Cancer is not a single disease, but rather a monster with many faces. Doctors and scientists have listed more than 200 varieties of cancer, each having different degrees of mortality, different means of prevention, different hopes for a cure. Carcinomas hit mucous membranes or the skin, sarcomas attack the tissues under the skin, and leukemia strikes at the marrow—and these are just a few varieties of cancer. Cancers are all characterized by an uncontrolled proliferation of cells under pre-existing tissues, producing abnormal growths. Yet popular attitudes toward cancer have been less bothered with medical distinctions than with providing a single characterization of the disease, evoking a slow and painful process of decay that comes as a sort of punishment for the patient. "Cancerphobia" is, as Susan Sontag and James T. Patterson have shown, deeply rooted in American culture.

Cancer is a very ancient disease, dating back to pre-historic...