MINNEAPOLIS — A Minnesota Supreme Court decision in the case of a little girl with cancer says state law allows a patient to seek damages if a doctor’s negligence causes that patient’s chances of recovery or survival to be reduced — a significant shift in the way Minnesota has looked at malpractice claims in the past.

But dissenting judges warned that the decision overrules longstanding precedent and will unfairly hold doctors liable for harm that may never materialize.

Friday’s 3-2 ruling comes in the case of a couple who claims their daughter’s rare form of muscle cancer would have been curable if it had been diagnosed earlier. Kayla and Joseph Dickhoff sued Dr. Rachel Tolefsrud and the Family practice Medical Center in Willmar in 2009, claiming their negligence caused injuries that would lead to future expenses and pain.

The doctor and clinic have denied they were negligent. Their attorney was not in the office and did not return messages left Friday. The majority opinion, written by Justice Paul Anderson, said the “loss of chance” doctrine recognizes that a patient suffers real injury when a doctor’s negligence reduces chances of recovery or survival and a doctor “should be liable for the value of that lost chance.”