Hemorrhagic Brain Tumor As the Initial Presentation of Metastatic Testicular Yolk Sac Tumor: A Case Report and Review of the Literature.

Yolk sac tumors (YSTs) are highly malignant germ cell neoplasms, most commonly arising in the gonads. Intracranial involvement is exceptionally rare and typically affects the pineal or suprasellar regions. Metastatic YST presenting as a hemorrhagic brain lesion is an exceedingly unusual occurrence that poses significant diagnostic and therapeutic challenges. We report the case of a 26-year-old male who presented with rapidly progressive left-sided weakness and headache. Imaging revealed a right frontoparietal hemorrhagic mass with marked vasogenic edema and midline shift. The patient underwent urgent right frontal craniotomy and near-total tumor excision via a transsulcal approach. Postoperatively, neurological recovery was rapid, with near-complete motor improvement within days. Systemic evaluation revealed multiple pulmonary and para-aortic metastases and an enlarged right testis. Serum α-fetoprotein (AFP) was markedly elevated, and histopathological examination confirmed the diagnosis of YST. The patient received adjuvant chemotherapy, followed by radical orchidectomy and lymph node dissection, achieving normalization of AFP and full functional recovery at one year of follow-up. This case underscores the importance of considering germ cell tumors in the differential diagnosis of hemorrhagic brain lesions, particularly in young males. Early surgical intervention, combined with systemic chemotherapy, can lead to favorable neurological and oncologic outcomes even in such rare and aggressive presentations.