The past few years have seen tremendous strides in our understanding of cancer, including new hypotheses about its genetic origins and new treatment alternatives using the body’s own immune response. In this eBook, The Science of Cancer, we examine what we know and what we’re finding out about this scourge of humankind. We delve into the molecular basis and complex causes of cancer, the arguments for and against screenings, new and targeted therapies, and minimizing risk. In “How Cancer Arises,” Robert Weinberg presents what has been the central dogma of cancer genetics, which says that a handful of essential mutations in specific genes lead to tumor growth; however, recent discoveries are challenging this theory, as we see in “Untangling the Roots of Cancer” and “Stem Cells: The Real Culprits in Cancer?” Early detection of cancer is important for treatment, but not all screening tests are created equal. In “The Great Prostate Cancer Debate,” Mark Garnick lays out the controversy over the value of the prostate-specific antigen test for prostate cancer and the rationale against screening. With our increasing knowledge of cancer’s causes, exciting targeted therapies are on the rise, including homing in on stem cells, making use of viruses, and manipulating the immune system as we see in “A New Ally against Cancer,” which focuses on treatment with therapeutic vaccines. Does this mean a cure is around the corner? Perhaps not, according to Scientific American Editor Dina Fine Maron in “Can We Truly ‘Cure’ Cancer?” But with remission rates rising for certain types of cancers and with new discoveries opening up further avenues of research, there is reason for optimism.