Multifocal cerebral and orbital neoplastic lesions in a 2-year-old child: a case report and literature review emphasizing diagnostic uncertainty and ethical decision-making

Abstract

Background: Multifocal cerebral and orbital neoplastic lesions in early childhood are exceptionally uncommon. Multiple lesions may occur in the context of cancer predisposition syndromes or prior irradiation; in our patient, no syndromic stigmata or prior cranial irradiation were clinically evident, but a genetic predisposition could not be excluded because molecular testing was not performed.

Case presentation: A previously healthy 2-year-old girl presented with chronic headache and progressive right-sided proptosis. MRI and CT identified six anatomically distinct lesions: an intraocular retinoblastoma with orbital extension (histologically confirmed), a right cerebellar lesion consistent with pilocytic astrocytoma (histologically confirmed), and multiple leptomeningeal/cortical enhancing nodules (CSF cytology-supported dissemination). Three additional lesions-right intraconal optic nerve sheath masses, a sellar/suprasellar cystic-solid lesion, and an olfactory-groove enhancing lesion-were radiologically characterized but not tissue confirmed. The child had no known family history of a cancer syndrome and no prior radiation exposure; however, inherited or mosaic predisposition could not be ruled out in the absence of genetic testing.

Conclusion: This case represents an exceptionally complex pediatric presentation of multifocal cerebral and orbital neoplastic disease with mixed diagnostic certainty, rather than definitive evidence of six histologically distinct synchronous primary tumors. This case underscores that multiple spatially and pathologically discrete brain tumors can arise in a pediatric patient without identifiable risk factors. It highlights the importance of comprehensive evaluation to distinguish synchronous primaries from dissemination or a unified underlying process, and of pursuing germline/mosaic genetic assessment whenever feasible. Further study is needed to understand the etiology of such multiple tumor formations and to guide surveillance and management in similarly complex cases.

Keywords: Brain CT; Brain MRI; Child; Intracranial tumors.