[Clinical and radiological analysis of 55 children of basal ganglia germ cell tumors presenting as predominant atrophy].

Objective

To analyze the clinical, laboratory, and radiological characteristics of intracranial germ cell tumors (iGCT) patients with the basal ganglia atrophy as the predominant imaging manifestation.

Methods

In this case series study, clinical data of 55 children diagnosed with iGCT and predominant basal ganglia atrophy (without cystic change or mass effect) admitted to the Department of Pediatrics, Beijing Tiantan Hospital, Capital Medical University, from January 2018 to December 2025 were analyzed retrospectively. Descriptive analysis was conducted on demographic, clinical, radiological and laboratory data. Chi-square test was applied to compare β-human chorionic gonadotropin (β-HCG) positive rates in serum and cerebrospinal fluid (CSF).

Results

All 55 children were male, including 50 (91%) germinomas and 5 (9%) non-germinomatous germ cell tumors (NGGCT). The age at diagnosis was 11 (8, 12) years, with a disease duration of 7 (3, 10) months. Forty-nine children (89%) presented with progressive limb weakness or motor deficit. The β-HCG from serum was increased in 27 children (49%), meanwhile β-HCG from CSF was elevated in 43 children (78%); β-HCG positive rate from CSF was higher than that of β-HCG from serum (χ²=10.06, P=0.002). Only 2 children were tested elevated AFP from serum. All 55 children were tested normal AFP from CSF. The markers of β-HCG and AFP from serum and CSF were both negative in 12 children (22%). Among them, 7 children were confirmed as germinoma by biopsy and 5 children were clinically diagnosed based on comprehensive evaluation. Among the 43 children (78%) with CSF β-HCG positive, 8 germinoma children were confirmed by stereotactic brain biopsy. Despite pathological confirmation of germinoma, 4 of the 8 children were found to meet the diagnostic standard of NGGCT, Left-sided lesions were observed in 35 children (64%), right-sided in 15 children (27%), and bilateral in 5 children (9%). based on tumor marker levels. Those children were ultimately clinically diagnosed as NGGCT. The whole 55 children manifested atrophy of the basal ganglia, T2-weighted and fluid attenuated inversion recovery hyperintensity, and ipsilateral cerebral peduncle atrophy, without definite mass or cystic components from MRI.

Conclusions

The basal ganglia iGCT presenting as predominant atrophy mainly occurs in school-aged or adolescent males, with progressive limb weakness or motor deficit, unilateral atrophy, especially in the left basal ganglia region, accompanied by atrophy of the ipsilateral cerebral peduncle. The increased level of β-HCG from CSF is a key diagnostic clue.