Story highlights Toronto hospital executive: A CT scan shows Rob Ford has a tumor in his abdomen

It's not known if the tumor is malignant or how it will be treated, the executive adds

Rob Ford is "in good spirits," his brother says

The mayor, who is running for re-election, has been dogged by his substance abuse

Toronto Mayor Rob Ford now has a new fight on his hands: a tumor.

The president of Humber River Hospital announced Wednesday that the embattled mayor -- just over two months removed from treatment for substance abuse -- has been admitted to the hospital, where doctors will try to get "a definitive diagnosis."

"It is being investigated further and we need to determine exactly what type of tumor it is, and then we can decide on what type of treatment is required," said Dr. Rueben Devlin, the Toronto hospital's president.

According to Devlin, Ford has been "complaining of abdominal pains" for over three months that got worse over the last 24 hours. That prompted the mayor to go the hospital, where a CT scan revealed the tumor in his abdomen.

It's not known yet if the tumor is malignant, according to Devlin.

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Doug Ford, the mayor's brother and a Toronto city councilor, asked reporters "just to give our family a day or so" as they learn more about the situation and determine what to do next -- including deciding whether or not Rob Ford will continue his campaign for re-election.

"Rob is in good spirits, and I just want to thank the well-wishers for all the calls that are coming in," Doug Ford said.

The health ailment adds to the list of struggles facing Ford, whose fall from grace began in May 2013 with the release of a cell phone video that appeared to show him smoking crack cocaine. The Toronto city council largely stripped him of his mayoral powers months later over those and other allegations of bad behavior.

Ford didn't back down, though, instead vowing "outright war" on the city council.

The mayor apologized for "a lot of stupid things," including having used crack cocaine, but he refused to resign or enter rehab. In fact, despite all the criticism and his becoming a punchline for jokes in Canada as well as the United States, Ford launched a bid for re-election.

Yet this past spring, after a local newspaper reported on a new video that allegedly shows him smoking crack cocaine, Ford relented on one front: by going into rehab.

He returned to work in late June, after a two-month rehab stint, saying he was "ashamed, embarrassed and humiliated" by some of his past actions.

But even then, he refused to resign or refrain from campaigning, saying to the voters of Toronto, "I look forward to serving you for many, many more years."