Table 2.

Malignant transformation in patients with IgM MGUS

Author	No. with IgM MGUS	Median follow-up	No. progressing to WM (%)	Median time to progression	# other LPD
All MGUS
Cesana (22)	130	67 mo	12 (9.2)	89 mo	—*
Blade (31)	14	56 mo	1 (7.1)	n.r.	—
Anagnostopoulos (37)	4	71 mo	0 (0.0)	n.a.	—
Colls (52)	3	4 yrs	2 (66.7)	3 yrs	—
van de Donk (53)	9	6.75 yrs	1 (11.1)	9.46 yrs	—
Veneri (54)	71	67 mo	8 (11.3)	n.r.	—
IgM MGUS
Kyle (3)	213	6.3 yrs	6 (2.8)	> 5 yrs**	17 NHL, 3 CLL, 3 AL, 1 MM***
Montoto (55)	52	5 yrs	5 (9.6)	3.6 yrs	1 NHL
Baldini (56)	217	56.1 mo	13 (6.0)	n.r.	2 NHL
Morra (57)	452****	49 mo	36 (8.0)	53 mo	2 NHL, 1 CLL, 1 AL, 1 MM

Abbreviations: MGUS, monoclonal gammopathy of undetermined significance; No., number; mo, months; yrs, years; n.r., not reported; n.a., not applicable

^*Cannot be determined from the data

^**For 5 of 6 patients

^***Patient developed a biclonal IgM/IgA gammopathy and subsequently developed IgA myeloma.

^****Included patients with asymptomatic IgM monoclonal gammopathy