Very late relapse cases of TCF3-ZNF384-positive acute lymphoblastic leukemia

ZNF384 rearrangement in acute lymphocytic leukemia with renal involvement as the first manifestation is associated with a poor prognosis: a case report

Background

Novel fusion genes such as ZNF384, have been identified in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) in recent years. Patients harboring ZNF384 rearrangements have a distinctive immunophenotype with weak CD10 and aberrant CD13 and/or CD33 expression. Thus, ZNF384-rearranged ALL is a unique subtype of BCP-ALL. However, research on the prognostic significance of ZNF384 rearrangements has been limited to date, especially in adolescents.

Case presentation

We described a 17-year-old adolescent who was diagnosed with ALL and had renal involvement as the first manifestation, which was very rare in the existing studies. FISH analysis indicated a rearrangement of ZNF384 according to its probe. The patient had a typical characteristic immunophenotype of ZNF384 rearrangement, with CD10 negativity and CD13 and CD33 positivity. She had an unfavorable prognosis because she responded poorly to chemotherapy and developed a relapse shortly after reaching CR.

Conclusion

The importance of ZNF384 rearrangements in terms of prognosis remains unclear. We reported an adolescent who was diagnosed with ZNF384-rearranged ALL with renal involvement. She underwent different therapies, but her prognosis remained poor. Since ZNF384 rearrangements may act as a prognostic predictor in children or adolescents, early detection based on its characteristic immunophenotype is of great necessity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13039-022-00583-4.

Genetic Alterations in Childhood Acute Lymphoblastic Leukemia: Interactions with Clinical Features and Treatment Response

Acute lymphoblastic leukemia (ALL) is the most common cancer among children. This aggressive cancer comprises multiple molecular subtypes, each harboring a distinct constellation of somatic, and to a lesser extent, inherited genetic alterations. With recent advances in genomic analyses such as next-generation sequencing techniques, we can now clearly identify >20 different genetic subtypes in ALL. Clinically, identifying these genetic subtypes will better refine risk stratification and determine the optimal intensity of therapy for each patient. Underpinning each genetic subtype are unique clinical and therapeutic characteristics, such as age and presenting white blood cell (WBC) count. More importantly, within each genetic subtype, there is much less variability in treatment response and survival outcomes compared with current risk factors such as National Cancer Institute (NCI) criteria. We review how this new taxonomy of genetic subtypes in childhood ALL interacts with clinical risk factors used widely, i.e., age, presenting WBC, IKZF1del, treatment response, and outcomes.

Leukemia With TCF3-ZNF384 Rearrangement as a Distinct Subtype of Disease With Distinct Treatments: Perspectives From A Case Report and Literature Review

Background

ZNF384 rearrangements are found in 5-10% of B-cell acute lymphoblastic leukemia (B-ALL) and 48% of B cell/myeloid mixed phenotype acute leukemia (B/M MPAL). ZNF384-rearranged B-ALL is prone to lineage conversion after chemotherapy. TCF3 is the second most common rearrangement partner of ZNF384 in B-ALL (27.5%) and the most common partner in B/M MPAL (53.3%). TCF3-ZNF384 fusion is related to a poor steroid response and a high frequency of relapse. It is mostly reported in children and adolescents but rarely seen in adults.

Patients and Methods

Here, we report a rare case of adult common B-ALL with TCF3-ZNF384 fusion in which the patient relapsed after one cycle of consolidation chemotherapy. Relapsed leukemia cells from the bone marrow were cultured for 72 hours ex vivo, and a panel of 156 kinds of cytotoxic drugs, targeted therapy drugs, combination chemotherapy drugs, etc., was used for sensitivity screening. The literature on TCF3-ZNF384 fusion was reviewed, and reported cases with TCF3-ZNF384 fusion were summarized. Clinical characteristics were compared between B-ALL and MPAL with TCF3-ZNF384 fusion.

Results

The relapsed lymphoblasts showed moderate sensitivity to both acute myelocytic leukemia (AML) - and acute lymphoblastic leukemia (ALL)-directed combination chemotherapy schemes, as well as to multiple targeted therapeutic drugs. The hyper-CVAD (B) scheme showed synergistic effects with multiple targeted compounds and had the highest sensitivity. The patient chose the hyper-CVAD (B) scheme combined with sorafenib and achieved complete remission (CR), then consolidated with myeloid-directed homoharringtonine+cytarabine+daunorubicin (HAD) scheme and gained molecular CR. By reviewing the literature, we found that both the genomic landscapes and gene expression profiles of ZNF384-rearranged B-ALL and MPAL are similar and that both diseases have lineage plasticity. The gene expression profile in TCF3-ZNF384-positive patients shows enrichment of hematopoietic stem cell features. No significant differences in clinical characteristics were found between TCF3-ZNF384-positive ALL and MPAL.

Conclusion

TCF3-ZNF384-positive leukemia may be a distinct subtype of leukemia regardless of immunophenotype. Considering the frequent lineage switches and sensitivity to both ALL- and AML-directed schemes, a uniform strategy directed at both lymphoid and myeloid lineages or at hematopoietic stem cells may be better for TCF3-ZNF384-positive leukemia. Small molecule targeted therapies may be promising treatment options and deserve further investigation.

The Prognostic Significance of ZNF384 Fusions in Adult Ph-Negative B-Cell Precursor Acute Lymphoblastic Leukemia: A Comprehensive Cohort Study From a Single Chinese Center

Novel recurrent fusion gene types such as zinc finger protein 384 (ZNF384) fusions have been identified in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) with the application of next-generation sequencing technologies. However, the comprehensive large-scale clinical cohort study for clarifying their prognostic significance remains scarce to date. A total of 242 consecutive adult Ph-negative BCP-ALL patients treated in our institute were retrospectively screened ZNF384 fusions at diagnosis by multiplex real time quantitative PCR. ZNF384 fusions were identified in 47 patients (19.4%) and all belonged to B-other ALL (having no high hyperdiploid karyotype, BCR-ABL1, TCF3-PBX1, ETV6-RUNX1, or MLL rearrangement). In the whole cohort, patients with ZNF384 fusions had significantly higher 3-year relapse-free-survival (RFS) and tended to have a higher 3-year overall survival (OS) than those with no ZNF384 fusions (80.1% vs. 52.5%, P = 0.013; 67.6% vs. 54.0%, P = 0.10). For patients receiving chemotherapy alone and received allogeneic-hematologic stem cell transplantation (allo-HSCT) were censored at the time of transplantation, patients with ZNF384 fusions had both similar RFS and similar OS to B-other ALL patients with no ZNF384 fusions (RFS: P =0.94 and 0.30; OS: P =0.94 and 0.51). For patients receiving transplantation, those with ZNF384 fusions had significantly higher 3-year RFS than B-other ALL patients with no ZNF384 fusions and their OS were similar (P = 0.022 and 0.24). Only two of 31 patients with ZNF384 fusions and receiving allo-HSCT relapsed, individually occurred 66.8 and 69.8 months after transplantation. Therefore, ZNF384 fusion is common in adult BCP-ALL, which may define a new group from BCP-ALL containing no classical fusion transcript with better prognosis through receiving allo-HSCT.