The tumour in Rob Ford's abdomen, the discovery of which led the mayor of Toronto to drop out of the election last week, is both malignant and rare, according to medical authorities.

Dr. Zane Cohen of Mount Sinai Hospital's surgical team addressed the media today in Toronto to provide an update on Ford's medical condition, which, he noted, was done due to great public interest.

He said a repeat biopsy was done Monday on "the mass," meaning the abdominal tumour.

"The diagnosis is a malignant liposarcoma," said Cohen, which is a form of cancer that arises in fat cells in deep soft tissue; it is, Cohen said, a rare and difficult tumour to treat.

"It has about 60 different cell types and that's what makes it a very rare tumour and a very difficult tumour," he said.

"We have not found cancer" in Ford's organs, Cohen noted, later adding that the tumour appears "very aggressive" based on its size after its recent discovery and that it has been growing since well before that, but Cohen added that the treatment plan is also aggressive, involving an initial three days of chemotherapy, a rest day and an 18-day "washout period" before possible subsequent 40-day cycles over the treatment plan, which Cohen said is to begin within the next 48 hours.

The Canadian Press reports :

"Following the chemotherapy and its results, doctors may or may not decide to carry out surgery or radiation treatments."

"Everyone knows chemotherapy is tough ... he [Ford] is a pretty strong person, but he's going to have some tough days," said Cohen, an internationally recognized colorectal surgeon. He added that Ford will also have some good days, and that "doctors will decide what the next step will be based on how the tumour responds to treatment."

The Ford family, along with everyone following the Toronto mayoral election and the general Ford saga, had been awaiting the results of last week's biopsy.

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The nature of the "fair-sized" tumour -- about 12 cm by 12 cm, according to Cohen on Wednesday -- and specifically whether it is cancerous, became the subject of much speculation and curiosity leading up to today's medical announcement.

Members of the family, including the mayor's wife, Renata, his brother Randy and his nephew Mike attended the hospital ahead of the announcement, but did not speak with the media.

"Our family's strong, Rob's strong and with all the support of the people, that's what keeps us going,"said his brother, Coun. Doug Ford on Tuesday.

Following the diagnosis Wednesday, Doug Ford issued a brief statement:

"Rob will beat this," said Doug Ford.

"He is an incredible person, husband, father, brother and son and he remains upbeat and determined to fight this."

"Rob has always been so strong for all of us and now I ask us all to be strong for him."

On Friday, Doug Ford announced his candidacy for mayor, and that he was replacing his brother on the ballot for mayor; Ford is now running for city council in Ward 2, a position he held for 10 years before he was elected mayor in 2010.

That switch, withdrawing Rob's name off the ballot for mayor and adding Doug's (and the switch to a councillor nomination for Rob) took place on the afternoon of Friday, Sept. 12, at the last possible moment before the city's election registration closed, leading to great speculation on what may have happened or may be happening behind the scenes in the Ford campaign.

Mayoral opponents John Tory and Olivia Chow, now considered the main competitors for Doug Ford, who has yet to start his mayoral campaign in earnest, responded to the news on Wednesday with supportive messages wishing Ford a successful recovery.

Chow's words, coming from a politician and public figure whose late husband, former federal NDP Leader Jack Layton, passed away from cancer in 2011, carry a special resonance in this moment.

"I know what it's like when a family receive bad news, but I also know the strength that the support and the warm wishes can give to you," she said. "I know Rob Ford is strong. He's a fighter … I hope he can win this battle against cancer."

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