Table 2. Potential biomarkers.

Biomarker	Incidence	Prognostic or predictive	Method of testing	Possible clinical utility
TILs	N/A	Predictive	No standard testing	Identifies response to immunotherapy
Neoantigens	N/A	Predictive	Whole-exome RNA sequencing	Identifies response to immunotherapy
PD-1/PD-L1	N/A	Predictive	No standard testing	Identifies response to immunotherapy
CpG island methylation	40%	Predictive	Gene expression	Identifies response to alkylating agents

TILs, tumor-infiltrating lymphocytes; PD-1, programmed death protein-1; PD-L1, programmed death-ligand 1.