Abstract
BACKGROUND: Non-germinomatous germ cell tumors (NGGCTs) occur 3.5 times more frequently in Chinese children than in western populations. This study aimed to evaluate treatment outcomes, prognostic factors, and diagnostic challenges in a Chinese cooperative group, with particular focus on the roles of pathology and surgical intervention. METHODS: We retrospectively analyzed 62 consecutively diagnosed pediatric patients with NGGCT (September 2018-June 2023) from Shanghai Children's Medical Center and Huashan Hospital. NGGCT was diagnosed by histopathology with/without elevated tumor markers (n = 46) or by elevated markers alone (n = 16). All patients received standardized treatment according to Children's Oncology Group ACNS0122 protocol. Whole-exome sequencing was performed on 12 paired tumor-blood samples to characterize molecular alterations. RESULTS: The study cohort included 49 males and 13 females (median age, 9.8 year). Primary locations were mainly pineal (58%) and suprasellar (29%). Treatment delays (>6 mo) occurred in 21% of patients, particularly those with non-pineal locations and endocrine symptoms. The 3 years event-free survival and overall survival rates were 81.9 ± 5.4% and 91.3 ± 3.7%, respectively. Univariate analysis identified poor prognostic factors: elevated AFP >200 ng/mL, spinal metastases, and lack of complete/partial response after induction chemotherapy. Surgical resection of small residual tumors (<2 cm) provided no survival benefit. Molecular analysis revealed KRAS and KIT as the most frequent mutations, with chromosome 12p abnormalities in 50% of cases. CONCLUSIONS: Standardized multidisciplinary treatment achieves favorable outcomes comparable to international benchmarks. Aggressive surgery does not improve survival when tumor markers normalize. Diagnostic delays remain common, emphasizing the need for improved awareness and referral systems in China.