Survival Outcomes of Breast-Conserving Therapy versus Mastectomy in Early-Stage Breast Cancer, Including Centrally Located Breast Cancer: A SEER-Based Study

Table 4

Comparison of baseline characteristics between CLBC patients undergoing BCT and mastectomy from 2000 to 2015.

	Mastectomy		BCT		-value
	N	%	N	%
Year					0.063
2000–2003	1388	22.4%	1214	20.7%
2004–2007	1447	23.4%	1382	23.6%
2008–2015	3352	54.2%	3268	55.7%
Age, years					<0.001
18–63	3866	62.5%	3560	60.7%
64–72	1390	22.5%	1500	25.6%
73–79	931	15.0%	804	13.7%
Race					<0.001
White	4942	79.9%	4894	83.5%
Black	506	8.2%	485	8.3%
Others	739	11.9%	485	8.3%
Histological type					<0.001
IDC	5582	90.2%	5436	92.7%
ILC	605	9.8%	428	7.3%
Laterality					0.357
Left	3157	51.0%	2943	50.2%
Right	3030	49.0%	2921	49.8%
Grade
I	999	16.1%	1439	24.5%
II	2934	47.4%	2862	48.8%
III/IV	2254	36.4%	1563	26.7%
T stage					<0.001
T1a	415	6.7%	611	10.4%
T1b	770	12.4%	1400	23.9%
T1c	2179	35.2%	2521	43.0%
T2	2823	45.6%	1332	22.7%
N stage					<0.001
N0	3871	62.6%	4286	73.1%
N1	1860	30.1%	1350	23.0%
N2	310	5.0%	163	27.8%
N3	146	2.4%	65	1.1%
ER					<0.001
Negative	1025	16.6%	724	12.3%
Positive	5162	83.4%	5140	87.7%
PR					<0.001
Negative	1824	29.5%	1389	23.7%
Positive	4363	70.5%	4475	76.3%
Chemotherapy					<0.001
No or unknown	3451	55.8%	3476	59.3%
Yes	2736	44.2%	2388	40.7%

CLBC, centrally located breast cancer; BCT, breast-conserving therapy; IDC, invasive ductal carcinoma; ILC, invasive lobular carcinoma; ER, estrogen receptor; PR, progesterone receptor.