Two cases of acute lymphoblastic leukemia with an e1a3 BCR-ABL1 fusion transcript

The e1a3 BCR-ABL1 fusion transcript in Philadelphia chromosome-positive acute lymphoblastic leukaemia: a case report

ABSTRACTThe Philadelphia (Ph) chromosome results from the formation of breakpoint cluster region (BCR)-Abelson 1 (ABL1) fusion gene (BCR-ABL1). The most common type of adult acute lymphoblastic leukaemia (ALL) is Ph chromosome-positive (Ph+); Ph+ ALL has an incidence of 25%∼30%. Several types of BCR-ABL1 fusion transcripts have been reported, including e1a2, e13a2 and e14a2. In addition, some rare BCR-ABL1 transcripts, such as e1a3, have been reported in chronic myeloid leukaemia. However, until now, the presence of e1a3 BCR-ABL1 fusion transcripts has only been reported in a few cases of ALL. In this study, a rare e1a3 BCR-ABL1 fusion transcript was found in a patient diagnosed with Ph+ ALL. However, the patient also suffered from severe agranulocytosis with pulmonary infection and died after being transferred to the intensive care unit before the significance of the presence of e1a3 BCR-ABL1 fusion transcript could be determined. In conclusion, e1a3 BCR-ABL1 fusion transcripts related to Ph+ ALL cases need to be better identified, and appropriate treatment strategies must be designed for such cases.

Aleukemic Extramedullary Blast Crisis as an Initial Presentation of Chronic Myeloid Leukemia with E1A3 BCR-ABL1 Fusion Transcript

Right neck swelling and pain occurred in a 49-year-old man. A Blood count showed a slight increase in platelet count without leukemoid reaction. After a biopsy of the cervical mass and bone marrow aspiration, a diagnosis of extramedullary blast crisis (EBC) of chronic myeloid leukemia (CML) was made. Fluorescence in situ hybridization (FISH) analysis showed a BCR-ABL1 fusion signal, but results of real-time polymerase chain reaction (RT-PCR) for major and minor BCR-ABL1 transcripts were negative. We identified a rare e1a3 BCR-ABL1 fusion transcript. Administration of dasatinib resulted in disappearance of the extramedullary tumor. This is the first reported case of CML-EBC with e1a3 transcript. An aleukemic extramedullary tumor can be the initial presentation of CML.

Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia with e1a3 BCR-ABL1 transcript in a Nigerian with sickle cell anemia: a case report

Background

The occurrence of acute leukemia in patients with sickle cell anemia is uncommon. The Philadelphia chromosome is the hallmark of chronic myeloid leukemia. However, it may also be associated with acute lymphoblastic leukemia and acute myeloblastic leukemia. The common BCR-ABL1 transcripts seen in acute lymphoblastic leukemia are e1a2, e13a2, and e14a2, while other transcripts such as e1a3, e13a3, and e6a2 occur rarely. This report describes the presentation, management, and outcome of the occurrence of B-cell acute lymphoblastic leukemia with the rare e1a3 BCR-ABL1 transcript in a patient with sickle cell anemia.

Case presentation

A 19-year-old male Nigerian, a known sickle cell anemia patient was admitted on account of severe vaso-occlusive crisis. Examination revealed fever, palor, and jaundice. Full blood count showed anemia and leukocytosis. Peripheral blood and bone marrow smears revealed numerous large and small lymphoblasts in keeping with the L2 subtype of acute lymphoblastic leukemia based on the French–American–British classification. Further evaluation was in keeping with a diagnosis of BCR-ABL1-positive mature B-cell acute lymphoblastic leukemia associated with the rare e1a3 transcript. He was commenced simultaneously on induction chemotherapy and Imatinib while being prepared for allogeneic stem cell transplantation. However, he died  six  months after diagnosis from meningoencephalitis.

Conclusion

The occurrence of acute lymphoblastic leukemia with a rare BCR-ABL1 e1a3 transcript in association with sickle cell anemia is uncommon and associated with poor prognosis.

Acute lymphoblastic leukemia with e1a3 BCR/ABL fusion protein. A report of two cases

B Acute Lymphoblastic leukemia (B-ALL) with Philadelphia chromosome (Ph') is a neoplasm of lymphoblast committed to the B cell lineage. The clinical presentation of B-ALL Ph'+ is similar to B-ALL, but is more common in adults than in children. The e1a3 rare variant is produced by the fusion of BCR exon 1 to ABL exon 3. The presence of this translocation has been associated with good disease outcome for chronic myeloid leukemia in a very small series of only 5 cases; there is no such evidence for B-ALL. We report two new cases of B-ALL Ph+ with the rare e1a3 fusion transcript. The e1a3 and e1a2 (p190) transcripts have been reported to have a similar molecular weight and probably a similar clinical profile, thus in these cases the presence of e1a3 was associated with extramedullary infiltration and disease acceleration.

Optimal Molecular Methods in Detecting p190 (BCR-ABL) Fusion Variants in Hematologic Malignancies: A Case Report and Review of the Literature

Patients with BCR-ABL1 positive hematologic malignancies and Philadelphia-like B-lymphoblastic leukemia (B-ALL) are potential candidates for targeted therapy with tyrosine kinase inhibitors (TKI). Before TKIs, patients with B-ALL had a much worse prognosis and current treatments with targeted TKI therapy have improved outcomes. Thus, the detection of BCR-ABL1 is crucial and a false negative BCR-ABL1 result may adversely affect patient care. We report a case of a 76-year-old male with a new diagnosis of B-ALL who was initially found to be BCR-ABL1 negative by quantitative polymerase chain reaction (PCR). A concurrent qualitative PCR was performed which detected a positive BCR-ABL1 result that was confirmed by a next generation sequencing (NGS) based assay and identified as the rare fusion variant e1a3 of p190^BCR-ABL. Based on this result, the patient was placed on dasatinib as a targeted therapy. In the era of molecular diagnostic medicine and targeted therapy, it is essential to have an understanding of the limitations of molecular assays and to follow a comprehensive diagnostic approach in order to detect common abnormalities and rare variants. Incorporating NGS methods in an algorithmic manner into the standard diagnostic PCR-based approach for BCR-ABL1 will aid in minimizing false negative results.