CD8A and hemophagocytic syndrome: Although EBV+ HLH, sCAEBV, and sEBV+ TCL are difficult to differentiate, and may be serial diseases, the rapidly progressive clinical course, HLH, CD8+ atypical lymphocytes with overt nuclear atypia, TCR gene rearrangements, and therapy resistance were important findings for making the diagnosis of sEBV+ TCL.