Cancer

in Science

ImageCancer—it’s scary word, and a scary disease. Cancer kills a lot of people all over the world. Only heart disease kills more Americans.

But there’s good news too. Millions of people who have had cancer are still alive. Doctors have learned a great deal about treating and preventing cancer.

WHAT IS CANCER?

Cancer is not a single disease. It includes more than 100 different diseases. They may affect any part of the body. But they have one thing in common. They are all caused by cells that are out of control.

All living things are made up of cells. An adult human body has about 30 trillion cells—that’s 30,000,000,000,000! Cells reproduce (make more cells) by dividing in half. In an adult body, about 25 million cells divide every second. That’s how the body heals itself.

Sometimes a cell goes out of control and divides over and over. And that’s what cancer is—unhealthy cells, growing and reproducing out of control. These cells are said to be cancerous.

WHY CANCER IS DANGEROUS

When cancerous cells multiply, they form clumps called tumors. Tumors can interfere with important body processes. Cancer of the lungs, for instance, interferes with breathing. Cancer of the stomach interferes with digesting food.

Cancerous cells can also spread to other parts of the body. Then new tumors form. This spreading is called metastasis. Cancer that has metastasized is the most dangerous. When cancer attacks several parts of the body, it is hard to stop.

HOW DOCTORS TREAT CANCER

The best weapon against cancer is detecting it at an early stage before it grows very much. Regular checkups by a doctor can detect cancer before it grows and spreads. People whose cancers are discovered early usually survive.

Some cancerous tumors can be removed by surgery. Doctors must remove some surrounding healthy cells, too, to be sure they get all the cancerous cells.

Radiation, such as X rays, can also kill cancer cells. So can treatment with powerful drugs, called chemotherapy. Unfortunately these treatments destroy healthy cells too. They can make people very sick. Newer treatments encourage the body’s own disease-fighting immune system to destroy cancer cells. But the newer treatments don’t work for all types of cancer.

WAYS TO PREVENT CANCER

There is no sure way to avoid cancer. But there are things people can do to greatly reduce the risk of getting cancer.

Smoking causes cancer. People who smoke get lung cancer 20 times more often than people who don’t smoke. Don’t smoke!

Doctors suspect that eating certain foods can also increase the chances of getting cancer. Eating lots of red meat and other foods high in saturated fat may make people more likely to develop cancer.

Most skin cancer is caused by too much Sun. Avoid getting sunburned. If everyone wore sunscreen or stayed out of the Sun, most cases of skin cancer would be prevented.

Source: Microsoft ® Encarta