Table 2.

Definition of multiple myeloma based on 2014 IMWG criteria

Criteria	Description
1	Clonal bone marrow plasma cells ≥10% or biopsy-proven bony or extramedullary plasmacytoma
2	Any 1 or more of the below listed myeloma defining events (which has to be attributed to the underlying plasma cell proliferative disorder): • Hypercalcemia: serum calcium >0.25 mmol/L (>1 mg/dL) higher than the upper limit of normal or >2.75 mmol/L (>11 mg/dL) • Renal insufficiency: creatinine clearance <40 mL/min and/or serum creatinine >173 μmol/L (>2 mg/dL) • Anemia: hemoglobin value of >2.0 g/dL below the lower limit of normal, or a hemoglobin value <10.0 g/dL • Bone lesions: 1 or more osteolytic lesions on skeletal radiography (ie, X-ray), low-dose CT, or PET-CT • Clonal bone marrow plasma cell percentage ≥60% • Involved/uninvolved serum free light chain ratio ≥100, and the involved serum free light chain concentration 10 mg/dL or higher • Two or more focal lesions based on MRI studies of the skeleton

Both criteria have to be fulfilled. Adapted from Rajkumar et al.⁸