Biopsy: The surgical removal of tissue for microscopic examination to aid in diagnosis.

CAT scan (CT scan): A test using computers and X-rays to create images of various parts of the body.

Chemotherapy: The treatment of cancer with drugs.

MRI (Magnetic resonance imaging): A sophisticated test that provides in-depth images of organs and structures in the body.

Radiation therapy: X-ray treatment that damages or kills cancer cells.

Primary tumor: The original cancer site. For example, breast cancer that has spread to the bone is still called breast cancer.