TREM2 and neoplasm: Importantly, unlike the TREM2 myeloid cell signature, the 16-gene BIT-associated TREM1 myeloid signature was specifically enriched in BIT regions spatially (Figs. 5d–f, Supplementary Fig. 5e), reinforcing the spatial association between BIT tumor epithelium and the specialized TREM1 myeloid cell-associated inflammatory environment.