Results of studies. (a) Hematoxylin and eosin staining (original magnification, ×400). (b) Immunohistochemical detection of CD79α (original magnification, ×400). (c) Double staining with periodic acid-Schiff stain (histochemistry) and paired box protein 5 (PAX5) (immunohistochemistry). (d) Electron microscopic micrograph of inclusion (original magnification, ×7,250). (e) Lane 1 is immunoglobulin heavy chain (IGH) rearrangements, lane 4 is immunoglobulin light chain kappa (IGK) rearrangements and lane 3 is a 50bp ladder.