RAS mutations in early age leukaemia modulated by NQO1 rs1800566 (C609T) are associated with second-hand smoking exposures

Table 1 Demography and clinical characteristics of early age acute leukaemia subtypes, Brazil, 2000-2010

	Total, n (%)	ALL (%) (n = 150)	AML (%) (n = 85)	p
Age (months)
≤12	120 (51.1)	82 (54.7)	38 (44.7)	0.14
13-24	115 (48.9)	68 (45.3)	47 (55.3)
Gender
Male	131 (55.7)	78 (52.0)	53 (62.4)	0.12
Female	104 (44.3)	72 (48.0)	32 (37.6)
Skin colour
White	139 (59.9)	92 (61.7)	47 (56.6)	0.44
Non-White	93 (40.1)	57 (38.3)	36 (43.4)
WBC (x10 ⁹ /L)
≤50	106 (46.5)	59 (40.4)	47 (57.3)	0.01
>50	122 (53.5)	87 (59.6)	35 (42.7)
Chromosomal alterations
MLL ^r	102 (77.3)	73 (78.5)	29 (74.4)	0.006
ETV6-RUNX1	7 (5.3)	7 (7.5)	0 (0.0)
Hyperdiploidy	6 (4.5)	6 (6.5)	0 (0.0)
Others	17 (12.9)	7 (7.5)^a	10 (25.6)^b
*RAS* ^c
Wild-type	175 (74.5)	105 (70.0)	70 (82.4)	0.03
Mutated	60 (25.5)	45 (30.0)	15 (17.6)
*BRAF*
Wild-type	124 (99.2)	61 (100.0)	63 (98.4)	1.00
Mutated	1 (0.8)	0 (0.0)	1 (1.6)
*FLT3*
Wild-type	148 (93.1)	88 (91.7)	60 (95.2)	0.52
Mutated	11 (6.9)	8 (8.3)	3 (4.8)
*NQO1* (rs1800566) ^d
CC	97 (54.2)	67 (53.6)	30 (55.6)	0.91
CT	70 (39.1)	50 (40.0)	20 (37.0)
TT	12 (6.7)	8 (6.4)	4 (7.4)

^aFour pre-B ALL cases presenting the fusion transcript TCF3-PBX1, one pre-B ALL case presenting the cytogenetics t(2;14)(p10;q23), one pre-B ALL case presenting the cytogenetics t(5;15)(q12;q13) and one common ALL case presenting complex karyotype. ^bOne M4-AML presenting RUNX1-RUNX1T1 fusion transcript. Five M4-AML cases presenting CBFβ-MYH11 fusion transcript. One M3-AML presenting PML-RARa fusion transcript. One M0-AML, one M7-AML case and one AML case not otherwise specified presenting complex karyotype. AML subtypes according to FAB classification; ^cMutations in either KRAS or NRAS. ^dGenotype frequencies of NQO1 polymorphism. ALL: acute lymphoblastic leukaemia; AML: acute myeloid leukaemia; n: number of cases; WBC: white blood cell; MLL ^r: rearranged MLL.

ISSN: 1471-2407