NCI Dictionary of Cancer Terms The NCI Dictionary of Cancer Terms features 7,942 terms related to cancer and medicine. The search textbox has an autosuggest feature. When you enter three or more characters, a list of up to 10 suggestions will popup under the textbox. Use the arrow keys to move through the suggestions. To select a suggestion, hit the enter key. Using the escape key closes the listbox and puts you back at the textbox. The radio buttons allow you to toggle between having all search items start with or contain the text you entered in the search box. Starts with Contains Browse: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # myeloma listen (MY-eh-LOH-muh) Cancer that arises in plasma cells, a type of white blood cell. More Information Plasma Cell Neoplasms (Including Multiple Myeloma) Enlarge Multiple myeloma. Multiple myeloma cells are abnormal plasma cells (a type of white blood cell) that build up in the bone marrow and form tumors in many bones of the body. Normal plasma cells make antibodies to help the body fight infection and disease. As the number of multiple myeloma cells increases, more antibodies are made. This can cause the blood to thicken and keep the bone marrow from making enough healthy blood cells. Multiple myeloma cells also damage and weaken the bone.