At a Glance The endocrine system is comprised of glands that secrete hormones—chemical substances that travel in the bloodstream to target tissues, where they help to regulate body growth and direct the development and functioning of primary and secondary sexual...
At a Glance Cancer cells behave differently than normal, healthy cells and tissues. For a long time, cancer was thought to occur because of mutations in the genes (DNA) in individual cells. Newer understandings suggest that the picture is more complex. There are three...
At a Glance While most of us think of breast cancer as a single disease, evidence suggests there are multiple subtypes of breast cancer that occur at different rates in different groups, respond to different kinds of treatment, grow and spread at different rates, and...
At a Glance Globally, breast cancer affects more women than any other type of cancer and is the leading cause of cancer-related deaths among women.[1] In the United States, breast cancer has the highest mortality rate of any cancer in women between the ages of 20 and...
