Effect of tandem autologous stem cell transplantation on survival in pediatric patients with high-risk solid tumors in South China.

Background: Despite advances in treatment, the prognosis for patients with high-risk pediatric solid tumors remains dismal. Tandem autologous stem cell transplantation (ASCT) offers promise for improving outcomes in these patients. This study aimed to examine the efficacy and prognostic factors of tandem ASCT in pediatric patients with high-risk solid tumors.

Aim: To determine the survival outcomes and prognostic factors in pediatric patients with high-risk solid tumors undergoing tandem ASCT.

Methods: A total of 40 pediatric patients with high-risk solid tumors treated from March 2015 to August 2022 were included in this retrospective study. The diagnoses of the patients included neuroblastoma, germ cell tumors, atypical teratoid/rhabdoid tumor, medulloblastoma, and pineoblastoma. After induction chemotherapy, all patients received tandem ASCT and were allocated into two groups (group A and group B) based on high-dose chemotherapy regimens. Prognostic relevance was evaluated by examining patient characteristics, such as sex, age, lactate dehydrogenase levels, primary site, the number of metastatic sites, and bone marrow involvement.

Results: The median follow-up duration since the first ASCT was 24 months (range: 1-91 months), with 5-year overall survival (OS) and event-free survival (EFS) rates of 73% and 70%, respectively, for the entire cohort. The 3-year OS rates were 67% for group A and 87% for group B (P = 0.29), with corresponding 3-year EFS rates of 67% and 79% (P = 0.57). Among neuroblastoma patients, the 5-year OS and EFS were 69% and 63% (P = 0.23). Univariable analysis revealed a notable association of age ≥ 36 months and elevated lactate dehydrogenase level at diagnosis with poorer OS. Despite acute adverse effects, all patients demonstrated good tolerance to the treatment, with no occurrences of transplant-related mortality.

Conclusion: Tandem ASCT demonstrates promising survival outcomes for patients with high-risk solid tumors, particularly neuroblastoma, with manageable toxicity and no transplant-related mortality.