Cause of death for patients with breast cancer: discordance between death certificates and medical files, and impact on survival estimates

Table 1 General patient and tumor characteristics (n = 2,862)

Category	Subgroups	N of patients	(%)
Age at time of diagnosis	<40 years	188	6,6
	40-49	562	19,6
	50-59	778	27,2
	60-69	709	24,8
	70-79	423	14,8
	≥80	202	7,1
Year of diagnosis	2009	489	17,1
	2010	448	15,7
	2011	468	16,4
	2012	483	16,9
	2013	500	17,5
	2014	474	16,6
Stage at diagnosis	Stage 0	47	1,6
	Stage I	1063	37,1
	Stage II	1174	41,0
	Stage III	357	12,5
	Stage IV	158	5,5
	Stage unknown	63	2,2
Tumor Grade	Grade 1	319	11,1
	Grade 2	1378	48,1
	Grade 3	1126	39,3
	Grade unknown	39	1,4
Multiple tumors	No	2733	95,5
Multiple tumors	2+	129	4,5
Treatment^a	Breast Conserving Surgery	1374	48,0
	Mastectomy	1311	45,8
	Radiotherapy	2354	82,3
	Chemotherapy	1296	45,3
	Hormonal therapy	2344	81,9
Morphology	Ductal	2118	74,0
	Lobular	337	11,8
	Other	407	14,2

^aSome patients receive multiple different treatment interventions within each subgroup (surgery or systemic therapy) during their follow-up period

ISSN: 2049-3258