Abstract
Introduction: Extragonadal germinomas rarely emerge from the brain stem; however, proper diagnosis and treatment can result in favorable prognosis. Unfortunately, the preoperative diagnosis of medulla oblongata germinoma is difficult due to insufficient clinical signs and symptoms that are specific to this diagnosis. Case Representation: We present a 12-year-old male patient with an intra-fourth-ventricular germinoma, derived from the medulla oblongata, with no abnormalities in the supratentorial region. The germinoma was initially assessed by advance MRI sequences, including diffusion-weighted imaging, T1 perfusion, and spectroscopy. Conclusion: In summary, although existing imaging technologies cannot completely distinguish germinomas from other primary brain neoplasms in the fourth ventricle, in patients aged between 12 and 40 years, a small mass on the dorsal side of medulla oblongata that emerges into the fourth ventricle and is characterized by homogeneous contrast enhancement, the absence of calcification and hemorrhage, and the lack of hydrocephalus should be considered for a potential medulla oblongata germinoma diagnosis.