PTGS2 and neoplasm: The NOS2/COX2 expressions in ER- tumors previously scored as NOS2/COX2 high (hi) or low (lo) by routine immunohistochemistry (IHC) grades of 1–4 [7, 9] were analyzed for NOS2/COX2 fluorescence intensity at the single cell level using multiplexed fluorescence imaging, which provides spatial information at the single-cell level in regions including necrosis, stroma, and viable tumor.