Microphotographs of diagnostic PEL ascites and post BV-treated gastric biopsy from patient B. Initial peritoneal fluid contained numerous large atypical lymphoid cells with irregular nuclear contours and conspicuous nucleoli (A; Diff-Quik, original magnification ×500) with immunohistochemistry demonstrating expression of KSHV by LANA (B; original magnification ×400), and CD30 (C; original magnification ×400). The new gastric mass occurring posttreatment with BV (D; hematoxylin and eosin, original magnification ×400) showed sheets of similar atypical large lymphoid cells expressing KSHV (E; original magnification ×400) but without expression of CD30 (F; original magnification ×400).