About Breast Cancer
“Cancer” is a general term that describes the more than 200 human diseases that are classified as leukemias, lymphomas, myelomas, and solid tumors. The term also applies to similar conditions in animals. Simply put, any disease in which cells endlessly divide is called “cancer.” It’s a mistake, however, to think that all cancers are the same and that where cancer occurs in the body doesn’t change the nature of the disease. Each type of cancer is unique in its cause, biochemistry, course of development, and response to treatment. Thus, breast cancer, prostate cancer, and colon cancer in humans are not the same disease.
Just as cancerous breast cells are different from cancerous colon cells in humans, breast cells in humans are also vastly different from breast cells in mice. Because breast cancer is a human disease that predominantly strikes women, animal tests are ineffective because they fail to study the unique biochemistry of cells that are both human and female. In fact, in a major drug review, cancer induction was so inconsistent between species and gender that 46 percent of the chemicals that caused cancer in rats didn’t cause cancer in mice, and of the 33 chemicals that caused cancer in both rats and mice, only 13 caused cancer in both sexes.1 The absurdity of testing human cancer drugs on animals is clear—you can’t learn about one species by conducting experiments on another.
1. C. Ray Greek and Jean Swingle Greek, Sacred Cows and Golden Geese: The Human Costs of Experiments on Animals (New York: Continuum, 2000) 132.
