Fedoruk, who was the first female lieutenant-governor in Saskatchewan, died Wednesday night. The provincial government gave no immediate cause of death, but said Fedoruk had recently suffered a fall.
She was 85.
"It's a sad day for Saskatchewan," said Premier Brad Wall.
"Here was a citizen of our province who was a leader in every respect. Obviously, academically, she was a pioneer."
Fedoruk was the chief medical physicist for the Saskatchewan Cancer Foundation. She was one of four scientists to develop one of the first nuclear scanning machines and the cobalt 60 therapy unit in 1951.
"That was really what pioneered the treatment of cancer, using high intensity radioactive cobalt in humans. That was her big claim to fame," Canadian Medical Hall of Fame executive director Janet Tufts said in a phone interview from London, Ont.
"But she was one of Canada's foremost medical-biophysicists and the only woman who, in the 1950s, was conducting medical physics research in Canada."
Tufts said cobalt radiation became the standard of radiation therapists worldwide. It was estimated that by the end of the century it helped more than 70 million people with their cancer treatment.
The hall's website says Fedoruk also contributed to the development of the Dosimeter, which allowed doctors to control the amount of radiation each cancer patient received. She also participated in the development of one of the first whole body scanning machines that used radioactive nuclides to help detect cancers of the thyroid and liver.
"She really was doing groundbreaking things that no women were doing in her time," added Tufts.
Fedoruk was the first woman member of the Atomic Energy Control Board of Canada.
When she was a student at the University of Saskatchewan, she was also a member of 12 intervarsity championship teams.
She went on to become the first female chancellor at the University of Saskatchewan, holding the post from 1986 to 1989. She served as lieutenant-governor from 1988 to 1994. Fedoruk was also an accomplished athlete and her name was added to the Canadian Curling Hall of Fame in 1986.
She was appointed an Officer of the Order of Canada, awarded the Saskatchewan Order of Merit and received the Queen's Silver Jubilee Medal.
Former Saskatchewan premier Roy Romanow said Thursday that Fedoruk meant a lot to him.
"She was an invaluable adviser, a real solid rock of an individual, a person with a big heart, a tremendous contributor to science, with respect to nuclear medicine and academic work," said Romanow.
"I'm so pleased to have known her."
Romanow called Fedoruk's death is a "huge loss" for Saskatchewan and for all Canadians.
Wall said Fedoruk was very down to earth, someone who was as comfortable talking about curling as nuclear medicine.
He called her a trailblazer and said her impact on the province was extraordinary.
"How many people, who at their passing, can have that said of them that they literally didn't just change lives but they saved many. She was just sort of the epitome of what is good about the province of Saskatchewan," said Wall.
— With files from CJWW
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