Table 2.
Comparison of clinicopathological features of 22 cases with IRF4 rearrangements
| Clinicopathological features |
LBCL-IRF4 in patients < 25 years (6 cases) | LBCL-IRF4 in patients > 25 years (9 cases) | Aggressive lymphomas with IRF4 (7 cases) |
|---|---|---|---|
| Age |
Median 8 years (range 6–25 years) |
Median 69 years (range 37–87 years) |
Median 75 years (range 14–92 years) |
| Sex | M:F 2.5:1 | M:F 3.5:1 | M:F 2.5:1 |
| Localization | |||
| -Tonsils | 4 cases (57%) | 2 cases (22%) | 3 cases (43%) |
| -Lymph nodes | 1 case (14%) | 5 cases (56%) | 2 cases (29%) |
| -Intestine | 1 case (14%) | – | 1 case (14%) soft |
| -others | 1 case, (14%) spleen |
1 case (11%) soft tissue 1 case (11%) oral lesion* |
tissue 1 case (14%) testis |
| Clinical stage | |||
| - Stage 1/2 | 7 cases (100%) | 5 cases (56%) | 2 cases (29%) |
| - Stage 3/4 | 0 | 4 cases (44%) | 5 cases (71%) |
| Growth pattern | |||
| -Follicular | 2/6 case (33%) | 3 cases (33%) | 1 case (14%) (FL3A) |
| -Follicular/diffuse | 2/6 cases (33%) | 0 | 0 |
| -Diffuse | 2/6 cases (33%) | 6 cases (67%) | 6 cases (86%) |
| Immunophenotype | |||
| -MUM1 | 7 cases (100%) | 9 cases (100%) | 7 cases (100%) |
| -CD10 | 6 cases (86%) | 7 cases (78%) | 6 cases (86%) |
| -BCL6 | 7cases (100%) | 9 cases (100%) | 6 cases (86%) |
| -BCL2 | 6 cases (86%) | 2 cases (22%) | 5 cases (71%) |
| -CD5 | 3 cases (43%) | 0 cases (0%) | 1 case (14%) |
| FISH BAP | |||
| -IRF4 | 5/6 (83%)§ | 9 cases (100%) | 7 cases (100%) |
| -MYC | 0 | 0 | 2 cases (29%) |
| -BCL2 | 0 | 0 | 4 cases (57%) |
| -BCL6 | 0 | 1 case (11%) | 0 |
| -CCND1 | 0 | 0 | 1 case (14%) |
| Mutational profile | |||
| -IRF4 | 4/5 cases# (80%) | 4/5 cases (80%) | 1/4 case (25%)** |
| -TP53 | 3/5 cases | 0 | 0 |
| GEP | |||
| -GCB | 4/4 cases (100%) | 4/4 cases (100%) | 4 cases (57%) |
| -ABC | 0 | 0 | 3 cases (43%) |
LBCL-IRF4 large B-cell lymphoma with IRF4 rearrangement, BAP break apart probe, FISH fluorescence in situ hybridization, GEP gene expression profile, GCB germinal center B-cell, ABC activated B-cell, FL3A follicular lymphoma grade 3A
*HIV+ patient
§The case without IRF4 break was a cryptic translocation demonstrated by RNAseq
#The case without IRF4 mutation was the case of IRF4 translocation with an unknown partner in chr.21
**These cases have other mutations typical of GCB and ABC diffuse large B-cell lymphomas