Cancer-immune expressional variation in glioblastoma second surgery samples to compare progression and pseudoprogression

We performed cancer-immune gene expression analysis on a case series of glioblastoma second surgery samples due to novel enhancement following chemoradiation that were confirmed based on clinico-pathologic outcome as disease progression (PD) or pseudoprogression (psPD). This was accomplished using an nCounter Pancancer 360 IO panel. Our goals were to (1) determine if psPD events could be distinguished from PD events using differences in immune cell activation versus cancer cell proliferation and (2) examine whether samples stratified based on their molecular profile in the same way as documented clinico-pathologic diagnosis. NanoString nCounter pancancer 360 IO panel testing was performed on 48 glioblastoma samples with 27 showing progression (PD) and 21 showing pseudoprogression (psPD) taken from brain resection at second surgery. Sample designation was based upon clinico-pathologic correlation from the electronic health record.