Toronto Mayor Rob Ford has been diagnosed with malignant liposarcoma, a “fairly aggressive” rare cancer, doctors treating him have said.

Rob Ford, 45, has a malignant liposarcoma in his abdomen and will begin chemotherapy within 48 hours.

“I’m optimistic about treatment,” said Dr. Zane Cohen, who is overseeing Rob Ford’s care team.

Rob Ford withdrew from his re-election campaign last week after being diagnosed with the abdominal tumor.

The controversial mayor, who admitted to smoking crack cocaine while in office, maintains a strong support base despite calls for him to resign.

Liposarcoma is a rare cancer of the soft tissue which accounts for only 1% of all cancers, Dr. Zane Cohen said at a news conference at Mount Sinai hospital in Toronto.

Rob Ford has a malignant liposarcoma in his abdomen and will begin chemotherapy within 48 hours (photo The Canadian Press)

Rob Ford has a 12cm by 12cm sized tumor in his abdomen and another smaller 2cm tumor in his left buttock, which are believed to have grown within the last three years.

“It’s a rare tumor, a very difficult tumor,” said Dr. Zane Cohen.

He also said this type of cancer had proved to be more sensitive to chemotherapy than other tumors.

Rob Ford will begin a three-day course of chemotherapy at Mount Sinai hospital within the next 48 hours, Dr. Zane Cohen said.

This will be followed by a break of 18 days, and then another course.

Rob Ford will then be scanned to see how his tumor has reacted to the treatment before doctors decide whether to administer more chemotherapy or follow up with radiotherapy or surgery.

He was admitted to hospital last week after months of abdominal pain.

The discovery of a tumor prompted him to withdraw his candidacy from the mayoral election on October 27.

Rob Ford’s brother and political confidant, Toronto Councillor Doug Ford, has replaced him on the ballot.

At the same time, Rob Ford’s name was added to the ballot papers to run for councilor in his old constituency of Ward 2 in Toronto’s Etobicoke North area, signaling his desire to remain a political force in the city.

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