Objective:To improve the understanding of acute lymphoblastic leukemia (ALL) secondary to Burkitt lymphoma (BL) in children.Methods:The clinical data of a child with ALL secondary to BL who was admitted to Children's Hospital Affiliated to Zhengzhou University in June 2024 were retrospectively analyzed, and the relevant literature was reviewed.Results:The patient was a boy with the age of 8 years and 8 months. He presented with a neck mass at the age of 4 years and 6 months, and pathological examination revealed a diagnosis of BL with clinical stage Ⅲ. The patient was given regular chemotherapy according to the Chinese Children's Lymphoma Group non-Hodgkin lymphoma mature B-cell 2017 protocol-B2 regimen. PET-CT showed recurrence of lymphoma in 6 months after the suspension of treatment. The patient was given with placement of 125I particles, oral etoposide and dexamethasone, and traditional Chinese medicine. The patient was admitted to hospital at the age of 8 years and 8 months with fever and skin hemorrhagic spots, bone marrow morphology, immunology, cytogenetics and molecular biology typing indicated a diagnosis of B-ALL with TCF3::PBX1 fusion gene. The patient received induction chemotherapy according to the Chinese Children's Leukemia Group-ALL 2018 protocol. A review of bone marrow cytology achieved complete remission on the 33rd day of chemotherapy, and minimal residual disease detected by flow cytometry indicated less than 0.01%. TCF3::PBX1 fusion gene was negative. Conclusions:ALL secondary to BL in children is rare, and the ALL treatment regimens are effective.

Objective:To improve the understanding of pediatric acute promyelocytic leukemia with TTMV::RARA fusion gene positive caused by torque teno mini virus (TTMV).Methods:A retrospective analysis was conducted on the clinical data of a patient with relapsed TTMV::RARA fusion gene-positive acute promyelocytic leukemia who was admitted to Children's Hospital Affiliated to Zhengzhou University in July 2024, and literature review was conducted.Results:The patient was a girl with the age of 5 years and 7 months. She presented with joint pain and fever. Combined with bone marrow cell morphology and whole transcriptome sequencing, she was diagnosed with TTMV::RARA fusion gene-positive acute promyelocytic leukemia. After induction therapy with regimens such as retinoic acid +daunorubicin+cytarabine and retinoic acid+venetoclax+homoharringtonine, the joint pain was relieved, but the primary disease did not improve. Subsequently, there was no regular treatment. One year later, the disease recurred and was complicated with severe infection. Her condition improved following anti-infection and induction therapy.Conclusions:TTMV::RARA fusion gene-positive pediatric acute promyelocytic leukemia is a special type of acute promyelocytic leukemia caused by the insertion of viral sequences from TTMV infection. It is rare in clinical practice and difficult to treat, and the overall prognosis may be poor.