Primary germinoma of the posterior fossa with CSF and extracranial metastases

A rare case report and literatures review on primary germinoma in cerebellar hemisphere

OBJECT

Primary intracranial germinoma is a rare intracranial lesion which accounts for approximately 0.5-2% of all intracranial tumors. Generally, primary intracranial germinoma occurs in the midline structures of the central nervous system of a pediatric patient. Only four cases of primary cerebellar germinomas with poor prognosis have been previously reported. The object of this paper is to introduce a case of germinoma originating from cerebellar hemisphere and to discuss its clinical features.

METHODS

This paper reported an 8-year-old boy who was diagnosed to have cerebella inflammatory granuloma during hospitalization and then discharged without any operation. However, the follow-up MRs revealed that the lesion became larger. Therefore, the boy was hospitalized again and underwent a gross total resection of lesion. According to pathological examination, the final diagnosis was confirmed as germinoma.

RESULTS

Chemo- and radiotherapy were followed and so far, the patient showed good recovery without any recurrence and metastasis.

CONCLUSION

Primary cerebellar germinoma has been rarely described in previous literatures. In this paper, a primary cerebellar germinoma was reported and its clinical features and treatments were discussed. The tumor's significant shrinkage by CT- scan was firstly reported and maybe this would provide a valuable hint for the diagnosis and treatment on the intracranial germinomas in children.

Radiographic occult cerebellar germinoma presenting with progressive ataxia and cranial nerve palsy

Background

Although the usefulness of susceptibility-weighted imaging (SWI) for detecting basal ganglia germinoma has been reported, the technique is not widely used. We recently encountered an unusual case of primary cerebellar germinoma, presenting with progressive ataxia and cranial nerve palsy, characterized by gradually enlarging low-intensity lesions visible with both T2*-weighted imaging (T2*WI), which were the key to the diagnosis.

Case presentation

A 30-year-old man was referred to our hospital because of slowly progressive dizziness and mild ataxia. Magnetic resonance imaging (MRI) revealed a small, low-intensity spot in the left cerebellar peduncle on the T2*WI and SWI without enhancement. Cerebral angiography revealed no vascular abnormality. The serum α-fetoprotein value was normal. A steroid-pulse was administered as a therapeutic and diagnostic trial, but the symptoms improved little. The patient was discharged from the hospital but soon developed brainstem dysfunction, characterized by dyspnea or hiccups, and he was readmitted. T2*WI imaging revealed expanded and extended spotty lesions in the cerebellum and brainstem, which had not enhanced with contrast agent previously. Targeted stereotactic biopsy of the newly enhanced cerebellar lesion was performed; histopathological examination of the tissue revealed pure germinoma. Serum and cerebral spinal fluid values of beta-human chorionic gonadotropin were not significantly elevated. Chemotherapy with carboplatin and etoposide was initiated. The enhanced lesion disappeared promptly, but the patient continued to require assisted automatic ventilation because of paralysis of respiratory muscles.

Conclusions

We conclude that enlarging low-intensity lesions on T2*WI and SWI may be a reliable clue to the diagnosis of germinomas, irrespective of their location, even without enhancement. Biopsy of the tumor at an early stage is the only way to make the diagnosis conclusively and enable prompt start of treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-015-0516-9) contains supplementary material, which is available to authorized users.

Primary cerebellar germinomas of the posterior fossa

Primary cerebellar germinomas, in the absence of germ-cell tumours outside the nervous system or elsewhere in the cranial cavity and CSF pathways, are exceptional; only two previous cases have been reported in the literature. Two personal observations are described from our 20-year records of intra-axial posterior fossa tumours. The patients were a 32-year-old man and a 17-year-old woman with a clinical history of posterior fossa tumour, studied by computed tomography. The first patient with slight cerebellar signs had a small right hemispheric cerebellar tumour, and the other had a left cerebellar mass with hydrocephalus and progressive intracranial hypertension. Both were treated by tumour removal and irradiation to the whole posterior fossa. The survival times were 58 and 49 months, respectively. The diagnosis of primary cerebellar germinoma cannot be suspected before pathological confirmation. The clinical, neuroradiological and surgical findings are non-specific and quite similar to those of other malignant cerebellar tumours, such as anaplastic gliomas or metastases. Surgery and radiotherapy ensure adequate tumour control in the early stages; cases of recurrence or disseminated disease may be treated by irradiation and chemotherapy.

Cerebellar primary germ-cell tumor in a young boy

Germ cell tumors originating in the posterior fossa are very rare. Described herein is a case of primary germ cell tumor (yolk sac tumor) found in the cerebellar vermis. A 5-year-old boy who complained of headache was admitted. CT and MRI revealed a tumor with diffuse enhancement by contrast medium in the right cerebellar vermis. Total removal was performed and a diagnosis of medulloblastoma or ependymoma was suspected. However, the tumor proved to be a yolk sac tumor with embryonal carcinomatous components from histological findings. Abnormally high levels of alpha-fetoprotein were found in blood and cerebrospinal fluid. Extensive examination indicated that the intracranial lesion had not metastasized from a primary extracranial tumor.