Physicians and researchers are recognizing that each cancer, like each patient, is different. Even when patients have the same type of cancer, responses and cancer cell behaviors can vary. Scientists are moving toward understanding why these variations exist and how to target them for improved outcomes.

Having decoded the human genome, scientists also are working to identify more gene receptors on cancer cells. This will help doctors determine which treatments will be most effective. For example, tests currently are available to predict the likelihood of recurrence, potential response to some drugs and the presence of cancer targets that new drugs can directly attack. The days of one-size-fits-all treatments are drawing to a close.