{"denoms":[{"counts":[{"groupId":"OG000","value":"0"}],"units":"Participants"}],"description":"Mass spectrometry-based flow cytometric analysis (CyTOF) will be descriptive based on number and percentage of certain cell populations.","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":"Mass Spectrometry-based Flow Cytometric Analysis","type":"OTHER_PRE_SPECIFIED"}