Table 3.
Morphologic, Immunophenotypic and In Situ Hybridization Characteristics of Double-Hit Lymphoma Cases
| Case | WHO Classification |
Morphology | Features of pre-existing lymphoma (if applicable) |
Surface light chain* |
CD20 | Pax5/ CD79a |
CD10 | Bcl6 | Bcl2^ | Mum1 | TdT | Ki-67 (%) |
EBER |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | BCLU | Burkitt-like | FL, grade 1/3 (confirmed by morphology and FISH) |
Absent | ND | +/+ | + | − | + | + | − | 100 | − |
| 2 | BCLU | Burkitt-like | − | Lambda | + | +/+ | − | + (wk) | + | + | − | 80 | − |
| 3 | BCLU | Burkitt-like | − | Absent | + | +/+ | + | + | + ^ | − | − | 100 | − |
| 4 | BCLU | Burkitt-like | − | Lambda | + | +/+ | + | + | + | + (wk) | − | 65 | − |
| 5 | BCLU | Burkitt-like | − | Kappa | + | ND/+ | + | + (wk) | + | − | ND | 60 | ND |
| 6 | BCLU | Intermediate | − | Lambda | + | +/+ | + | + | + | − | − | 90 | − |
| 7 | BCLU | Intermediate | − | Lambda | + | +/+ | + | + (wk) | ND | + | − | 100 | − |
| 8 | BCLU | Intermediate | FL, grade 1-2 (confirmed by morphology and FISH) |
Lambda | + | ND/ND | + | + | ND | ND | ND | 25 | − |
| 9 | BCLU | Intermediate | − | Lambda | + | ND/+ | + | + | + | − | − | 95 | − |
| 10 | BCLU | Blastoid | GC-BCL, MYC+, BCL2x8, with high Ki-67 PI and blastoid morphology |
Kappa | + | ND/ND | + | ND | + | − | − | 80 | − |
| 11 | BCLU | Blastoid | GC-BCL with diffuse growth and blastoid morphology (FISH ND) |
Kappa | + | ND/+ | + | + | + | − | ND | 80 | − |
| 12 | BCLU | Blastoid | CHL (by report) | Lambda | + | +/ND | + | + | + | − | − | 70 | − |
| 13 | DLBCL | DLBCL | − | Lambda | + | +/+ | + | + | + | + (wk) | − | 90 | − |
| 14 | DLBCL | DLBCL | − | Lambda | + | +/+ | + | + | + | − | − | 80 | − |
| 15 | DLBCL | DLBCL | − | ND | + | +/ND | − | + | + | + (wk) | − | 80 | − |
| 16 | DLBCL | DLBCL | − | Lambda | + | +/+ | + | + | + | − | ND | 85 | − |
| 17 | DLBCL | DLBCL | − | Absent | + | ND/ND | + | + (wk) | + | + (wk) | − | 90 | − |
| 18 | DLBCL | DLBCL | FL, grade 1-2 (by report) | ND | + | +/ND | ND | + | + | − | − | 95 | − |
| 19 | DLBCL | DLBCL | FL, grade 1-2 (confirmed by morphology and FISH) |
Absent | + | +/ND | + | + (wk) | + | − | − | 80 | − |
| 20 | B-LBL | B-LBL | − | Absent | − | +/+ | + | − | + | + | + | 50 | − |
Surface light chain expression was determined by flow cytometry in each case.
All cases tested were Bcl2+ with clone 124 (targeting amino acids 41-54) except for case 3, which was subsequently tested using clone C-2 (targeting amino acids 1-205) and found to be positive.
BCLU: B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma, B -LBL: B-lymphoblastic lymphoma/leukemia, CHL: classical Hodgkin lymphoma, DLBCL: diffuse large B-cell lymphoma, not otherwise specified, EBER: Epstein-Barr virus encoded RNA, FISH: fluorescence in situ hybridization, FL: follicular lymphoma, GC-BCL: germinal center-phenotype B-cell lymphoma, ND: not done, PI: proliferation index, TdT: terminal deoxynucleotidyl-transferase, WHO: World Health Organization, wk: weak, +: positive, −: negative.