GZMB and posterior cortical atrophy: We found that HGG PCa was significantly more likely than low Gleason Grade (LGG; Gleason grade ≤ 4+3) PCa to contain immune cell clusters (ICs) with three key features of a spatially organized antitumor immune responses: (i) dense TILs comprising B and T cells (in different proportions); (ii) proliferating B cells and progenitor exhausted T cells (TPEX) within the cores of these infiltrates; and (iii) granzyme-B positive (GZB+) cytotoxic T cells in contact with tumor cells.