Researchers treat breast cancer in cats to save human lives

They give humans warmth and companionship, and plenty of fodder for conversation.

Now researchers hope that cats can give us something else — a better treatment for breast cancer.

Researchers from McMaster University and the Ontario Veterinary College in Guelph have conducted trials on six house cats with breast cancer so far, and expect to do three more in the next month.

The team injects the family pets with an immune booster, followed by a second shot that kills the tumour from inside. The treatment is called oncolytic virus therapy.

In a year, if the results are positive, they’ll try to apply the method to human breast cancer patients too.

The work started when Brian Lichty, a professor of pathology and molecular medicine at McMaster's Immunology Research Centre, teamed up with Paul Woods and Byram Bridle from the Ontario Veterinary College at the University of Guelph.

Scientists often conduct trials in mice, Lichty said. But genetically, cats have more in common with humans.

Breast cancer hits cats the same as it does for humans, he said. It's typically a highly aggressive and fatal disease for cats, returning months after surgeons remove the affected mammary glands.

The first injection happens before surgery, Lichty said. About a month after the surgery, the cats get a second injection.

Researchers won’t know until at least a year from now whether the injections quelled the disease. Breast cancer spreads aggressively in cats, moving on to the lymph nodes and other areas, and tends to reappear six to eight months after surgery, said Woods, who specializes in cancer treatments for cats and dogs.

The first cat treated was Maci, a 12-year-old feline from Toronto.

Cat owners have since stepped forward in droves, eager for any cure for their pets. The team expects to treat nine by the end of the year, and 24 altogether.

It’s a trial that benefits both species equally, unlike traditional mouse trials, Lichty said.

“This is a partnership between the owners, the vets and the funders that I think is a much more positive way to find treatments that are useful,” he said.

Female cats have eight mammary glands. Breast cancer typically strikes older female cats, Lichty said. Owners discover it when they pick up their cats and notice lumps.

“Unfortunately, it’s not usually right away,” he said.

The Canadian Breast Cancer Foundation is funding the project.