There is no environmental factor listed among the established factors that are known to cause breast cancer. Physicians are familiar with those established factors. They know that a woman's age, her menstrual history, her age when she had her first child and her family history are all factors that could increase her risk for breast cancer. Yet physicians also know that such established factors cause only 25% to 50% of the reported cases of breast cancer.
That fact strongly suggests the existence of at least one environmental factor that can produce the unchecked growth of breast cells. In other words, at least one environmental factor puts women at a greater risk for breast cancer. At least one environmental factor lurks in the air that women breathe, the food that women eat, the beverages that women drink or the materials that touch their skin.
Some chemicals are not serious carcinogens when diluted by the air and water, but those same chemicals may not always remain diluted. Those chemicals could become concentrated in animal fat, and a human could then eat that animal. That would expose the human to a dangerous environmental factor.
Some chemicals are harmless until they enter the human system. Some chemicals are "activated," i.e. changed into carcinogens, by enzymes in the human system. While more studies are needed in order to confirm an association between breast cancer and a certain environmental factor, such an association has been found for other cancers.
Studies done at M.D. Andersen Cancer Center in the early 1970's showed that the enzyme called Aryl Hydrocarbon Hydroxylase (AHH) could activate benzopyrene, a chemical in cigarette smoke. Individuals who produced large quantities of AHH appeared to have a greater chance of developing lung cancer. Could enzymes activate an environmental factor, making it capable of causing breast cancer?
Research has established a connection between some environmental factor influences and breast cancer. For example, data has been collected from 63 studies that looked at one of the environmental factor influences. Those studies evolved out of concern over the effects of alcohol consumption. Those studies showed that in 65% of the reported cases of breast cancer, an increase in the rate of breast cancer could be linked to an increased consumption of alcohol.
Sometime researchers discover a chemical that shows no signs of causing cancer, but does appear to be an anti-cancer agent. The antioxidants in certain foods are one example of such anti-cancer agents. Research at UCLA suggests that the drug Celebrex could also be classed as an anti-cancer agent. It seems to enhance the effects of the chemotherapy given to the breast cancer patients.
More studies must be conducted, in order to confirm or deny the suspected ability of Celebrex to enhance the action of the cancer-fighting drugs. More studies, too, should be conducted, with an eye toward discovery of at least one environmental factor that appears able to breast cancer.