LEARNING ABOUT DISEASES: CANCER
Cancer is a wild, unrestrained growth of cells. Some disturbance occurs which disrupts the balance of cells of different kinds in the body. The cells seem to return to their primitive state or to the infantile or fetal type. The body of a baby before birth grows much faster than does a cancer, but the growth of the cells in the developing child is controlled or regulated by an internal mechanism.
Many substances have the ability to stimulate the growth of cells. Pure chemicals, glandular substances, or physical forces like heat or pressure may stimulate cell growth. The changes that initiate the sudden, rapid growth of cancer cells and the traveling of these cells into other parts of the body involve many different factors related to the chemistry of the body, its nutrition, damage to tissues by inflammation and infection, and modifications of growth brought about by glandular action.
A variety of chemical products, particularly those related to tar, are known to be able to stimulate the growth of cancer. In tropical areas white people who do not protect themselves against the sun develop cancer in amounts out of all proportion to that which occurs among the native people with darker skins. To a large extent farmers also, as well as sailors, suffer from cancers of the skin.
Irritation is still a basic factor in the production of cancer. Continuous rubbing, irritation by irregular or jagged teeth, and heat from a pipe carried always in one corner of the mouth are known to be types of irritation that can excite the growth of cancer.
