TABLE 2.
Uncommon Examples of CLL/SLL Transformation
| Case No. | Age, y/Sex | Panel diagnosis | Interesting features |
|---|---|---|---|
| 62 | 75/M | EBV reactivation in CLL/SLL with morphology of EBV+ DLBCL | EBV reactivation in an immunocompromised patient with CLL/SLL manifesting as EBV+ DLBCL. |
| 185 | 79/F | RT-PBL | Concurrent presentation of CLL/SLL with plasmacytic differentiation and lymph node–based RT-PBL diagnosed on pleural effusion. No bone lesions detected. Shared mutations (TP53 and KMT2D) were detected in bone marrow (lower VAFs) and RT-PBL, but IGH::MYC was only seen in PBL. Partial response to myeloma-type treatment. |
| 174 | 63/M | Plasmablastic myeloma | Previously treated longstanding CLL presenting with new-onset renal failure, IGM κ monoclonal protein, and lymphadenopathy. Bone marrow showed plasmablastic plasma cell myeloma with IGH::MYC. IGH gene rearrangement studies suggested a clonal relationship between CLL and plasmablastic myeloma. |
| 37 | 68/M | Burkitt-like lymphoma with 11q aberration | Unusual transformation consistent with Burkitt-like lymphoma with 11q aberration showing a clonal relationship with original CLL (IGH gene rearrangement studies). NGS of CLL and RT sample showed numerous shared and private mutations. Private mutations acquired in RT included TP53, DDR2, and PIK3R1. |
| 143 | 88/F | CLL/SLL and subsequent B-ALL | Presentation of B-lymphoblastic leukemia/lymphoma with IGH::MYC in a soft tissue mass. CLL/SLL and B-ALL did not share trisomy 12 or MYC::IGH abnormalities but showed similar IGHV usage. |
| 217 | 77/M | CLL/SLL transformation to B-ALL | Clonally related transformation to B-ALL in a patient treated with duvelisib. Clonal relationship confirmed by IGH gene rearrangements studies, IGVH sequencing, and shared somatic mutations. |
| 103 | 51/F | High-grade blastic transformation with plasmacytoid dendritic cell and T-cell immunophenotype | Aggressive leukemic transformation with unusual immunophenotype during ibrutinib maintenance, in a patient who previously experienced typical RT. Neoplastic cells showed plasmacytoid dendritic cell and T-cell markers and shared the same IgH gene rearrangement with the CLL clone. |
B-ALL, B-lymphoblastic leukemia/lymphoma; CLL/SLL, chronic lymphocytic leukemia/small lymphocytic lymphoma; DLBCL, diffuse large B-cell lymphoma; EBV, Epstein-Barr virus; NGS, next-generation sequencing; PBL, plasmablastic lymphoma; RT, Richter transformation; VAF, variant allele frequency.