Picture this: A cancer patient visits her oncologist, gives a few drops of blood or a biopsy specimen, and is told that her genetic expression pattern shows she has a certain subtype of disease. Meanwhile, another expression pattern predicts that her genetic profile should respond well to chemotherapy regimens A and B (with minimal side effects). During her treatments, protein expression patterns are used to make sure that her treatment is effectively disrupting the targeted cellular pathway in her tumor. After treatment, more gene and protein expression patterns verify that the cancer is in remission.