Newly Diagnosed? What You Need To Know About Lung Cancer

African American doctor looking at lung x-rayThe diagnosis of lung cancer brings with it many questions and a need for clear, understandable answers. We hope this National Cancer Institute (NCI) booklet (NIH Publication No. 99-1553) will help. It provides information about some causes and ways to prevent lung cancer, and it describes the symptoms, detection, diagnosis, and treatment of this disease. Having this important information can make it easier for patients and their families to handle the challenges they face.

Cancer research has led to progress against lung cancer — and our knowledge is increasing. Researchers continue to look for better ways to prevent, detect, diagnose, and treat lung cancer. The Cancer Information Service and the other NCI resources listed under “National Cancer Institute Information Resources” can provide the latest, most accurate information on lung cancer. Publications mentioned in this book and others are available from the Cancer Information Service at 1-800-4-CANCER. Many NCI publications are also available on the Internet at the Web sites listed in the “National Cancer Institute Information Resources” section at the end of this booklet.

Understanding the Cancer Process

All types of cancer develop in our cells, the body’s basic unit of life. To understand cancer, it is helpful to know how normal cells become cancerous.

The body is made up of many types of cells. Normally, cells grow, divide, and produce more cells as needed to keep the body healthy and functioning properly. Sometimes, however, the process goes astray — cells keep dividing when new cells are not needed. The mass of extra cells forms a growth or tumor. Tumors can be benign or malignant.

Benign tumors are not cancer. They often can be removed and, in most cases, they do not come back. Cells in benign tumors do not spread to other parts of the body. Most important, benign tumors are rarely a threat to life.

Malignant tumors are cancer. Cells in malignant tumors are abnormal and divide without control or order. These cancer cells can invade and destroy the tissue around them. Cancer cells can also
break away from a malignant tumor and enter the bloodstream or lymphatic system (the tissues and organs that produce, store, and carry white blood cells that fight infection and other diseases). This process, called metastasis, is how cancer spreads from the original (primary) tumor to form new (secondary) tumors in
other parts of the body.