Table II.

Characteristics of MGUS cohorts and incidence of multiple myeloma (MM) or other lymphoid cancers (LC) in different studies.

Study	Reference population	N. of subjects	Age at diagnosis	M-protein (g/dL) at diagnosis	Incident MM/LC cases	Person-years of observation	Incidence rate/100 person-years	Difference in incidence from Trieste cohort*
Trieste cohort	blood donors	88	53 median 51 mean	0.2 median 0.3 mean	1	648	0.15	——
Van de Donk 2001 (15)	clinical setting	88	56 median	1.1 median	12	686	1.75	P=0.006
Kyle 2004 (12)	clinical setting	241	64 mean	1.8 mean	64	3,579	1.79	P=0.001
Gregersen 2001 (13)	clinical setting	1,247	68 mean	0.7–1.5 median	107	6,802	1.57	P=0.002
Kyle 2002 (2)	clinical setting	1,384	72 median	1.2 median	115	11,009	1.04	P=0.03
Rossi 2009 (16)	clinical setting	905	63 median	32% >1.5	77	6,467	1.19	P=0.01
Bida 2009 (9)	population based	605	70 mean	0.5 median	77	14,373	0.54	P=0.26

Legend:

^*Mid-P exact (2 tailed).