Table 4. Risk of breast cancer-specific death according to treatment among non-carriers and BRCA2 carriers (period of diagnosis 1980–2012), multivariatea.

	Non-carriers					BRCA2 mutation
	Patients (n=369)	Deaths (n=71)	HR	95% CI	P-value	Patients (n=187)	Deaths (n=71)	HR	95% CI	P-value	P-value interactionb
Surgery											0.007
Lumpectomy	153	26	1			49	14	1
Mastectomy	214	62	1.01	0.51–2.03	0.97	138	57	0.49	0.21–1.11	0.09
Adjuvant chemotherapy											0.06
None	185	35	1			82	31	1
Any	175	50	0.98	0.47–2.04	0.96	101	40	0.35	0.16–0.80	0.01
Anthracyclin	81	15	1.41	0.54–3.69	0.48	51	15	0.36	0.13–0.98	0.05
Nonanthracyclin	94	35	0.84	0.38–1.86	0.67	49	24	0.34	0.14–0.83	0.02
Radiation											0.13
None	167	41	1			86	31	1
Any	198	47	0.87	0.48–1.56	0.64	98	40	1.09	0.59–2.04	0.78
Adjuvant hormone therapy											0.16
None	206	64	1			94	36	1
Any	154	22	0.65	0.32–1.33	0.24	89	35	1.03	0.41–2.60	0.95

Abbreviations: CI=confidence interval; HR=hazard ratio.

^aModel including year of birth, year of diagnosis, size, nodal status, grade, ER status and all other treatment categories.

^bInteraction between BRCA2 mutation status and the relevant variable.