I think that "accuracy" isn't as easy to define as you'd like. There are keratoses which just fall off if left untreated, and these are not considered cancer, b

I think that "accuracy" isn't as easy to define as you'd like. There are keratoses which just fall off if left untreated, and these are not considered cancer, but the cells are indistinguishable from certain skin cancers under a microscope. Since it may not be obvious whether something will just fall off if left to itself, and "wait and see" isn't an ideal approach for dealing with something that might be cancer, these often get treated, leaving whether they were 'really' cancer unknowable to modern medicine.