Plasma cell neoplasms including multiple myeloma (MM) and related terminally differentiated B-cell neoplasms are characterized by secretion of monoclonal immunoglobulin and stepwise development from a preneoplastic clonal B and/or plasma cell proliferation called monoclonal gammopathy of undetermined significance (MGUS). Diagnosis of these disorders requires integration of clinical, laboratory, and morphological features.
Myeloma
Revised IMWG Diagnostic Criteria for Multiple Myeloma
This International Myeloma Working Group consensus updates the disease definition of multiple myeloma to include validated biomarkers in addition to existing requirements of attributable CRAB features (hypercalcaemia, renal failure, anaemia, and bone lesions).
Diagnostic Criteria for Plasma Cell Myeloma (PCM)
The definition of plasma cell myeloma (PCM) has rested on identifying clinical and laboratory features that predict when a sufficient burden of plasma cells has accumulated that the patient will benefit from treatment.
Diagnostic Criteria for Multiple Myeloma
Presence of an M-componenta in serum and/or urine plus clonal plasma cells in the bone marrow and/or a documented clonal plasmacytoma.