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

Abstract

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 the bone marrow clonal cells < 10% with no evidence of multiple myeloma, other B-cell proliferative disorders or amyloidosis. In asymptomatic (smouldering) myeloma the M-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, renal insufficiency, anaemia, or bone lesions (CRAB) attributed to the plasma cell proliferative process. Symptomatic myeloma requires evidence of ROTI. Non-secretory myeloma is characterized by the absence of an M-protein in the serum and urine, bone marrow plasmacytosis and ROTI. Solitary plasmacytoma of bone, extramedullary plasmacytoma and multiple solitary plasmacytomas (+/- recurrent) are also defined as distinct entities. The use of these criteria will facilitate comparison of therapeutic trial data. Evaluation of currently available prognostic factors may allow better definition of prognosis in multiple myeloma.

Concomitant HIV infection in newly diagnosed multiple myeloma patients is hard to recognise and should be tested for routinely in areas of high endemicity

“…Diagnosis was based on the then current diagnostic criteria of the International Myeloma Working Group of 2003 and clinical opinion of the haemato-oncologist, and may not meet the diagnostic criteria currently used. [22] All plasmacytomas were histologically confirmed. The stage of disease was based on the International Staging System (ISS), which relies on serum albumin and β2-microglobulin (B2M) levels.…”

Neuroimaging of Plasmacytoma

“…The osseous form of plasmacytoma usually progresses to multiple myeloma in three to five years. The incidence of plasmacytoma is more common in males and the 55-75 year age group 1,3 . Clinical presentation of patients depends on the location of the lesion and mass effect.…”

“…There are three distinct groups of plasmacytoma defined by the International Myeloma Working Group: solitary plasmacytoma of bone (SPB), extramedullary plasmacytoma (EMP) and multiple plasmacytomas that are either primary or recurrent 1,2 . The most common of these is SPB, accounting for 3-5% of all plasma cell malignancies.…”

Anterior horn lesion of spinal cord as the initial manifestation of multiple myeloma: A case report

“…MM is an abnormal proliferation of plasma cells that causes malignant neoplasm, consisting of up to 10% of haematological malignancies [2] and it mainly affects the elderly population [3] . It has relatively non-specific onset symptoms as it shows a variety of clinical manifestations but lacks specificity.…”