HGG-04. INFANTILE HIGH GRADE GLIOMA: HONG KONG EXPERIENCE

OBJECTIVE: To review local infantile high-grade glioma (IHG) patients and their outcome. BACKGROUND: Infantile high-grade glioma is diagnosed in patients less than 12 months of age. Studies have shown that it displays a more stable genome, and are usually single mutation driven. The most identifiable mutations are receptor tyrosine kinase (RTK) fusion, such as NTRK family, ROS1, ALK and MET. The current principal treatment remains to be surgery, but it is challenging for a complete resection due to hemispheric involvement. Chemotherapeutic drugs for IHG are still under debate, with targeted therapy showing efficacy in promoting tumour shrinkage. Despite being a challenging CNS tumour, the overall survival of IHG is superior to other paediatric high-grade gliomas. Result: We identified 7 IHG patients in our local data. Mean age of diagnosis was 3 months. There were 4 males and 3 females. Six patients had histological diagnosis of glioblastoma and 1 patient had diagnosis of anaplastic astrocytoma. One patient had her tumour located in infratentorial region. Three patients had multilobar involvement. NTRK fusion was found in 4 patients (NTRK fusion, ETV6-NTRK3 fusion and TPR-NTRK1 fusion). ALK fusion was found in 1 patient (HMBOX1-ALK). All patients underwent chemotherapy, with four patients switched to NTRK inhibitor afterwards. Surgery was performed at various time points for these patients. One patient passed away at 22 months of age at submission of this abstract. CONCLUSION: A local review gives us more insight into the updated diagnosis, management and outcome of infantile patients diagnosed with high-grade glioma. Infantile high-grade glioma should be regarded as a unique tumour entity and a multidisciplinary approach is paramount in improving survival for this group of patients.