Former Toronto mayor Rob Ford is back in hospital undergoing more cancer treatment and taking part in a clinical trial to see if "precision medicine" can help shrink his tumours.

Doug Ford told CP24 over the weekend that his 46-year-old brother was admitted to Mount Sinai Hospital for more treatment for a rare and aggressive form of soft-tissue cancer called pleomorphic liposarcoma.

Ford underwent surgery in May, to have a large tumour removed from his abdomen, but in October, doctors found two other tumours attached to his bladder.

His brother Doug said Rob is now taking part in a clinical trial using precision chemotherapy.

Precision chemotherapy involves taking a small sample of a patient's tumour and implanting it into specialized mice that have been bred without immune systems. As the cancer grows in the mice, the lab then tests different chemotherapy drugs to see which works best on the tumours.

Ford says his brother's doctors are now waiting for the results of the mice test.

"Hopefully, in the next week, they'll be testing the mice. It takes a little while for the mice to take the tumour," Doug Ford said.

Ford explained that there are dozens of chemotherapy drugs available to treat cancer, and it's often difficult for doctors to choose which course of treatment to follow.

"Right now, the doctors have to guess at what type of chemo will work. And they can do a whole (chemo round )and it may not work. So if, at least, you can narrow it down to see what chemo works on a mouse, it's a massive help," he said.

The precision chemotherapy program at Mount Sinai has been dubbed the Panov Program after patient Yaron Panov, who successfully underwent precision medicine almost two years ago, for the same kind of cancer Ford has.

Panov and his wife Dr. Rochelle Schwartz have since helped raise more than $1 million to fund the precision chemotherapy research at Mount Sinai.

Ford says he would like to see this form of medicine offered throughout Canada. The approach isn't cheap, as it involves lengthy and expensive lab work on the mice and the drug testing. But he says it should be expanded across the country to save time when treating certain cancers.

"Every cancer patient should have a mouse," he told CP24. "I know it sounds crazy but it really helps to narrow down the best treatment."

Meanwhile, the family has just started a "Get well soon" website where the public can send messages of encouragement.

"There's thousands of messages coming through to him from right across Canada and the U.S. and we just appreciate all the prayers and thoughts," Ford said, adding that the messages help pick up his brother's spirits.

"...A few people have emailed in and said, 'Hey, I never voted for you, but I want to wish you all the best and we need you back there. So it's encouraging."