Table 1.

Baseline clinical and pathologic characteristics of all 55 patients with SBP who had cytogenetics by FISH available

Characteristic	High risk (n = 22; 40%) n (%)	Standard risk (n = 33; 60%), n (%)	P value
Median age, y (range)	62 (28-78)	62 (29-83)	.72
Male	16 (73)	22 (67)	1.00
White	17 (77)	31 (91)	.127
Serum monoclonal protein detectable∗	21/21 (100)	32/32 (100)	1.00
M spike (g/dL), median (range)	0.75 (0.4-1.9)	1 (0.4-1.8)	.436
Abnormal FLC ratio†	14 (64)	18 (55)	.373
Maximal SBP diameter of 5 cm or greater	8/11 (73)	8/24 (33)	.035
Minimal marrow involvement present‡	20 (91)	21 (64)	.029
High-risk cytogenetic subtype§
Del (17p)	11 (50)	—
Gain (1q)	13 (59)	—
t(4;14)	2 (9)	—
t(14;16)	1 (5)	—
t(14;20)	0	—

The boldface P values are statistically significant at P < .05.

^∗Detectable by either immunofixation or mass-fixation

^†Abnormal ratio defined as <0.26 or >1.65

^‡Clonal plasma cells were considered positive if monoclonal plasma cells were detected by flow cytometry or immunohistochemistry on the bone marrow biopsy core or aspirate.

^§Some patients have multiple different high-risk cytogenetic subtypes and are counted in each category.