Immunophenotypic features of pediatric follicular lymphoma.

(A) Immunohistochemistry for CD20 highlights the follicular architecture of this tumor. (B) The neoplastic cells of nearly all cases were positive for bcl-6. (C) Most of the cases manifested expanded networks of follicular dendritic cells as highlighted in this immunostain for CD21. (D) Immunostaining for bcl-2 reveals moderately intense expression of bcl-2 by neoplastic lymphoma cells within the nodules. Original magnification A, × 10; B, × 200; C-D, × 100; insets, × 400.