A 59-Year-Old Man with Two Cerebellar Lesions and Disturbed Cerebellar Morphology

Mature teratoma of the cisterna magna in an adult patient

Background:

Teratomas are a rare subgroup of CNS germ cell tumors and are histologically classified into mature teratomas, immature teratomas, and teratomas with malignant transformation. CNS teratomas are infrequently found in the posterior fossa and pure mature teratomas of posterior fossa are rare especially in adults. We present a case of a young adult female with a mature teratoma in the cisterna magna.

Case Description:

A 26-year-old female presented to the neurosurgery clinic with headache, nausea and vomiting for the past 1 year. She was found to have dysdiadochokinesia on neurological examination. Brain magnetic resonance imaging scan showed a-well defined lesion, hyperintense on T1 and hypointense on T2-weighted sequences located within the cisterna magna. She underwent a suboccipital craniotomy with resection of lesion. Histopathology confirmed the diagnosis of mature cystic teratoma.

Conclusion:

Mature teratomas located in the posterior fossa among adults are rare in the literature. We report the second case of mature teratoma in the cisterna magna of an adult patient.

Lateral ventricle pleomorphic xanthoastrocytoma concurrent with Dandy-Walker complex: A case report

INTRODUCTION

Dandy-Walker complex and pleomorphic xanthoastrocytomas are both rare disease entities that typically manifest early in life and are associated with congenital etiological factors. Dandy-Walker complex is a cerebellar malformation associated with a series of anatomical changes. The disease onset is usually at birth or during infancy. Late onset in adulthood is uncommon. Pleomorphic xanthoastrocytoma is a rare WHO grade II astrocytic tumor affecting mainly young adults. Concomitant occurrence of Dandy-Walker complex and pleomorphic xanthoastrocytoma has not been previously reported.

PATIENT CONCERNS AND DIAGNOSIS

A 30-year-old woman with a previous history of unconfirmed resected lateral ventricle meningioma presented with severe headache for 1 day. Imaging examination revealed a mass in the right lateral ventricle with heterogeneous signal patterns, changes in the posterior fossa corresponding to a Dandy-Walker variant, and mild hydrocephalus.

INTERVENTIONS AND OUTCOMES

Surgical complete resection of the mass was achieved. postoperative histopathological examination confirmed WHO grade II pleomorphic xanthoastrocytoma. Three years postsurgery, ventriculoperitoneal shunt was performed due to worsening of hydrocephalus. The patient has since remained symptom-free.

CONCLUSION

This is the first report of concomitant occurrence of Dandy-Walker complex and pleomorphic xanthoastrocytoma. The association of neurological congenital malformation with intracranial neoplasms may be multifactorial, with underlying role of genetic mutations or chromosome alterations.

Posterior Fossa Teratomas in Adults : A Systematic Review

Objective

The occurrence of posterior fossa teratomas in adulthood is extremely rare. In this study, we aimed to report our experience with two cases of posterior fossa mature teratoma in adults who underwent surgical resection. We also performed a systematic review of published papers available to date.

Methods

We retrospectively reviewed the electronic medical records of patients who had onset of posterior fossa teratomas in adulthood at our institute between 1995 and 2020. We evaluated the clinical, radiographic, and pathological features of mature teratomas at the posterior fossa in adulthood. Furthermore, we searched the PubMed, EMBASE, and Web of Science database and reviewed published articles.

Results

We found 507 articles on database review; of them, 102 were duplicates and 389 were excluded based on the inclusion criteria. Finally, 16 cases of posterior fossa from the web search and related articles. Subsequently, we added two cases that underwent surgery at our institute. We analyzed a total of 18 cases of mature teratomas. Headache was the most common (55.6%) symptom. The teratomas showed heterogeneous signals on magnetic resonance imaging. Thirteen patients (72.2%) had lesion at midline, five patients (27.8%) had calcification. Surgical resection was performed in all patients. No studies reported recurrence after resection.

Conclusion

The occurrence of posterior fossa teratomas in adulthood is difficult to diagnose at the initial stage. Radiographic diagnosis alone can lead to misdiagnosis. Pathological confirmation is essential. Surgical resection is a curative option for posterior fossa teratomas in adulthood.