Prognostic significance of PD-L1 protein expression and copy number gains in locally advanced cervical cancer.

Background: Although immune checkpoint inhibitors against programmed death-1 (PD-1) and its ligand (PD-L1) have demonstrated promising results in several solid malignancies, including cervical cancer, there are some limitations to using PD-L1 immunohistochemical expression as a predictive biomarker for selecting patients who may benefit from such therapy.

Objective: To examine the protein expression and genetic status of PD-L1 with clinical outcomes in locally advanced cer- vical cancer.

Methods: We investigated the PD-L1 gene copy number gains assessed by fluorescence in situ hybridization (FISH) and PD-L1 expression using immunohistochemistry in 123 patients with locally advanced cervical cancers between December 2008 and December 2016.