Cases 19, 7, and 8.

(A) and (B): A lymph node from case 19 shows features of plasma cell variant CD (panels A and B). (A) Follicle comprises a hyalinized germinal center surrounded by a broad mantle. (B) High magnifcation showing uniform population of small lymphocytes in the mantle zone. (C) and (D): A lymph node from case 7, an HIV-positive patient, shows features of plasmablastic variant CD. (C) The follicle comprises a partially hyalinized germinal center surrounded by a well-formed mantle. (D) High magnification of mantle zone showing small lymphocytes and scattered transformed plasmablasts, 2 of which are arrowed. (E) and (F): A lymph node from case 8, an HIV-positive patient with plasmablastic CD. (E) The follicle shows a poorly defined mantle zone that is partially replaced by a concentric infiltrate of plasmablasts. (F) High magnification of area within the rectangle in Figure 1E, showing the germinal center (GC) surrounded by plasmablasts that have replaced the mantle. Some cells in mitosis are highlighted in squares.