EGFR and neoplasm: Therefore, studies mimicking in-patient and back-table (ex vivo) intraoperative assessment strategies [2] were undertaken to compare PAI and SAI to gold standard tumor delineation techniques using H&E and EGFR immune-stained formalin-fixed paraffin-embedded pathology, with co-registration to PAI and SAI and correlation on a pixel-to-pixel basis (Fig. 3).