Medical Glossary W

Waldenstrom's macroglobulinemia: This is a rare, chronic cancer that affects white blood cells called B lymphocytes, or B cells. These cells form in the lymph nodes and the bone marrow, the soft, spongy tissue inside bones, and are an important part of the body's immune (defense) system. Some B cells become plasma cells, which make, store, and release antibodies. Antibodies help the body fight viruses, bacteria, and other foreign substances. In Waldenstrom's macroglobulinemia, abnormal B cells multiply out of control. They invade the bone marrow, lymph nodes, and spleen and produce excessive amounts of an antibody called IgM.

warfarin: A drug that prevents blood from clotting. It belongs to the family of drugs called anticoagulants (blood thinners).

Wart: A raised growth on the surface of the skin or other organ.

WBC: Cells that help the body fight infections and other diseases. Also called white blood cells (WBCs).

Whipple procedure: A type of surgery used to treat pancreatic cancer. The surgeon removes the head of the pancreas, the duodenum, a portion of the stomach, and other nearby tissues.

White blood cells: Cells that help the body fight infection and disease. These cells begin their development in the bone marrow and then travel to other parts of the body.

Wilms' tumor: Wilms' tumor is a disease in which cancer (malignant) cells are found in certain parts of the kidney. The kidneys are a "matched" pair of organs found on either side of the backbone. Inside each kidney are tiny tubes that filter and clean the blood, taking out unneeded products, and making urine. Wilms' tumor occurs most commonly in children under the age of 15 and is curable in the majority of affected children.