Diverse B-cell tumors associated with t(14;19)(q32;q13)/IGH::BCL3 identified by G-banding and fluorescence in situ hybridization.

We characterized 5 B-cell tumors carrying t(14;19)(q32;q13) that creates the IGH::BCL3 fusion gene. The patients' ages ranged between 55 and 88 years. Two patients presented with progression or recurrence of B-cell chronic lymphocytic leukemia (B-CLL)/small lymphocytic lymphoma (SLL), two with diffuse large B-cell lymphoma (DLBCL) of non-germinal center B-like phenotype, and the remaining one with composite angioimmunoblastic T-cell lymphoma and Epstein-Barr virus-positive DLBCL. The presence of t(14;19)(q32;q13) was confirmed by fluorescence in situ hybridization (FISH), showing colocalization of 3' IGH and 3' BCL3 probes on der(14)t(14;19) and 5' BCL3 and 5' IGH probes on der(19)t(14;19). One B-CLL case had t(2;14)(p13;q32)/IGH::BCL11A, and 2 DLBCL cases had t(8;14)(q24;q32) or t(8;11;14)(q24;q11;q32), both of which generated IGH::MYC by FISH, and showed nuclear expression of MYC and BCL3 by immunohistochemistry. The IGH::BCL3 fusion gene was amplified by long-distance polymerase chain reaction in 2 B-CLL/SLL cases and the breakpoints occurred immediately 5' of BCL3 exon 1 and within the switch region associated with IGHA1. The 5 cases shared IGHV preferentially used in B-CLL cells, but the genes were unmutated in 2 B-CLL/SLL cases and significantly mutated in the remaining 3. B-cell tumors with t(14;19)(q32;q13) can be divided into B-CLL/SLL and DLBCL groups, and the anatomy of IGH::BCL3 in the latter may be different from that of the former.

[Clinical characteristics of 11 patients with chronic lymphocytic leukemia with t (14;19) (q32;q13)].

Objective: To analyze the clinicopathological characteristics of 11 cases of chronic lymphocytic leukemia (CLL) with t (14;19) (q32;q13) . Methods: The case data of 11 patients with CLL with t (14;19) (q32;q13) in the chromosome karyotype analysis results of the Blood Diseases Hospital, Chinese Academy of Medical Sciences from January 1, 2018, to July 30, 2022, were retrospectively analyzed. Results: In all 11 patients, t (14;19) (q32;q13) involved IGH::BCL3 gene rearrangement, and most of them were accompanied by +12 or complex karyotype. An immunophenotypic score of 4-5 was found in 7 patients and 3 in 4 cases. We demonstrated that CLLs with t (14;19) (q32;q13) had a mutational pattern with recurrent mutations in NOTCH1 (3/7), FBXW7 (3/7), and KMT2D (2/7). The very-high-risk, high-risk, intermediate-risk, and low-risk groups consisted of 1, 1, 6, and 3 cases, respectively. Two patients died, 8 survived, and 2 were lost in follow-up. Four patients had disease progression or relapse during treatment. The median time to the first therapy was 1 month. Conclusion: t (14;19) (q32;q13), involving IGH::BCL3 gene rearrangement, is a rare recurrent cytogenetic abnormality in CLL, which is associated with a poor prognosis.

Clinical characteristics of 11 patients with chronic lymphocytic leukemia with t (14;19) (q32;q13) / 中华血液学杂志

Objective: To analyze the clinicopathological characteristics of 11 cases of chronic lymphocytic leukemia (CLL) with t (14;19) (q32;q13) . Methods: The case data of 11 patients with CLL with t (14;19) (q32;q13) in the chromosome karyotype analysis results of the Blood Diseases Hospital, Chinese Academy of Medical Sciences from January 1, 2018, to July 30, 2022, were retrospectively analyzed. Results: In all 11 patients, t (14;19) (q32;q13) involved IGH::BCL3 gene rearrangement, and most of them were accompanied by +12 or complex karyotype. An immunophenotypic score of 4-5 was found in 7 patients and 3 in 4 cases. We demonstrated that CLLs with t (14;19) (q32;q13) had a mutational pattern with recurrent mutations in NOTCH1 (3/7), FBXW7 (3/7), and KMT2D (2/7). The very-high-risk, high-risk, intermediate-risk, and low-risk groups consisted of 1, 1, 6, and 3 cases, respectively. Two patients died, 8 survived, and 2 were lost in follow-up. Four patients had disease progression or relapse during treatment. The median time to the first therapy was 1 month. Conclusion: t (14;19) (q32;q13), involving IGH::BCL3 gene rearrangement, is a rare recurrent cytogenetic abnormality in CLL, which is associated with a poor prognosis.

[Clinical analysis of 20 cases of small B lymphocyte proliferative disease with t (14;19) (q32;q13)].

Objective: The clinical characteristics and prognosis of 20 patients with small B-lymphocyte proliferative disease with t (14;19) (q32; q13) were analyzed to improve the understanding of such rare cases. Methods: The clinical data of 20 patients with t (14; 19) (q32; q13) small B lymphocyte proliferative disease treated in the First Affiliated Hospital of Nanjing Medical University from April 2013 to December 2020 were retrospectively collected and analyzed. Among them, 10 cases were chronic lymphocytic leukemia (CLL) and 10 cases were other small B-cell malignancies. Results: Among the 20 cases, 10 were male and 10 were female, and the median age at diagnosis was 53.5 (35-88) years old. All patients had absolute lymphocytosis, 19 patients had lymphadenopathy, and 10 patients had splenomegaly. With a median follow-up of 36 (4-163) months, three patients died, and 11 patients had a time to treatment (TTT) ≤12 months. Ten patients (50%) were accompanied by +12, two patients (2/17, 12%) were accompanied by 13q-. Moreover, we found that t (14;19) was associated with unmutated immunoglobulin heavy-chain variable (IGHV) somatic mutation (17/19, 89%) and a biased use of IGHV4-39 (7/17, 41%) was observed. Next-generation sequencing detected one or more gene mutations in 14 (14/17, 82%) cases and a total of 25 gene mutations had been revealed, of which the most frequent were NOTCH1 (35%) , followed by SF3B1 (24%) and KMT2D (18%) . For 10 CLL patients, five (50%) were defined as Rai Ⅲ/Binet C. It is noteworthy that among the 20 cases, two cases actually involved Richter transformation. Conclusions: Small B-cell malignant tumors with abnormal t (14; 19) show unique clinical biological characteristics, often accompanied by a variety of adverse prognostic factors, and tend to have an aggressive clinical course.