Table 1.
Pathologic features differentiating PEL from other aggressive lymphomas
| DLBCL immunoblastic variant | PBL | ALCL | PEL | |
|---|---|---|---|---|
| Morphology | Diffuse sheets of large cells with prominent nucleoli and abundant cytoplasm, with plasmacytoid features | Diffuse large cells with abundant cytoplasm and eccentrically placed nuclei and smaller nucleoli resembling plasma cells | Pleomorphic nuclei with multiple (or single) prominent nucleoli with abundant cytoplasm | Variable morphology between large immunoblastic, plasmablastic or anaplastic large cell lymphoma |
| EBV positivity | 90%–100% | >50% | Negative | 60%–90% |
| HHV8 positivity | – | – | – | 100% |
| Phenotype | BCL6−, CD138+, MUM1+ | CD38+, CD138+, CD20− | CD30+, EMA+, CD4+, CD2+, TIA, Granzyme or Perforin+ | CD30+, CD38+, CD138+, CD45+ |
| Cellular origin | Mostly GC or post-GC B cells | Post-GC cells | Primitive T-cell origin | GC or post-GC B cells |
Abbreviations: PEL, primary effusion lymphoma; EBV, Epstein Bar virus; HHV8, human herpes virus 8; GC, germinal center; DLBCL, diffuse large B cell lymphoma; PBL, plasmablastic lymphoma; ALCL, anaplastic large cell lymphoma.