Cancer isn’t just one disease. It is a large and complex family of malignancies that can affect virtually every organ in the body. Cancer is second only to heart disease as the leading cause of death in the United States. Over 1.2 million new cases are diagnosed every year, with half of them occurring in the lung, prostate, breast, colon and rectum. Cancer can strike at any age, although it is most common in people over 50.
Cancer begins in the body’s cells, which are constantly dividing and multiplying to replace old, damaged cells. Sometimes, cells begin to divide unnecessarily, forming excess tissue known as a tumor. In most cases, tumors are benign, meaning that they are not cancerous. Benign tumors, although they may cause some health problems depending on their size and location, are not life-threatening.
However, if an abnormal cell begins to divide, it eventually forms a malignant, or cancerous tumor. Most malignant tumors grow quite rapidly, invading nearby organs and tissues. Cancerous cells can also travel through the bloodstream to other regions of the body. When cancer spreads from its original site, the process is known as metastasis.
The good news is that cancer death rates have been declining in recent years, especially among men, who generally experience higher rates than women. Increasing public awareness has resulted in more people getting regular cancer screenings, and practicing healthy lifestyles to reduce their risk.