The Basics of Lung Cancer

For many years, lung cancer was a man's disease. Reading lung cancer information has led us to today. Lung cancer is the most common cancer-related cause of death among men and women alike. More lung cancer info has turned up the fact that in 1987, lung cancer surpassed breast cancer to become the leading cause of cancer death among US women.

By 2002 there were about 169,400 new cases of lung cancer in the U.S., accounting for about 13 percent of all cancers: 90,200 among men and 79,200 among women. According to the American Cancer Society, this year, about 154,900 people will die of this disease: 89,200 men and 65,700 women.

Lung cancer occurs most often in people over 50 who have long histories of cigarette smoking. The incidence of lung cancer in women as a whole has climbed at an alarming rate. Since 1950, lung cancer mortality rates for U.S. women have increased an estimated 600 percent. These increases are clearly attributable to the increases in the number of women who have smoked.

Normal lung tissue is made up of cells that are programmed by genes to create tissue in a certain shape and to perform certain functions. Lung cancer develops when the genetic material responsible for production of these cells is damaged. This damage is known as genetic mutations. Lung cancer results as the uncontrolled growth of abnormal cells in the lung. Repeated exposure to carcinogens, such as tobacco smoke, causes the mutations.

Mutations in the genetic material of the lung cells cause the instructions for those cells to go awry. Consequently, those cells and their offspring reproduce at a dramatic pace, without regard for the normal shape and function of a lung. That wild reproduction causes the formation of tumors that may block air passages in the lung and make it stop functioning as it should. Mutations may also prevent normal programmed cell death, thereby adding to the accumulation of cells, and tumor formation.

Some genes are known as tumor suppressors. Their job is to keep abnormal cells from growing and forming tumors. Researchers have determined that a tumor suppressor gene called p53 is almost always defective in cases of small-cell lung cancer, and in approximately half of non-small cell lung cancer cases. Because of the defect in the gene, it does not stop the reproduction of tumor cells as it should.

Copyright 2003 National Women's Health Resource Center Inc. (NWHRC)