Clinical and Genomic Phenotype of Brain Metastasis in Nasopharyngeal Carcinoma

Brain metastasis in nasopharyngeal carcinoma is a rare but poor prognosis clinical problem. This study aims to investigate the clinical characteristics and identify the genomic profiling of nasopharyngeal carcinoma brain metastasis. Patients with a diagnosis of nasopharyngeal carcinoma who visited at the Fifth Affiliated Hospital of Sun Yat-sen University since January 2013 to December 2023 were retrospectively collected. Clinical data of patients diagnosed with nasopharyngeal carcinoma brain metastasis were extracted. Paraffin blocks of NPC brain metastases were acquired for immunohistochemistry and genetic testing. High-throughput second generation sequencing was performed for genomic analysis. The mutation landscape was further analyzed. Of the 2378 NPC patients from our database, only six were clinically diagnosed with nasopharyngeal carcinoma brain metastasis. Three were pathologically diagnosed with nasopharyngeal carcinoma brain metastasis. The time interval from the first diagnosis of nasopharyngeal carcinoma to brain metastasis was 15-56 months. The common sites of brain metastasis were frontal lobe and cerebellum, and could be single or multiple, cystic or solid lesions. The OS ranged from 7 to 48 months. Single nucleotide variants were found in 32 genes, such as PTEN, TP53, NFKBIA, KMT2C, and NOTCH1. Copy number variation occurred in five genes, including PTEN, CCDN1, FGF19, FGF3 and FGF4. PTEN and fibroblast growth factors might be involved in the molecular regulation of brain metastasis in nasopharyngeal carcinoma.