Monoclonal gammopathy of undetermined significance (MGUS) is a condition in which an abnormal protein (monoclonal protein, or M protein) is in the blood. M protein is produced by plasma cells, a type of white blood cell. Monoclonal gammopathy of undetermined significance usually causes no problems. Sometimes, monoclonal gammopathy of undetermined significance is either associated with another disease or can progress over years to other disorders, including some forms of blood cancer.

If you have monoclonal gammopathy of undetermined significance, you'll usually have periodic checkups to monitor your level of M protein. If there's no increase, monoclonal gammopathy doesn't require treatment.

With close monitoring, if monoclonal gammopathy of undetermined significance does progress, you'll get earlier treatment.

May. 17, 2013