Main characteristic of 6 eligible studies enrolled in this meta-analysis.

Abstract

<p><i>NR</i> data were not reported, <i>NS</i> not significant, <i>ISH</i> in situ hybridization, <i>IHC</i> immunohistochemistry,</p>a<p>directly extracted from original data,</p>b<p>extrapolated from survival curve.</p