In an age where the average American spends between two and three hours on the internet per day, it should come as no surprise that at least one of those hours per week is usually spent looking for health information. When websites such as WebMD or the Mayo Clinic provide descriptions of common symptoms for various diseases and conditions, Americans have decided that there is no longer any need for a medical degree to be able to diagnose them, they can play doctor themselves through a quick Google search.
As immuno-oncology agents are flooding the US market and invading earlier lines of treatment, pharmaceutical companies are working feverishly to develop companion diagnostic assays that qualify an ever-growing number of patients for these ground- braking drugs. However, the multitude of PD-L1 assays combined with the dynamic nature of the PD-L1 marker raise (thus far) unanswered questions around PD-L1 testing.