Transient spontaneous remission of childhood acute leukemia: report of 3 cases and review of literature / 白血病·淋巴瘤

ABSTRACT

Objective:To investigate the clinical characteristics and possible causes of transient spontaneous remission of childhood acute leukemia.Methods:The data of 3 children with acute leukemia who had transient spontaneous remission before standardized chemotherapy in Sun Yat-sen Memorial Hospital of Sun Yat-sen University in July 2018, May 2019 and October 2020 were collected. Moreover, the related influencing factors of spontaneous remission in leukemia were discussed by review of the literature.Results:All 3 children had fever at the onset of the disease, and they achieved transient spontaneous remission after anti-infection therapy. Case 1 obtained partial remission after the initial diagnosis of acute B lymphocytic leukemia (B-ALL), leukemia gene test showed E2A-PBX1 fusion, and relapsed after 12 days. Case 2 obtained spontaneous remission after the initial diagnosis of B-ALL, leukemia gene test showed p16 gene deletion and NRAS and EP300 genes mutation, and relapsed after 20 days. Case 3 obtained spontaneous remission after the initial diagnosis of acute monocytic leukemia, leukemia gene test showed MLL-ENL fusion and NRAS gene mutation, and relapsed after 30 days. A review of the literature showed that the main influencing factors of spontaneous remission in leukemia were Down syndrome, infection and blood transfusion. Other influencing factors included leukemia-related genes, termination of pregnancy and application of drugs.Conclusions:Transient spontaneous remission of childhood acute leukemia is rare in clinical practice, and the possible mechanism is related to infection-induced immune abnormalities. It is recommended that leukemia patients with spontaneous remission should be closely monitored for minimal residual disease.