Table 1.

Familial relative risks for lymphoid malignancies and all hematological malignancy, stratified by the age at diagnosis

	Age groups, y*	N	SIR (95% CI)	P
All hematological malignancies	≤56	2070	1.38 (1.32-1.44)	.05
	>56	4150	1.31 (1.27-1.35)
ALL	≤5	6	2.51 (0.60-5.66)	.69
	>5	8	0.36 (0.01-2.03)
HL	≤28	45	5.76 (4.20-7.70)	7.3 × 10−3
	>28	61	3.36 (2.57-4.32)
Nodular sclerosis HL	≤22	6	14.29 (5.24-31.09)	.29
	>22	10	8.20 (3.93-15.07)
NHL	≤57	392	1.76 (1.59-1.95)	.89
	>57	792	1.75 (1.63-1.87)
DLBCL	≤59	18	2.65 (1.57-4.18)	.44
	>59	30	2.10 (1.42-3.00)
FL	≤56	6	2.02 (0.74-4.40)	.78
	>56	12	1.76 (0.91-3.07)
LPL	≤65	8	19.05 (8.22-37.53)	.53
	>65	8	13.79 (5.95-27.18)
MCL	≤63	3	13.64 (2.81-39.85)	.93
	>63	5	13.16 (4.27-30.71)
CLL	≤63	148	6.99 (5.91-8.21)	1.1 × 10−3
	>63	169	4.83 (4.13-5.62)
MM	≤63	92	2.24 (1.81-2.75)	.52
	>63	136	1.96 (1.72-2.43)
Myeloid malignancies	≤56	167	2.19 (1.87-2.55)	.13
	>56	312	1.89 (1.69-2.11)
MPN	≤59	80	6.46 (5.12-8.04)	4.0 × 10−3
	>59	101	4.15 (3.38-5.04)
PV	≤59	26	10.90 (7.12-15.97)	.03
	>59	27	5.96 (3.93-8.67)
ET	≤56	10	9.76 (4.68-17.95)	.17
	>56	12	5.37 (2.77-9.38)
CML	≤47	2	1.33 (0.16-4.80)	.39
	>47	2	0.55 (0.07-1.99)
MDS	≤68	13	11.95 (6.36-20.43)	8.8 × 10−3
	>68	5	3.27 (1.06-7.63)
AML	≤52	13	1.48 (0.79-2.53)	.90
	>52	33	1.55 (1.07-2.18)

^*Age group is defined by the lower quartile of the distribution of the diagnosis. P represents a trend test. The age stratification was based on the first quartile of the age at diagnosis distribution of all incident cases for each hematological malignancy. Where a first-degree relative appears in both age groups as a result of being related to 2 or more incident cases, the first-degree relative is counted in the younger age group. Data on the clonal myeloid neoplasms have previously been reported.¹⁸

N, number of cases.