Multiple myeloma is a rare form of blood cancer that affects the bone marrow, where the body makes blood cells. It develops in the plasma cells, a type of white blood cell that makes the antibodies that protect your body from infection, leading to a weakened immunity system. It can also cause anemia as it can impact the development and viability of red blood cells. Detection is done through blood, urine and blood marrow tests. Imaging tests, such as X-ray, MRI or CT scan, can show irregularities in the bone, as well. Multiple myeloma can spread to other parts of the body, such as the bones and kidneys.