Abstract:Objective To study the occurrence of serious adverse events (SAEs) related to chemotherapy with CCCG-ALL-2015 regimen in children with acute lymphoblastic leukemia (ALL) and the risk factors for death after the SAEs. Methods A retrospective analysis was performed on the medical data of 734 children with ALL. They were treated with CCCG-ALL-2015 regimen from January 2015 to June 2019. The occurrence of SAEs during the treatment was investigated. The children with SAEs were divided into a death group with 25 children and a survival group with 31 children. A multivariate logistic regression analysis was used to analyze the risk factors for death after the SAEs. Results Among the 734 children with ALL, 56 (7.6%) experienced SAEs (66 cases) after chemotherapy, among which 41 cases occurred in the stage of remission induction therapy. Of all 66 cases of SAEs, 46 (70%) were infection-related SAEs, including 25 cases of septic shock (38%), 20 cases of severe pneumonia (30%), and 1 case of severe chickenpox (2%), and 87% of the children with infection-related SAEs had neutrophil deficiency. The most common infection sites were blood and the lungs. The most common pathogens were Gram-negative bacteria, viruses, fungi, and Gram-positive bacteria. There were 16 cases (24%) of hemorrhage-related SAEs, with 11 cases of gastrointestinal bleeding (17%), 4 cases of pulmonary bleeding (6%), and 1 case of intracranial bleeding (2%). Of all 734 children with ALL, 66 (9.0%) died, among whom 25 died due to SAEs. The treatment-related mortality rate was 3.4%, and infection (72%) and bleeding (24%) were the main causes of death. Severe pneumonia was an independent risk factor for treatment-related death in ALL children (OR=4.087, 95% CI: 1.161-14.384, P=0.028). Conclusions SAEs often occur in the stage of remission induction therapy, and infection-related SAEs are more common in ALL children accepting chemotherapy with CCCG-ALL-2015 regimen. The development of severe pneumonia suggests an increased risk for death in these children.