Cancer is an umbrella term for a large group of diseases caused when abnormal cells divide and invade other tissue and organs. Cancer is the second leading cause of death in the U.S., and more than 1.5 million Americans are diagnosed with some form of it every year. According to the American Cancer Society, half of all men and a third of all women in the U.S. will develop cancer in their lifetimes.
While breast pain or lumps are often associated with breast cancer, they can be benign symptoms of stress, hormonal changes, or even an ill-fitted bra. Regular self-examination can help determine whether breast pain or lumps indicate a more serious condition.