Intracranial germ cell tumors in pediatric and adolescent patients in China: systematic review and meta-analysis

Background: Intracranial germ cell tumors (IGCTs) are rare neoplasms occurring predominantly in pediatric and adolescent patients. They are rare in Western countries, but are more common in East Asia. We conducted this review and meta-analysis of existing evidence to evaluate the treatment condition and prognosis of IGCT in China and explore the associated problems and challenges. Methods: The analysis was carried out with a search of the PubMed, Embase, Wanfang Data, and CNKI databases for literature published until October 2020. Only clinical studies and case reports in China with a pathological diagnosis containing a treatment protocol and long-term survival data of at least 18 months were included in the review. All patients were children or adolescents younger than 24 years old. This meta-analysis examined overall survival (OS) and progression free survival (PFS) at 3 years. The outcomes were pooled using a random effects model. We used the standardized critical appraisal instrument from the Joanna Briggs Institute (JBI) to assess the risk of bias. Results: The final search included 9 studies with 218 patients. The pooled 3-year PFS of patients with germinomas was 98% and of non-germinomatous germ cell tumors (NGGCTs) was 68% in the included studies. For germinomas, the pooled 3-year PFS and OS revealed that combined chemotherapy has a higher efficacy than therapy with radiation alone (100% vs. 90%, P=0.0415; 100% vs. 92%, P=0.0396). Discussion: Patients with germinomas can receive satisfying outcomes, and combined chemotherapy can provide better survival than radiation therapy alone. Further effort is needed in the future to improve survival in the children with IGCTs, with multidisciplinary input being the key to achieving satisfactory outcomes.