THRLBCL-like cases (case 13 [A-C,G,H,J-L], case 11 [D-F], and case 16 [I]). (A) The lymph node shows effacement of the architecture. (B) Scattered mono- or multilobated tumor cells, some HRS-like, are observed in a lymphohistiocytic microenvironment. (C) Bone marrow biopsy shows similar morphology. (D) Case 11 shows a diffuse proliferation, rich in histiocytes with sparse tumor cells, morphologically indistinguishable from THRLBCL. (E) Foci of necrosis are present. (F) The tumor cells are positive for CD20, with rare small B cells in the background. Most cases expressed CD79a (G), CD30 (H), PD-L1 (I), LMP1 (J), and EBER (K). (L) Numerous dendritic cells/histiocytes IDO positive are present in the microenvironment. Original magnifications: ×40 (A), ×100 (E), ×200 (D,F), and ×400 (B,C,D inset, G-L).