Analysis of clinical efficacy and safety of local radiotherapy in children with stage Ⅳ high-risk neuroblastoma / 中华放射肿瘤学杂志

ABSTRACT

Objective To retrospectively analyze the clinical efficacy,safety and influencing factors of radiotherapy in children with stage Ⅳ high-risk neuroblastoma (HR-NB).Methods A total of 120 children with HR-NB who were diagnosed and treated with local radiotherapy according to the BCH-HR-NB-2007 protocol in the Oncology Department of Beijing Children's Hospital from January 2014 to December 2017 were enrolled.Among them,56 children were male and 64 female with a median age of 43 months (9 -148 months).The treatment protocol consisted of 4 cycles of CAV chemotherapy,3 cycles of CVP chemotherapy,surgical resection after 4 cycles,autologous hematopoietic stem cell transplantation after 7 cycles,local radiotherapy at a dose of 15.0-30.6 Gy for 82 cases of primary tumors and 38 cases of primary and metastatic tumors,followed by 13 cis-retinoic acid as maintenance therapy.The entire treatment protocol endured for approximately 18 months.Results The median follow-up time was 21 months.The 3-year local control rate was 84.4％.Before radiotherapy,the 3-year event-free survival rate was 78.4％ in children without metastases,significantly higher compared with 30.4％ in the residual group (P=0.003).The 3-year event-free survival rate was 66.1％ in patients who underwent radiotherapy within 6 months after surgery,significantly higher than 50.6％ in their counterparts receiving radiotherapy at 6 months or more after surgery (P=0.018).Among the children with residual metastases before radiotherapy,the progression rate in children who did not receive radiotherapy was 66.6％,significantly higher compared with 20.0％ in those receiving radiotherapy (P=0.001).All patients had no radiation-related adverse reactions in the liver,kidney and heart,etc.The incidence rate of grade Ⅲ-Ⅳ myelosupression was 24.5％ at 1 week post-radiotherapy,and 8％ at 2 weeks after radiotherapy.Conclusions Radiotherapy yields definite clinical efficacy in the local control of children with stage Ⅳ HR-NB.Early radiotherapy after surgery and radiotherapy for the metastatic lesions can improve the clinical prognosis.No vital organ injuries are observed during the short-term follow-up.At 2 weeks after radiotherapy,the myelosupression is gradually restored.