I don't recall an earlier cancer. He'd announced the year before he died he had prostate cancer, but was very upbeat, noted his father had beaten the same cancer, looked healthy, and little more was said. I don't recall it being used for gain during the election. And I don't recall it ever being mentioned as part of the election campaign by any of the NDP. I suppose the prostate cancer might have been seen as another cancer, that he looked as though he'd beaten.
I think it's clear that he didn't actually beat this cancer, given he was dead with 18 months. I can't recall an earlier one. Chow had cancer before, but that was never used for electioneering much - but perhaps I missed something.
I can't recall ever seeing anything like the grandstanding Ford is doing, by anyone, right or left.