I've been adjacent to this field for a while, so take this for what it is. My understanding that the developing a system that can accurately identify a specific form or sub-form of cancer to a degree equal or better than a human is doable now. However, developing a system that can generalize to many forms of cancer is not.
Why does this matter? Because procurement in the medical world is a pain in the ass. And no medical center wants to be dealing with 32 different startups each selling their own specific cancer detection tool.