These gross images reveal severe bullous emphysema of the lungs. There is a very large bulla involving the left lung, seen in the topmost image. The cross section of the lung reveals a centrilobular pattern of emphysema, with loss of lung tissue in the center of lung lobules accompanied by extensive deposition of black anthracotic pigment. The most common cause for centrilobular emphysema is smoking. Emphysema is now the fourth leading cause of death in the U.S. Though persons who smoke can reduce their risk for lung cancer by quitting, it should be emphasized--particularly to young persons who begin to smoke--that emphysema represents a loss of lung tissue, and this damaage is cumulative and permanent!