TABLE 1.

Characteristics of the entire population, and by age group

Characteristic	Total population		<40		40 – 49		50 – 59		60 – 69		70 – 79		≥80		p value*
	N=2996		N=141		N=704		N=887		N=727		N=426		N=111
	n	%	n	%	n	%	n	%	n	%	n	%	n	%
Presentation
Clinical	386	13	43	30	99	14	91	10	83	11	52	12	18	16	<0.0001
Radiological	2606	87	98	70	605	86	795	90	644	89	371	87	93	84
Unknown	4	0	0	0	0	0	1	0	0	0	3	1	0	0
Family History
No	1816	61	84	60	427	61	522	59	452	62	264	62	67	60	0.7
Yes	1163	39	54	38	266	38	358	40	262	36	154	36	42	38
Unknown	44	1	3	2	11	2	7	1	13	2	8	2	2	2
Nuclear Grade
Low/intermediate	1787	60	82	58	420	60	543	61	422	58	259	61	61	55	0.4
High	994	33	47	33	235	33	287	32	259	36	124	29	42	38
Unknown	215	7	12	9	49	7	57	6	46	6	43	10	8	7
Necrosis
Absent	1029	34	46	33	270	38	308	35	228	31	139	33	38	34	0.1
Present	1802	60	84	60	395	56	533	60	465	64	256	60	69	62
Unknown	165	6	11	8	39	6	46	5	34	5	31	7	4	4
Number of excisions
≤2	2775	93	130	92	634	90	820	92	676	93	406	95	109	98	0.01
≥3	217	7	11	8	67	10	67	8	50	7	20	5	2	2
Unknown	4	0	0	0	3	0	0	0	1	0	0	0	0	0
Margin status
Close/positive	553	19	27	19	119	17	147	16	128	18	99	23	33	30	0.0003
Negative	2235	75	100	71	549	78	689	77	543	74	285	67	69	62
Unknown	208	7	14	10	36	5	51	6	56	8	42	10	9	8
Radiation therapy
Yes	1588	53	82	58	404	57	520	59	411	57	157	37	14	13	<0.0001
No	1374	46	56	40	294	42	358	40	309	43	263	62	94	85
Unknown	34	1	3	2	6	1	9	1	7	1	6	1	3	3
Endocrine therapy
Yes	628	21	16	11	145	21	238	27	158	22	63	15	8	7	<0.0001
No	2321	77	122	87	553	79	636	72	556	76	356	84	98	88
Unknown	47	2	3	2	6	1	13	1	13	2	7	2	5	5
Year of surgery
≤1998	785	26	56	40	181	26	214	24	179	25	128	30	27	24	0.0014
≥1999	2211	74	85	60	523	74	673	76	548	75	298	70	84	76

^*χ2 test of difference between age at time surgery