Clinical Features and Treatment Strategies of Precursor B-cell Lymphoblastic Leukemia with C-myC Rearrangement in Childhood

Abstract Background: Rare cases of Burkitt leukemia/lymphoma (BL) exhibiting a precursor B-cell phenotype (termed herein pre-BLL) were admitted by WHO Classification of Hematopoetic and Lymphoid Tissue, recent evidence suggests that these neoplasms genetically and epigenetically resemble precursor B-cell leukemia/lymphoma (pB-acute lymphoblastic leukemia/lymphoblastic lymphoma (ALL)/LBL) rather than BL. The clinical features and treatment of childhood pre-BLL with C-myC rearrangement are poorly understood.Methods: The clinical features, treatment strategies and follow-up information of 9 cases with pre-BLL diagnosed by Shanghai Children's Medical Center affiliated to Shanghai Jiao Tong University School of Medicine from 2011 to 2020 were retrospectively analyzed.Results: All the 9 cases were confirmed to be pre-BLL by flow cytometry and fluorescence in situ hybridization, morphological classification were L2/L3, immunophenotype was CD10, CD19 positive, CD20, TDT, CD34 selective expression, surface immunoglobulin (sIgM) negative, Kappa and Lambda light chain negative. Most of the pre-BLL cases were accompanied by elevated lactate dehydrogenase (LDH), uric acid levels. 5 cases received intensive chemotherapy with overlapping regimen, and all achieved sustained remission except for 1 case relapse and death. Among the 4 cases who received low-intensity chemotherapy for acute lymphoblastic leukemia, 2 cases died due to early relapse of the disease.Conclusions: Pre-BLL cases are rare. and intensive chemotherapy treatment according to protocols for mature B-cell NHL. Currently, the treatment strategies are still controversial. Considering the small number of cases, multi-center clinical studies should be actively carried out to find a standard treatment plan.