Table 1.

Summary of morphologic findings

	HCL	HCL-v	SMZL
BONE MARROW
Cellularity
Hypercellular	54% (44/82)	43% (6/14)	N/A
Normocellular	18% (15/82)	28.5% (4/14)	N/A
Hypocellular	28% (23/82)	28.5% (4/14)	N/A
Infiltration pattern
Interstitial	24% (20/82)	50% (7/14)	N/A
Interstitial with aggregates	21% (17/82)	36% (5/14)	N/A
Sheets	55% (45/82)	14% (2/14)	N/A
Level of marrow infiltrate
75–100%	73% (60/82)	21% (3/14)	N/A
25–75%	22% (18/82)	50% (7/14)	N/A
Less than 25%	5% (4/82)	29% (4/14)	N/A
Immunostaining for TRAP
Positive for TRAP	95% (73/77)	38% (5/13)	N/A
Negative for TRAP	5% (4/77)	62% (8/13)	N/A
Residual hematopoiesis
Markedly suppressed	63% (52/82)	21% (3/14)	N/A
Present	37% (30/82)	79% (11/14)	N/A
CYTOMORPHOLOGY
Cytoplasmic projections
Present	94% (67/71)	96% (25/26)	33% (2/6)
Absent	6% (4/71)	4% (1/26)	67% (4/6)
Nuclear Shape
Round	77% (55/71)	92% (24/26)	33% (2/6)
Atypical (dumbbell-shape, irregular, grooves)	23% (16/71)	8% (2/26)	67% (4/6)
Nucleoli
Absent	79% (56/71)	0% (0/26)	17% (1/6)
Small and inconspicuous	20% (14/71)	38% (10/26)	83% (5/6)
Prominent	1% (1/71)	62% (16/26)	0% (0/6)

HCL: Hairy cell leukemia, HCL-v: Hairy cell leukemia-variant, SMZL: Splenic marginal zone lymphoma, N/A: not available.