KSHV is the causative agent of Kaposi sarcoma,1,2 two human lymphoproliferative diseases, primary effusion lymphoma (PEL),3,4 acquired immune deficiency syndrome (AIDS)-related multicentric Castleman disease,5,6 and a more recently described interleukin-6-related disease, KSHV-inflammatory cytokine syndrome.7 This evidence concerns the gene IL6 and primary effusion lymphoma.