Surgery to remove a triangle-shaped slice of tissue. It may be used to remove a breast tumor and a small amount of normal tissue around it.

Also called allopathic medicine, conventional medicine, mainstream medicine, and orthodox medicine. A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists and therapists) treat symptoms and diseases using medicines, radiation therapy or surgery. Western medicine is based on the notion of a risk-benefit analysis: a benefit must outweigh the risks of a treatment before it is considered a reasonable option. Western medicine is distinct from alternative medicine, a term used for treatment systems opposed to pharmaceutical and surgical methods. Alternative treatments can make their way into Western medicine's partnership with complementary or integrative medicine when those treatments are proven safe and effective through scientific means, or when the benefits outweigh the risk of a treatment.

Also called leukocyte and WBC. A type of immune cell. Most white blood cells are made in the bone marrow and are found in the blood and lymph tissue. White blood cells help the body fight infections and other diseases. Granulocytes, monocytes, and lymphocytes are white blood cells.

WGA study. A study that compares the complete DNA, or genomes, of people with a disease or health condition to the DNA of people without the disease or condition. These studies find the genes involved in the development of a disease and may lead to better strategies to help prevent, diagnose and treat the illness. Also called genome-wide association study, GWAS.

A procedure performed right before an operation during which a needle (wire) is inserted, with mammographic or ultrasonographic guidance, into an area in the breast to mark the location of a lesion that cannot be easily found by the surgeon often due to its small size. The procedure guides the surgeon to what tissue should be removed in a surgical biopsy or lumpectomy.