So, screening makes total sense if you're a rabbit but won't help if you're a turtle or bird. No one wants to go through the trauma and expense of unnecessary surgery, but this is what happens when doctors operate on either a turtle or a bird. If you're being treated, both you and your oncologists want to believe you're a rabbit and that the procedure will save your life.
It's called the "hypothetical rabbit problem" because the rabbit may not exist. Most of the time, doctors are either operating unnecessarily on turtles (whose cancer would never have been a problem) or uselessly on birds (whose surgery is futile, too little and too late). How to know which, while the patient is alive and treatable? (Autopsies give the final word.) The best oncologists can do is to assign probabilities based on the patient's age, health, medical history, family history, etc. This method, apparently, isn't much better than a crapshoot when pitted against an enemy that's devious, stealthy, fast-moving and — in the case of turtles — may best be left alone.