Table 1 Demographic and clinical characteristics of patients based on pCR status

Age at Diagnosis (years, Mean ± SD, Median)

50.4 ± 12.4, 50.0

48.6 ± 10.3, 47.0

0.261^m

Gender (n, %)

 Female

179 (99.4%)

88 (98.9%)

0.553ˣ²

 Male

1 (0.6%)

1 (1.1%)

Menopausal Status (n, %)

 Premenopausal

93 (51.7%)

49 (55.1%)

0.600ˣ²

 Postmenopausal

87 (48.3%)

40 (44.9%)

ECOG Performance Score (n, %)

 0

166 (92.2%)

79 (88.8%)

0.349ˣ²

 I-II

14 (7.8%)

10 (11.2%)

 Ki67 at Diagnosis (≥ 50%) (Mean ± SD, Median)

59.6 ± 21.9, 60.0

66.0 ± 19.5, 70.0

0.030^m

BRCA Status (n, %)

 Negative

22 (59.5%)

15 (55.6%)

0.197ˣ²

 Positive

15 (40.5%)

12 (44.4%)

Inflammatory Breast Cancer (n, %)

 Negative

171 (95.0%)

89 (100.0%)

0.032ˣ²

 Positive

9 (5.0%)

0 (0.0%)

Histopathological Diagnosis (n, %)

 Invasive Carcinoma (Ductal/NST)

160 (88.9%)

79 (88.7%)

0.422ˣ²

 Invasive Lobular Carcinoma

6 (3.3%)

1 (1.1%)

 Others

14 (7.8%)

9 (10.1%)

Tumor Grade at Diagnosis (n, %)

 Grade 1

7 (3.9%)

3 (3.4%)

0.001ˣ²

 Grade 2

59 (32.8%)

11 (12.4%)

 Grade 3

114 (63.3%)

75 (84.3%)

HER2 Status Before Neoadjuvant Therapy (n, %)

 Negative (Score 0)

64 (35.6%)

53 (59.6%)

0.001ˣ²

 Negative (Score 1)

78 (43.3%)

27 (30.3%)

 Negative (Score 2, FISH Negative)

38 (21.1%)

9 (10.1%)

Clinical Tumor Stage (n, %)

 T1

2 (1.7%)

18 (20.2%)

0.063ˣ²

 T2

115 (63.9%)

58 (65.2%)

 T3

32 (17.8%)

10 (11.2%)

 T4a

5 (2.8%)

0 (0.0%)

 T4b

2 (1.1%)

3 (3.4%)

 T4d

5 (2.8%)

0 (0.0%)

Lymph Node Stage (n, %)

 N0

39 (21.7%)

28 (31.5%)

0.168ˣ²

 N1

99 (55.0%)

48 (53.9%)

 N2

31 (17.2%)

11 (12.4%)

 N3

11 (6.1%)

2 (2.2%)

Clinical Stage (n, %)

 1B

5 (2.8%)

5 (5.6%)

0.101ˣ²

 2A

3 (1.7%)

0 (0.0%)

 2B

43 (23.9%)

29 (32.6%)

 3B

77 (42.8%)

36 (40.4%)

 3 C

52 (28.9%)

19 (21.3%)

HER2 Status (n, %)

 HER2-zero

64 (35.6%)

53 (59.6%)

 < 0.001ˣ²

 HER2-low

116 (64.4%)

36 (40.4%)

Carboplatin (n, %)

 Non-Recipient

145 (80.6%)

56 (62.9%)

0.002ˣ²

 Recipient

35 (19.4%)

33 (37.1%)