Table 3 Univariate and multivariate analyses of progression-free survival in validation cohort treated with letrozole and palbociclib

Age

 ≥ 65 years old

0.725 (0.533–0.985)

0.710 (0.522–0.966)

 < 65 years old

Reference

Reference

Race

 White

Reference

 Others

0.931 (0.649–1.337)

ECOG performance status

 0

Reference

 1, 2

1.280 (0.958–1.710)

Initial stage

 III–IV

1.176 (0.881–1.570)

 Others

Reference

Recurrence type

 Newly diagnosed

0.952 (0.694–1.306)

 Others

Reference

Disease-free interval

 Newly metastatic disease

0.879 (0.653–1.185)

 Others

Reference

Disease site

 Visceral

1.838 (1.369–2.468)

1.661 (1.172–2.355)

 Nonvisceral

Reference

Reference

Bone-only metastasis

 Bone-only metastasis

0.601 (0.412–0.877)

0.763 (0.486–1.197)

 Others

Reference

Reference

Number of disease sites

 ≥ 3

1.265 (0.947–1.690)

 1, 2

Reference

Derived neutrophil-to-lymphocyte ratio^a

 ≥ 1.04

1.498 (1.102–2.037)

1.563 (1.148–2.129)

 < 1.04

Reference

Reference