Breast cancer, which occurs when cells grow out of control, can start in one or both breasts, in different parts of the organ – lobules, ducts, nipple, fat and connective tissue, blood vessels and lymph vessels.

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Although most common in women, men can get breast cancer, too

Signs of breast cancer can include a lump in the breast or arm pit, a change in shape or size of the breast, nipple changes or discharge, and skin changes to the breast.

Risk factors for breast cancer include binge drinking, being overweight, especially after menopause, living a sedentary lifestyle and an unhealthy diet, which are all changeable lifestyle factors. In addition, unchangeable risk factors include female gender, older age, genetics, family history of the disease, personal history of the disease, race and ethnicity, dense breasts, benign breast conditions, exposure to diethylstilbestrol, menstruation, menopause, previous chest radiation and recurrent breast cancer.

Screening for breast cancer includes breast self-exams, clinical breast exams by health care providers and mammograms.

Although breast cancer can be confined to the breasts, it is possible for the cancer cells to invade the bloodstream or lymph system, traveling to other parts of the body, causing spread, or metastasis.