Differences in breast tumor response to neoadjuvant chemotherapy by race – Is obesity the key?

Figures & data

Table 1. Demographic and clinicopathological characteristics summary by race.

Variable	White (n = 779)	Black (n = 103)	Total (n = 882)	P-value
Age at diagnosis, median [IQR]	51 [41, 59]	51 [42, 60]	51 [41, 59]	0.850
Ethnicity				0.415
Hispanic	5 (1%)	0 (0%)	5 (1%)
Non Hispanic	774 (99%)	103 (100%)	877 (99%)
BMI, Median [IQR]	28.4 [24.3, 34]	31.5 [26.7, 35.2]	28.6 [24.5, 34.4]	0.001*
BMI				0.002*
BMI <30	454 (58%)	43 (42%)	497 (56%)
BMI ≥30	325 (42%)	60 (58%)	385 (44%)
Employment status				0.024
Missing	1 (0%)	0 (0%)	1 (0%)
Employed	645 (83%)	76 (74%)	721 (82%)
Unemployed	133 (17%)	27 (26%)	160 (18%)
Insurance status				<0.001*
Missing	1 (0%)	0 (0%)	1 (0%)
Private	595 (76%)	40 (39%)	635 (72%)
Public	163 (21%)	47 (46%)	210 (24%)
Uninsured	20 (3%)	16 (16%)	36 (4%)
Menopausal status				0.676
Premenopausal	351 (45%)	42 (41%)	393 (45%)
Postmenopausal	380 (49%)	55 (53%)	435 (49%)
Unknown	48 (6%)	6 (6%)	54 (6%)
Grade				0.189
High grade	456 (59%)	69 (67%)	525 (60%)
Intermediate grade	241 (31%)	27 (26%)	268 (30%)
Low grade	37 (5%)	1 (1%)	38 (4%)
Unknown	45 (6%)	6 (6%)	51 (6%)
Stage				0.399
1	109 (14%)	13 (13%)	122 (14%)
2	504 (65%)	62 (60%)	566 (64%)
3	166 (21%)	28 (27%)	194 (22%)
ER status				0.086
Negative	376 (48%)	59 (57%)	435 (49%)
Positive	403 (52%)	44 (43%)	447 (51%)
PR status				0.101
Negative	464 (60%)	70 (68%)	534 (61%)
Positive	315 (40%)	33 (32%)	348 (39%)
HER2 status				0.070
Negative	291 (37%)	48 (47%)	339 (38%)
Positive	488 (63%)	55 (53%)	543 (62%)
Subtype				0.061
ER+/PR+/HER2- & ER+/PR-/HER2-	122 (16%)	17 (17%)	139 (15%)
ER-/PR-/HER2-	164 (21%)	31 (30%)	195 (22%)
HER2+	493 (63%)	55 (53%)	548 (62%)
Pathological complete response				0.962
No	520 (67%)	69 (67%)	589 (67%)
Yes	259 (33%)	34 (33%)	293 (33%)

Abbreviations: BMI, body mass index; ER status, estrogen receptor status; PR status, progesterone receptor status; HER2, human epidermal growth factor receptor 2.

*Indicates statistical significance at p < 0.05.

Table 2. Univariable and multivariable predictors for pathological complete response.

Patient characteristic	Univariable analysis			Multivariable analysis
	OR	95% CI	P value	OR	95% CI	P value
Age at diagnosis
< 40 years old vs ≥ 40 years old (ref)	1.6	(1.1, 2.2)	0.011*	1.6	(1.1, 2.4)	0.012*
Race
White vs Black (ref)	1.0	(0.7, 1.6)	0.961	1.0	(0.6, 1.6)	0.921
BMI
BMI < 30 vs BMI ≥ 30 (ref)	1.1	(0.9, 1.5)	0.395	1.1	(0.8, 1.5)	0.522
Menopausal status
Postmenopausal vs Premenopausal (ref)	0.9	(0.7, 1.2)	0.608	1.1	(0.8, 1.5)	0.563
Insurance status
Public vs Private (ref)	0.9	(0.7, 1.3)	0.601	1.0	(0.7, 1.4)	0.956
Uninsured vs Private (ref)	1.3	(0.6, 2.5)	0.498	1.4	(0.7, 2.8)	0.413
Employment status
Employed vs Unemployed (ref)	1.2	(0.9, 1.8)	0.264	1.3	(0.9, 1.9)	0.225

Abbreviations: OR, odds ratio; BMI, body mass index.

*Indicates statistical significance at p < 0.05.

Data availability statement

The data that support the findings of this study are available on request from the corresponding author, [RR]. The data are not publicly available due to their containing information that could compromise the privacy of research participants.