Comprehensive analysis of the ATM, CHEK2 and ERBB2genes in relation to breast tumour characteristics and survival: a population-based case-control and follow-up study

Table 1 Characteristics of the breast cancer cases in the parent study and the present genetic study

	Parent study	Present study	Present study
Characteristic	n (%)	n (%)	Breast cancer deaths^a	Mortality rate^b
Total cases	2,817	1,579	198	0.016
Tumour size (mm)
≤20	1,858 (71.4)	1,087 (73.6)	100	0.010
21–30	489 (18.8)	270 (18.3)	57	0.026
>30	254 (9.8)	120 (8.1)	38	0.043
Unknown	216	102	3	0.022
P value^c		0.13
TNM stage
1	1,392 (54.4)	804 (55.3)	40	0.006
2	1,074 (42.0)	606 (41.7)	126	0.026
3	58 (2.3)	31 (2.1)	15	0.076
4	34 (1.3)	12 (0.8)	11	0.262
Unknown	259	126	6	0.019
P value^c		0.39
Lymph-node involvement
No	1,741 (68.2)	1,002 (68.9)	68	0.008
Yes	813 (31.8)	453 (31.1)	122	0.035
Unknown	263	124	8	0.027
P value^c		0.23
Grade
1	259 (14.7)	143 (14.2)	4	0.003
2	739 (41.9)	444 (44.1)	37	0.010
3	766 (43.4)	419 (41.7)	93	0.027
Unknown	1,053	573	64	0.016
P value^c		0.61
Oestrogen and progesterone receptor status
ER⁺/PR⁺	1,162 (62.7)	677 (65.4)	72	0.012
ER⁺/PR-	285 (15.4)	133 (12.9)	28	0.026
ER-/PR⁺	69 (3.7)	33 (3.2)	7	0.027
ER-/PR-	338 (18.2)	192 (18.6)	52	0.037
Unknown	963	544	39	0.010
P value^c		0.37
Histological type
Ductal	1,891 (72.5)	1,070 (72.4)	147	0.016
Lobular	304 (11.7)	185 (12.5)	19	0.012
Other	414 (15.9)	223 (15.1)	28	0.014
Unknown	208	101	4	0.039
P value^c		0.48
S-phase fraction
Low	689 (68.1)	401 (70.0)	40	0.011
High	323 (31.9)	172 (30.0)	52	0.040
Unknown	1805	1,006	106	0.013
P value^c		0.71

^aFrom the date of diagnosis until 31 December 2003.
^bFrom the date of diagnosis until 31 December 2003 or until the date of death or emigration, whichever came first. Calculated as breast cancer deaths per person-year of follow-up.
^cChi-squared test of independence between the parent and the present studies.
ER, oestrogen receptor; PR, progesterone receptor

ISSN: 1465-542X