SET-NUP214 Fusion Gene Involved Early T-Cell Precursor Acute Lymphoblastic Leukemia in Adult with B Marker Expression

Therapeutic challenges in peripheral T-cell lymphoma

Peripheral T-cell lymphoma (PTCL) is a rare and heterogeneous group of hematological malignancies. Compared to our knowledge of B-cell tumors, our understanding of T-cell leukemia and lymphoma remains less advanced, and a significant number of patients are diagnosed with advanced stages of the disease. Unfortunately, the development of drug resistance in tumors leads to relapsed or refractory peripheral T-Cell Lymphomas (r/r PTCL), resulting in highly unsatisfactory treatment outcomes for these patients. This review provides an overview of potential mechanisms contributing to PTCL treatment resistance, encompassing aspects such as tumor heterogeneity, tumor microenvironment, and abnormal signaling pathways in PTCL development. The existing drugs aimed at overcoming PTCL resistance and their potential resistance mechanisms are also discussed. Furthermore, a summary of ongoing clinical trials related to PTCL is presented, with the aim of aiding clinicians in making informed treatment decisions.

Comparison of flowcytometry-based scoring system for the diagnosis of early T precursor-acute lymphoblastic leukemia

BACKGROUND

Early T cell precursor-acute lymphoblastic leukemia (ETP-ALL) is a hematolymphoid malignancy where the blasts demonstrate T cell differentiation markers along with stem cell and myeloid antigen expression. The differential diagnosis of ETP-ALL from non-ETP ALL and mixed phenotype acute leukemia is often challenging due to its overlapping immunophenotypic picture with co-expression of myeloid antigens. In this study, we endeavored to describe the immune-phenotype profile of ETP-ALL in our patients and compared the utility of four different scoring systems for better discrimination of these entities.

METHODS

This retrospective analysis included 31 ETP-ALL out of 860 acute leukemia cases consecutively diagnosed at the two tertiary care centers. Flowcytometry-based immunophenotype was reviewed for all the cases, and the utility of four flow-based objective scorings was assessed for the diagnosis of ETP-ALL. Receiver operating curves were drawn to compare the different flow-based scoring systems.

RESULTS

The prevalence of ETP-ALL was 40% (n = 31/77 T-ALL) in our study group, comprised mainly of adults with a median age of 20 years. The five-marker scoring system had the maximum area under the curve, followed by the seven-marker scoring system. A cut-off of ≥2.5 was more specific (sensitivity: 91%; specificity: 100%), while a score of ≥1.5 was more sensitive but slightly less specific (sensitivity: 94%, specificity: 96%).

CONCLUSION

The WHO criteria for the diagnosis of ETP-ALL should be followed across all laboratories to avoid confusion and for better treatment stratification. Flow-based scoring systems can be objectively employed for better detection of cases.

SET-CAN/NUP214 fusion gene in leukemia: general features and clinical advances

SET-CAN/NUP214 fusion is a recurrent event commonly observed in adult male patients diagnosed with T-cell acute lymphoblastic leukemia (T-ALL) and has occasionally been reported in other diseases such as acute myeloid leukemia (AML), myeloid sarcoma (MS), acute undifferentiated leukemia (AUL), chronic myeloid leukemia (CML) and B-cell acute lymphoblastic leukemia (B-ALL). This fusion gene is derived from chromosome del(9)(q34.11;q34.13) or t(9;9)(q34;q34) and may have an inhibitory effect on primitive progenitor differentiation. The prognosis of the reported patients is varied, with these patients often show resistance to chemotherapy regimens that include high doses of glucocorticoids. The optional treatment has not been determined, more cases need to be accumulated and evaluated. The scope of this review is to summarize the general features and prognostic significance in leukemia associated with the SET-CAN/NUP214 fusion gene and to discuss the methods of detection and treatment, aiming at providing some useful references for relevant researchers in the field of blood tumor.

Unusual Presentation of SET::NUP214-Associated Concomitant Hematological Neoplasm in a Child-Diagnostic and Treatment Struggle

Simultaneous multilineage hematologic malignancies are uncommon and associated with poorer prognosis than single-lineage leukemia or lymphoma. Here, we describe a concomitant malignant neoplasm in a 4-year-old boy. The child presented with massive lymphoproliferative syndrome, nasal breathing difficulties, and snoring. Morphological, immunocytochemical, and flow cytometry diagnostics showed coexistence of acute myeloid leukemia (AML) and peripheral T-cell lymphoma (PTCL). Molecular examination revealed a rare t(9;9)(q34;q34)/SET::NUP214 translocation as well as common TCR clonal rearrangements in both the bone marrow and lymph nodes. The disease showed primary refractoriness to both lymphoid and myeloid high-dose chemotherapy as well as combined targeted therapy (trametinib + ruxolitinib). Hence, HSCT was performed, and the patient has since been in complete remission for over a year. This observation highlights the importance of molecular techniques for determining the united nature of complex SET::NUP214-positive malignant neoplasms arising from precursor cells with high lineage plasticity.

[Clinical efficacy and safety of venetoclax combined with multidrug chemotherapy in the treatment of 15 patients with relapsed or refractory early T-cell precursor acute lymphoblastic leukemia]

Objective: To explore the efficacy and safety of Venetoclax combined with multidrug chemotherapy in patients with relapsed or refractory early T-cell precursor acute lymphoblastic leukemia (R/R ETP-ALL) . Methods: This study retrospectively analyzed 15 patients with R/R ETP-ALL who received Venetoclax combined with multidrug chemotherapy from December 2018 to February 2022. Among them, eight cases were combined with demethylated drugs, four cases were combined with demethylated drugs and HAAG chemotherapy regimen, two cases were combined with demethylated drugs and CAG regimen, and one case was combined with Cladribine. Specific usage and dosage of Venetoclax: 100 mg on day 1, 200 mg on day 2, 400 mg on day 3-28, orally; when combined with azole antifungal drugs, dosage was reduced to 100 mg/d. Results: Fifteen patients (10 males and 5 females) with R/R ETP-ALL were treated with Venetoclax and multidrug chemotherapy with a median age of 35 (12-42) years old. Of 4 refractory and 11 relapsed patients, the efficacy was evaluated on the 21th day following combined chemotherapy: the overall response rate, the complete response (CR) rate, and the CR with incomplete hematological recovery (CRi) rate were 67.7% (10/15), 60.0% (9/15), and 6.7% (1/15), respectively. For the overall study population, the 12-month overall survival (OS) rate was 60.0%, and the median OS was 17.7 months. The disease-free survival (DFS) rate of all CR patients at 12 months was 60.0%, and the median DFS did not reach. About 14 patients had Ⅲ-Ⅳ hematological toxicity, but these adverse reactions were all controllable. No adverse reaction in the nervous system and tumor lysis syndrome occurred in this study, and no adverse reaction of organs above grade Ⅲ occurred. Conclusion: Venetoclax combined with multidrug chemotherapy may be a safe and promising treatment option for patients with R/R ETP-ALL.