| Abstract: | ![]()
Predicting response of tumours to immune-oncology (IO) drugs targeting the programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) immune checkpoint is currently limited to assessing PD-L1 expression by immunohistochemistry (IHC). Much has been learned in the last few years about this uniquely challenging application of IHC and, in this short review, we assess its strengths and weaknesses, covering pre-analytics, analytics and post-analytics in the context of the complex underlying biology. In doing so, we hope to provide some practical guidance that will help optimize its application in routine practice. We also consider the crucial questions of quality control and speculate about how ongoing developments might assist in strengthening the power of anti-PD-L1 IHC as a predictor of response to IO drugs. |
