GZL (case 43). (A) The lymph node architecture is altered by nodular proliferation divided by collagen bands. (B) Sheets of large cells resembling HRS cells and variants—admixed with small lymphocytes, eosinophils, and granulocytes—are identified. (C) Foci of necrosis are present. The tumor cells are strongly and uniformly positive for CD20 (D), PAX5 (E), and Oct-2 (F). They are also positive for CD30 (G), CD15 (H), LMP1 (I), and EBER (J). Original magnifications: ×40 (A); ×200 (C), and ×400 (B,D-J).