{"denoms":[{"counts":[{"groupId":"OG000","value":"0"}],"units":"Participants"}],"description":"Other immune escape mechanisms including MDSCs and other checkpoints will be assessed by immunohistochemistry (0 - 3+) or flow cytometry counting the number and percentage of positive cells. Levels will be correlated with PD-L1 expression and other biomarkers.","groups":[{"description":"Patients receive pembrolizumab IV over 30 minutes on day 1. Treatment repeats every 21 days for up to 24 months in the absence of disease progression or unacceptable toxicity. Patients may be eligible for up to 1 year of additional pembrolizumab therapy if they progress after stopping pembrolizumab.\n\nPembrolizumab: Given IV\n\nLaboratory Biomarker Analysis: Correlative studies\n\nPharmacogenomic Study: Correlative studies","id":"OG000","title":"Treatment (Pembrolizumab)"}],"populationDescription":"Exploratory endpoint. Data not collected.","reportingStatus":"POSTED","timeFrame":"Up to 5 years","title":"Composite Measure of Other Immune Escape Mechanisms Including MDSCs and Other Checkpoints","type":"OTHER_PRE_SPECIFIED"}