His brother, Doug Ford, says the city councillor was admitted to Mount Sinai Hospital at the end of February for another scheduled round of chemotherapy.
Ford was diagnosed with a soft tissue cancer known as pleomorphic liposarcoma in September 2014.
Following an aggressive round of treatment, Ford underwent surgery to remove the tumour last May.
In October, he suffered a setback when it was discovered that he had two cancerous growths on his bladder.
Doug Ford says he’s uncertain how long his brother will be in hospital this time. He says the former mayor appreciates all the calls of support he’s been getting and he's "always staying positive.”