High mammographic breast density predicts locoregional recurrence after modified radical mastectomy for invasive breast cancer: a case-control study

Table 1 Characteristics between patients who did or did not experience recurrences

	Control group		Case group
	n = 121	Percentage	n = 121	Percentage	P value
Age (years)
mean (range)	51.4 (28–89)		51.6 (27–94)		0.738*
<40	15	12.4	19	15.7	0.725^†
40–59	87	71.9	82	67.8
>60	19	15.7	20	16.5
AJCC stage (pathological)
I	24	19.8	24	19.8	1.000^†
IIA	33	27.3	33	27.3
IIB	18	14.9	18	14.9
IIIA	20	16.5	20	16.5
IIIB	2	1.7	2	1.7
IIIC	24	19.8	24	19.8
Tumor size (mm)
0–10	19	15.7	19	15.7	0.911^†
10 − 19	19	15.7	22	18.2
20 − 50	68	56.2	63	52.1
>50	15	12.4	17	14.0
Positive axillary nodes
None	47	38.8	49	40.5	0.956^†
1–3	32	26.4	32	26.4
>4	42	34.7	40	33.1
Margin
Negative	112	92.6	106	87.6	0.197
Positive	9	7.4	15	12.4
Estrogen/progesterone receptor status
Negative	46	38.0	44	36.4	0.790^†
Positive	75	62.0	77	63.6
Her2 status^a
Negative	92	76.0	88	72.7	0.556
Positive	29	24.0	33	27.3
Triple-negative cancer
Negative	100	82.6	95	78.5	0.417
Positive	21	17.4	26	21.5
MBD quartiles
1 (0–25%)	29	24.0	10	8.3	0.023^†
2 (25–50%)	53	43.8	59	48.8
3 (50–75%)	32	26.4	41	33.9
4 (75–100%)	7	5.8	11	9.1
Adjuvant chemotherapy
No	26	21.5	21	17.4	0.417^†
Yes	95	78.5	100	82.6
Adjuvant hormone therapy
No	47	38.8	50	41.3	0.694^†
Yes	74	61.2	71	58.7
Adjuvant target therapy
No	100	82.6	102	84.3	0.729^†
Yes	21	17.4	19	15.7
Adjuvant radiotherapy
No	59	48.8	64	52.9	0.520^†
Yes	62	51.2	57	47.1
BMI (kg/m²)
mean (range)	24.0 (16.2–35.4)		23.1 (15.4–38.1)		0.272*
Normal (<25)	85	70.2	80	64.5	0.627^†
Overweight (25–30)	28	23.1	33	27.3
Obese (>30)	8	6.6	10	8.3

^a Human epidermal growth factor receptor 2 (Her2) status indicated all Her2 (3+)-positive tumors and Her2 (2+)- positive tumors with Her2 amplification investigated by fluorescence in situ hybridization; ratio ≥ 2. AJCC American Joint Committee on Cancer, MBD mammographic breast density, BMI body mass index. *Significance tested using paired Student’s t test. ^†Significance tested using Pearson’s chi-square test

ISSN: 1465-542X