10/28/2015 16:30 EDT | Updated 10/28/2016 01:12 EDT

Rob Ford has tumour growing on bladder, unsure if it is cancerous

TORONTO — Former Toronto mayor Rob Ford says he has a tumour growing on his bladder.

The city councillor says he was experiencing abdominal pain and recently underwent testing at Mount Sinai Hospital in Toronto.

Ford, who was diagnosed with a rare type of cancer in September 2014, says he's awaiting test results to determine if the tumour is cancerous.

He says he has been undergoing treatment for the new tumour.

Ford had a cancerous tumour removed from his abdomen in May and last month said he was cancer free.

Ford was campaigning for re-election when he was first diagnosed with cancer last September.

He abandoned his mayoralty bid and successfully ran for a council seat instead.

Ford underwent surgery in May following several rounds of chemotherapy and radiation.

He sent a tweet Wednesday afternoon thanking his supporters for their "continued thoughts and prayers."

"I remain optimistic that I will be able to overcome this setback," he said. 

The Canadian Press