Clinicopathologic and Prognostic Significance of Body Mass Index (BMI) among Breast Cancer Patients in Western China: A Retrospective Multicenter Cohort Based on Western China Clinical Cooperation Group (WCCCG)

Table 2

Clinicopathologic characteristic for premenopausal patients according to BMI (n=4,462).

Characteristics	BMI (kg/m2) (%)				P
	<18.5	18.5-24.9	≥25	Total
Tumor histology
Carcinoma in situ	4(1.8)	108(3.4)	29(2.7)	141(3.2)	0.26
Invasive carcinoma	215(95.6)	2930(92.2)	985(92.9)	4130(92.6)
Missing data	6(2.7)	139(4.4)	46(4.3)	191(4.3)
Histologic type
Ductal	187(83.1)	2514(79.1)	846(79.8)	3547(79.5)	0.12
Lobular	5(2.2)	54(1.7)	18(1.7)	77(1.7)
Medullary	4(1.8)	39(1.2)	24(2.3)	67(1.5)
Other	27(12.0)	526(16.6)	159(15.0)	712(16.0)
Missing data	2(0.9)	44(1.4)	13(1.2)	59(1.3)
Nuclear grade
I	8(3.6)	136(4.3)	27(2.5)	171(3.8)	0.09
II	76(33.8)	1092(34.3)	380(35.8)	1548(34.7)
III	31(13.8)	478(15.0)	179(16.9)	688(15.4)
Missing data	110(48.9)	1471(46.3)	474(44.7)	2055(46.1)
Lymphovascular-invasion
No	116(51.6)	1606(50.6)	515(48.6)	2237(50.1)	0.66
Yes	4(1.8)	88(2.8)	27(2.5)	119(2.7)
Missing data	105(46.7)	1483(46.7)	518(48.9)	2106(47.2)
No. of positive ALN
0	100(44.4)	1316(41.4)	422(39.8)	1838(41.2)	0.61
1-3	37(16.4)	558(17.6)	164(15.5)	759(17.0)
≥4	77(34.2)	1086(34.2)	373(35.2)	1536(34.4)
Missing data	11(4.9)	217(6.8)	101(9.5)	329(7.4)
ER
Negative	69(30.7)	851(26.8)	308(29.1)	1228(27.5)	0.25
Positive	117(52.0)	1702(53.6)	547(51.6)	2366(53.0)
Missing data	39(17.3)	624(19.6)	205(19.3)	868(19.5)
PR
Negative	70(31.1)	891(28.0)	329(31.0)	1290(28.9)	0.13
Positive	112(49.8)	1655(52.1)	523(49.3)	2290(51.3)
Missing data	43(19.1)	631(19.9)	208(19.6)	882(19.8)
HER2
Negative	76(33.8)	1273(40.1)	453(42.7)	1802(40.4)	0.25
Positive	25(11.1)	305(9.6)	98(9.2)	428(9.6)
Missing data	124(55.1)	1599(50.3)	509(48.0)	2232(50.0)
Tumor Subtypes
Luminal-like	57(25.3)	937(29.5)	311(29.3)	1305(29.2)	0.13
HER2/luminal-like	17(7.6)	187(5.9)	52(4.9)	256(5.7)
HER2-like	8(3.6)	116(3.7)	45(4.2)	169(3.8)
Triple negative	19(8.4)	328(10.3)	139(13.1)	486(10.9)
Missing data	124(55.1)	1609(50.6)	513(48.4)	2246(50.3)
Surgery
Non-surgery	1(0.4)	9(0.3)	7(0.7)	17(0.4)	<0.001
MRM	167(74.2)	2374(74.7)	853(80.5)	3394(76.1)
BCS	31(13.8)	391(12.3)	106(10.0)	528(11.8)
Other	21(9.3)	301(9.5)	63(5.9)	385(8.6)
Missing data	5(2.2)	102(3.2)	31(2.9)	138(3.1)
Chemotherapy
No	20(8.9)	326(10.3)	91(8.6)	437(9.8)	0.24
Yes	202(89.8)	2760(86.9)	940(88.7)	3902(87.4)
Missing data	3(1.3)	91(2,9)	29(2.7)	123(2.8)
Radiotherapy
No	175(77.8)	2400(75.5)	795(75.0)	3370(75.5)	0.80
Yes	45(20.0)	673(21.2)	230(21.7)	948(21.1)
Missing data	5(2.2)	104(3.3)	35(3.3)	144(3.2)
Endocrine therapy
No	163(72.4)	2236(70.4)	749(70.7)	3148(70.6)	0.92
Yes	57(25.3)	832(26.2)	276(26.0)	1165(26.1)
Missing data	5(2.2)	109(3.4)	35(3.3)	149(3.3)

ER, estrogen-receptor; PR, progesterone receptor; ALN, axillary lymph nodes; MRM, modified radical mastectomy; BCS, breast-conserving surgery.
Pearson χ2 test, except Fisher’s exact test.