Even removing part of a tumour for laboratory examination reveals little about what it will do in the future.

ECONOMIST: The ne plus ultra of medicine | The

Reams of research point to the same finding: physicians looking at the same thing will disagree with each other, or even with themselves, from 10 percent to 50 percent of the time during virtually every aspect of the medical-care process from taking a medical history to doing a physical examination, reading a laboratory test, performing a pathological diagnosis and recommending a treatment.

FORBES: Are Medical Treatments Keeping Up With Science?