Table 1. Diagnostic criteria of the International Myeloma Working Group (e18).

	MGUS	Smoldering myeloma	Symptomatic multiple myeloma
Proportion of plasma cells in bone marrow	<10%	≥ 10%	≥ 10%
M protein in serum	<30 g/l	≥ 30 g/L	Detectable in serum and/or urine
End-organ damage (CRAB)	No	No	Present

CRAB criteria: hypercalcemia, renal insufficiency, anemia, bone lesions

MGUS, monoclonal gammopathy of uncertain significance