Suprasellar Germinomas: Case Report and Literature Review

Introduction: Germinomas are a rare and malignant tumor, a type of Germ Cell Tumors (GCTs). They arise from embryonal rests located in the midline due to aberrant migration during early development. Suprasellar germinomas commonly present with diabetes insipidus, visual impairment, and hypothalamic-pituitary failure. More than 90% will respond positively to chemotherapy (ChT) and radiation therapy (RT), making early diagnosis the mainstay.

Case Report: A 11-year-old female patient was referred for progressive visual loss for over than 30 days, leading to bilateral amaurosis, confirmed by neurological examination. MRI evidenced a 2.5 × 2.5 × 2.5 cm expansive sellar/suprasellar mass, slightly hyperintense on T1 and T2, presenting cystic areas, involving the optic chiasm and in close contact with the supraclinoid segment of the internal carotid artery, compressing the pituitary parenchyma; a cystic formation on pineal gland, measuring 0.6 cm; and a enhanced nodular formation on obex, measuring 0.5 cm. Serum prolactin levels were elevated (130 ng/mL). An endonasal endoscopic approach, transsphenoidal surgery was performed, making possible a partial resection. The histopathological was conclusive for Germinoma. The visual deficit improved mildly, the patient progressed with diabetes insipidus, hypernatremia and hypopituitarism. After stabilization, the patient continued on ChT with Etoposide and Ifosfamide. Lately started RT.

Discussion: CNS GCTs occur most commonly in young pacients, with approximately 90% of cases occurring before the age of 20 years and an incidence peak between 10–12 years. Primary Intracranial Germinomas represent approximately 8% of intracranial tumors in pediatric patients. The majority of GCTs most commonly arise in the neurohypophyseal/suprasellar (30%) and pineal regions (50%) or may occur synchronously in both. Racial, genetic, and environmental factors appear to have an influence on the occurrence of these tumors. Surgery is usually recommended for biopsy (because histology is the most important prognostic factor) or to discompress structures. Gross total resection (GTR) may lead to damage in midline structures, so some authors recommend subtotal or near total resection. The treatment is continued with ChT and RT, resulting in a 5-year rate exceeding 80%.

Conclusion: Suprasellar germinomas are highly curable lesions when diagnosed early and should always be considered when lesions in typical locations are found, especially in children.