In this video, you will learn the basics of PD-L1 immunohisotchemistry interpretation, as applicable to the 22C3 antibody used for non-small cell lung carcinoma. Dr. Sanjay Mukhopadhyay is a medical doctor (pathologist) who diagnoses lung diseases such as lung cancer, mesothelioma, infections and interstitial lung disease by examining tissue samples with a microscope. He is the author of a textbook of lung pathology published by Cambridge University Press. He also posts freely accessible educational material related to pathology and lung diseases on Twitter (@smlungpathguy), Instagram (@smlungpathguy) and Facebook (his professional Facebook page is open to all). If you found this video to be useful, please like, comment, subscribe and share with your friends.