On Saturday, the University of Chicago Medical Center hosted the third of eight free lectures in a series titled, “Blood, Stem Cells and Cancers of the Blood.” Wei Xu, a Ph.D. candidate at the University of Chicago, first explained basic cancer terminology and then presented an overview of three blood cancers: leukemia, lymphoma, and myeloma.

Xu explained that a neoplasm is an abnormal proliferation of cells. Two examples of neoplasm are a tumor and cancer. A tumor is a solid neoplasm than can be either benign or malignant. A benign tumor is harmless and will not invade other tissues of the body. A malignant tumor, however, is harmful and can invade other parts of the body.

Cancer is a neoplasm that is malignant. It may take the form of a tumor but does not have to, as in leukemia. Metastasis occurs when cancerous cells spread—usually via the bloodstream—and create colonies in other parts of the body. If metastasis is not controlled, death can result. Blood cell cancers can affect the blood (leukemia), lymph nodes (lymphoma), or bone marrow (myeloma).

Leukemia is the uncontrolled proliferation of large numbers of abnormal white blood cells, which normally defend the body against infections. These non-tumorous cells take over the bone marrow and often spill into the bloodstream, which can lead to metastasis.

Lymphoma is a tumor of the lymphoid tissue, which is tissue that is part of the body’s immune system, such as the lymph nodes, bone marrow, liver, and spleen. Lymphoma is the uncontrolled production of lymphocytes, a type of white blood cell, in this tissue. These tumors can overwhelm neighboring tissue, thereby depriving it of oxygen and other nutrients needed to survive. Abnormal lymphocytes can also spread through the lymphatic system and into other types of tissue.

Myeloma is a special type of lymphoma that affects plasma cells—mature cells that produce antibodies, which are important for fighting infections. Myeloma is caused by the uncontrolled proliferation of plasma cells within bone marrow.

Myeloma tumor growth is typically restricted to the bone and does not accumulate in the blood. Accumulation in the bone, however, can lead to bone destruction ^[1] and be associated with kidney problems.

Xu also discussed myelodysplastic syndromes ^[2] (MDS), which are a group of disorders related to cancer. In MDS—sometimes referred to as “pre-leukemia”—immature blood cells called blast cells fail to grow and develop normally.

For information about future seminars, see the University of Chicago’s lecture series Web site ^[3].