Table 2 Factors associated with progression-free-survival (PFS) and overall survival (OS) among A/MBC patients treated with Eribulin (univariate cox proportional-hazards analysis)

Demographic and clinical characteristics

 Age (years)

1.00 (0.97 – 1.03)

0.778

1.04 (1.00 – 1.07)

0.032

 Estrogen receptor (Negative vs. Positive)

1.12 (0.59 – 2.14)

0.727

0.87 (0.41 – 1.83)

0.714

 Progesterone receptor (Negative vs. Positive)

1.30 (0.68 – 2.46)

0.426

0.74 (0.36 – 1.55)

0.430

 HER2 status (Positive vs. Negative)

1.22 (0.63 – 2.37)

0.557

0.88 (0.43 – 1.82)

0.732

 TNBC (Yes vs. No)

0.97 (0.40 – 2.34)

0.947

1.12 (0.39 – 3.22)

0.840

 Number of metastatic site (> 1 vs. ≤1)

1.77 (0.82 – 3.82)

0.150

2.50 (1.02 -6.13)

0.045

Metastatic sites

 Non visceral metastasis

1

1

 Visceral and bone (2)

1.24 (0.61 – 2.54)

0.550

1.79 (0.81 – 4.00)

0.152

 Visceral only (3)

1.60 (0.57 – 4.49)

0.389

1.28 (0.43 – 3.81)

0.658

Eribulin line of therapy for recurrent and metastatic breast cancer (≥3^rd vs. <3^rd)

1.62 (0.76 – 3.46)

0.212

4.30 (1.30 – 14.22)

0.017

(Neo)adjuvant (No vs. Yes)

1.37 (0.53 – 3.49)

0.516

0.95 (0.34 – 2.64)

0.925

Monotherapy of eribulin (No vs. Yes)

0.97 (0.46 – 2.07)

0.945

1.03 (0.46 -2.32)

0.941

Still use eribulin or not at the time point of test as compare with that at baseline

 Off/on eribulin treatment at 1-month-test

0.99 (0.23 – 4.34)

0.988

4.21 (0.89 – 19.82)

0.069

 Off/on eribulin treatment at 3-month-test

4.43 (2.11 – 9.30)

<0.0001

0.99 (0.45 – 2.15)

0.973

 Off/on eribulin treatment at 6-month-test

4.04 (1.97 – 8.30)

<0.0001

1.921 (0.88 – 4.21)

0.103