Postoperative Skip Metastasis of Pediatric Atypical Choroid Plexus Papilloma: Clinical Considerations on the Role of Copy-Number Variations and Literature Review

Background: Despite advances in methylation-based subclassification, pediatric atypical choroid plexus papillomas (aCPPs) may show an unpredictable, aggressive clinical course. Observation: We report a 7-year-old boy with infratentorial aCPP who developed skip metastasis to supratentorial and spinal regions without local recurrence, 2 years after gross total resection (GTR). Methylation profiling classified the tumor as adult-type, while copy-number analysis revealed 15q amplification and 21q/22q deletions. Conclusion: We report the first pediatric aCPP with delayed distant supratentorial metastasis after GTR without recurrence at the primary surgical site. The current evidence remains insufficient to clarify the metastatic clinical course associated with an adult-type methylation profile.