Atypical presentation of a central nervous system germinoma in a pediatric patient. Case presentation

Abstract

Introduction: Germinomas, although infrequent, are the most common germ cell tumors in the pediatric central nervous system (CNS). Unlike other germ cell tumors, they do not alter hormone levels in blood or cerebrospinal fluid. They are typically located in the pineal gland and the selarsuprasellar region, and are seen as expanding masses. They rarely affect vision, unless accompanied by intracranial hypertension. Objective: This study aims to describe an atypical presentation of a CNS germinoma manifesting as decreased visual acuity, associated only with thickening of the floor and anterior wall of the third ventricle, with invasion of the optic chiasm and optic nerves, a presentation not previously described in the literature. Case description: An 11-year-old female patient with short stature presented with decreased visual acuity and dyschromatopsia. Magnetic resonance imaging (MRI) revealed thickening and contrast enhancement of the optic chiasm and optic nerves, as well as the floor and anterior wall (lamina terminalis) of the third ventricle. The neurohypophysis was not visualized. An endoscopic biopsy of the floor of the third ventricle confirmed germinoma. The patient started oncologic treatment with carboplatin and etoposide according to the COG protocol. Conclusion: This case highlights the importance of considering germinoma in pediatric patients with atypical visual and neurologic symptoms. A comprehensive evaluation, including endoscopic biopsy in atypical cases, is crucial for accurate diagnosis and appropriate treatment. It is recommended to maintain a broad differential diagnosis, especially in cases with overlapping symptoms with other pathologies. This study contributes to the understanding of the clinical variability of CNS germinomas in pediatrics, emphasizing the need for further surveillance and study of these rare cases.