BOB.1, CD79a and cyclin E are the most appropriate markers to discriminate classical Hodgkin's lymphoma from primary mediastinal large B-cell lymphoma.
OBJECTIVE
To clarify which immunohistochemical markers could be helpful in distinguishing between classical Hodgkin's lymphoma (cHL) and primary mediastinal B-cell lymphoma (PMBCL) to more narrowly define 'B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and cHL'.


RESULTS
Two hundred and 83 cHLs and 51 PMBCLs were analysed on validated tissue microarray platforms with antibodies to BOB.1, CD15, CD20, CD23, CD30, CD79a, cyclin E, LMP-1, MUM1p, p63 and Oct2. The marker cut-off scores were calculated using receiver-operating characteristic curves. Markers with the highest positive predictive value for cHL were: CD15, cyclin E, LMP-1 (all 100%), MUM1p (93%) and CD30 (83%). High sensitivity was achieved only by CD30 (92%) and cyclin E (79%). Nineteen percent of PMBCLs were also positive for CD30, which led to a lower specificity of CD30 as regards cHL (81%) compared with cyclin E (100%). The antibodies with the highest positive predictive value for PMBCL were: CD23 (98%), p63 (96%), BOB.1 (94%) and CD79a (90%), with high sensitivity for BOB.1 (100%), CD79a (89%) and p63 (82%).


CONCLUSIONS
The use of at least three of the most accurate immunohistochemical markers, cyclin E, CD79a and BOB.1, may be helpful in the differential diagnosis of cHL and PMBCL.
Hoeller
Sylvia
S
Department of Pathology, University of Basel, Basel, Switzerland.
Zihler
Deborah
D
Zlobec
Inti
I
Obermann
Ellen C
EC
Pileri
Stefano A
SA
Dirnhofer
Stephan
S
Tzankov
Alexandar
A
D000912:Antibodies, Neoplasm / Q000276:immunology; D014408:Biomarkers, Tumor; D051925:CD79 Antigens / Q000032:analysis* / Q000276:immunology; D019927:Cyclin E / Q000032:analysis* / Q000276:immunology; D003937:Diagnosis, Differential; D006689:Hodgkin Disease / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D011237:Predictive Value of Tests; D012372:ROC Curve; D015534:Trans-Activators / Q000032:analysis* / Q000276:immunology
D000912:Antibodies, Neoplasm; D014408:Biomarkers, Tumor; D051925:CD79 Antigens; D019927:Cyclin E; C091546:POU2AF1 protein, human; D015534:Trans-Activators