PAX5 and B-cell chronic lymphocytic leukemia: The pathological diagnosis was the transformation from CLL/SLL to HL. Immunohistochemistry (Figure 1) revealed that Hodgkin-like cells were positive for CD30, CD20, CD79a, PAX-5 (weak), MUM-1, C-MYC, BCL6 (partially), and BCL-2; Ki-67 was approximately 60%; and EBV-encoded RNA was positive.