Former Toronto Mayor Rob Ford's Rare Abdominal Cancer, Explained

Rob Ford, the controversial former Toronto mayor who was known both for smoking crack cocaine in office and his intense popularity among conservative working-class voters, died today  at the age of 46. The cause of death was not announced, but Ford was being treated for rare abdominal cancer called pleomorphic liposarcoma -- a diagnosis he received in 2014. 

"It's rare to have a highly successful outcome with a pleomorphic liposarcoma once it's spread," Dr. Brian Van Tine, a medical oncologist at Washington University in St. Louis, told the Canadian Press. 

Liposarcomas belong to a class of tumors that begin in the body's connective tissue and resemble fat cells. They are relatively uncommon, only affecting about 2,000 people per year in the United States, according to Memorial Sloan Kettering Cancer Center. (In comparison, about 225,000 cases of lung cancer are diagnosed in the U.S. each year.) Pleomorphic liposarcoma is considered the rarest subtype and is extremely aggressive, with five-year survival rates of only 56 percent , according to the Liddy Shriver Sarcoma Initiative. 

Liposarcoma is often asymptomatic , but patients sometimes experience a new or persistent lump on the body, which can be painful or numb. Others report abdominal pain, cramping, bloody stools or bloody vomit. To diagnose liposarcoma, many doctors recommend a biopsy of the suspicious tissue.

At the time of his diagnosis, Ford had a malignant tumor measuring about 5 square inches in his abdomen , and a second tumor measuring less than an inch in his buttocks. He underwent surgery, radiation and chemotherapy, and after doctors found two new tumors on his bladder the following year, Ford resumed chemotherapy last fall.

It's not clear what causes liposarcoma or what the risk factors for the disease might be, though there is some preliminary evidence that certain inherited diseases, exposure to particular chemicals, a suppressed immune system, or radiation therapy from previous cancer treatment could play a roll. 

"There’s no data I’m aware of that links liposarcomas to alcohol , tobacco, anything,” Dr. Howard Bailey, a professor of medicine at the University of Wisconsin, told the Toronto Star in 2014, ostensibly refuting any rumors that the cancer was caused by Ford's notorious lifestyle. 

Ford withdrew from his mayoral re-election campaign in 2014 to start cancer treatment, then changed tracks and ran a successful campaign for a seat on Toronto's city council the same year. Ford's brother Doug, who entered the mayoral race in his place, lost the election.