Mayor Rob Ford (GEOFF ROBINS/AFP/Getty Images)

This announcement comes after Ford was hospitalized and the tumor was discovered. Biopsy results are not in yet. 

Ford was running for re-election despite drug and alcohol scandals. His brother, Doug Ford, will run in his place. 

Instead, Ford is seeking a spot on City Council. 

Ford gained attention in 2013 when the media reported on the existence of a video apparently showing Ford smoking a crack pipe. 

More reports surfaced and Ford decided to enter rehab, according to CBS News. He returned to work in June. 

Read more at CBS News. 

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