Criteria for the classification of monoclonal gammopathies, multiple myeloma and related disorders: a report of the International Myeloma Working Group.

The monoclonal gammopathies are a group of disorders associated with monoclonal proliferation of plasma cells. The characterization of specific entities is an area of difficulty in clinical practice. The International Myeloma Working Group has reviewed the criteria for diagnosis and classification with the aim of producing simple, easily used definitions based on routinely available investigations. In monoclonal gammopathy of undetermined significance (MGUS) or monoclonal gammopathy, unattributed/unassociated (MG[u]), the monoclonal protein is /= 30 g/l and/or bone marrow clonal cells >/= 10% but no related organ or tissue impairment (ROTI)(end-organ damage), which is typically manifested by increased calcium,…