Multiple Myeloma

Multiple Myeloma is a cancer of antibody producing plasma cells.  It is characterized by an accumulation of plasma cells in the bone marrow.  The expansion of these cells negatively impacts the normal function of the bone marrow limiting the production of red blood cells (anemia/fatigue) and other white blood cells (WBC), which compromises the immune system and results in recurrent infections.  In a large number of patients the plasma cell expansion causes a severe form of osteoperosis resulting in bone lesions that can cause broken bones, losses in height due to vertebral collapse, and soft spots in the skull.
Pathology of the Disease

Fig 1 - Representative pictures of a normal bone marrow and a bone marrow from a patient with multiple myeloma.  Notice the large cells in the myeloma example that make up most of the cells, which are not seen in the tumor sample.