncologist diagnosed the bump as stage IV alveolar rhabdomyosarcoma (RMS) -- a rare childhood muscular cancer that had already spread to other parts of her body.

According to the ruling, RMS is diagnosed in about 350 children annually, and children in their first year generally have a worse prognosis than others. The past four years of Jocelyn's life have been a cycle of radiation, chemotherapy and surgeries, her mother said.

The case was scheduled for trial in 2010 but was repeatedly delayed because of the recurrence of Jocelyn's cancer.

Tollefsrud and Family Practice moved to throw out the suit, arguing that the malpractice claim was for "reduced chance of life" because the allegations refer to a "shortened life expectancy" and "deprivation of normal life expectancy."

District Judge Donald Spilseth dismissed the family's suit, arguing that claims for "reduced chance of life" have been consistently rejected by the Minnesota Supreme Court and that expert testimony did not prove the doctor's alleged negligence, rather than the cancer itself, caused the toddler's condition.

In the 13-page Appeals Court order, Judge Kevin Ross reasoned that because Jocelyn's chances of survival are so low, the case involves "improbable survival" -- which is permissible in Minnesota -- rather than a "reduced chance" of survival.

"We believe that the Supreme Court did not intend to completely foreclose the possibility of malpractice actions for negligent cancer-misdiagnosis cases involving a lengthy illness with a potentially fatal outcome," he wrote.

Additionally, he said testimony by the Dickhoffs' experts showed it was possible a jury could find the recurrence of the child's cancer was caused by the doctor's negligence.

If a scan scheduled for Thursday reveals that Jocelyn's cancer is continuing to spread, "there's not much they can do for her," Kayla Dickhoff said.

In the meantime, the little girl continues to play with her dolls and her little brothers.

"Looking at her, you wouldn't know she's sick," her mother said. "She's got her hair, she runs around and goes to school. She's got a really big attitude."

Abby Simons • 612-673-4921