Unusual Presentation of a Common Disease: Metastatic Germ Cell Tumor in the Brain.

Brain metastasis (BM) as the first indication of a germ cell tumor (GCT) is quite rare. Typically, BMs are more frequently observed in patients who have relapsed GCTs, particularly those with non-seminomatous histology and extra-cerebral spread. When BMs are present at the initial diagnosis, they pose distinct diagnostic and treatment challenges. The detection of BMs at the time of diagnosis can suggest advanced disease. It may complicate the diagnostic process, particularly when there are no clear indications of a GCT. We reported a case of a 21-year-old male patient who experienced generalized seizures due to a mass lesion in the brain, which is uncommon. He presented to the hospital with a three-week history of right arm soft tissue swelling and a single episode of generalized seizures. A subtotal excision of the brain tumor was performed, and the patient was placed on ventilatory support. He was ultimately diagnosed with a mixed GCT. After receiving palliative whole-brain radiation therapy and four cycles of chemotherapy, the patient was kept on close follow-up but unfortunately succumbed later due to infectious complications. This case highlights the rare occurrence of BM at initial presentation in GCTs, underscoring the aggressiveness of these tumors. It also emphasizes the importance of maintaining a high index of suspicion, obtaining timely pathological diagnosis, and implementing appropriate management.