Myeloma is a type of cancer that develops from cells in the bone marrow called plasma cells. Bone marrow is the spongy tissue found inside the inner part of some of our large bones. The bone marrow produces different types of blood cells.
Myeloma can develop wherever there are plasma cells. So it can be anywhere there is bone marrow, including the pelvis, spine and ribcage. As it can occur in several places in the body, it is often called multiple myeloma