Cerebellopontine angle oligodendroglioma in a child: first case report

Secondary cerebellopontine angle oligodendroglioma after cranial irradiation: a case report and literature review

PURPOSE/AIM

Cerebellopontine angle (CPA) oligodendrogliomas are very rare, and only three preoperative cases have been confirmed. Secondary CPA oligodendrogliomas after radiation therapy are exceptionally rare, and no other cases have been reported.

CASE REPORT

We present a case of a 25-year-old male with CPA oligodendroglioma who experienced hearing loss in right ear with walking instability for more than 2 months. The patient underwent craniotomy in our hospital because of grade II astrocytoma of the right temporal lobe 10 years ago. Postoperative radiotherapy lasted for 30 days, and six rounds of chemotherapy were performed. Magnetic resonance imaging (MRI) of the head revealed a cystic lesion located in the right CPA. The patient underwent surgery without obvious complications, and the tumor was subtotally removed. Histopathological examination revealed a diagnosis of oligodendroglioma, World Health Organization (WHO) grade II. The patient was discharged on the tenth postoperative day with a good recovery. Two weeks after discharge, chemotherapy with temozolomide and radiotherapy were performed. The patient remained well at 8 months follow-up.

CONCLUSIONS

To the best of our knowledge, no other cases of secondary CPA oligodendroglioma after cranial irradiation have been reported in the literature. Compared with general oligodendroglioma, the tumor has no typical calcification and is more aggressive. The cranial nerves in the CPA area are closely adhered, and the blood supply is abnormally rich. It is difficult to completely remove the tumor. Postoperative radiotherapy and chemotherapy should be carried out as soon as possible.

Cerebellar Peduncle Localized Oligodendroglioma: Case Report and Review of the Literature

BACKGROUND

Oligodendrogliomas constitute 5% of all primary brain tumors and are the third most common cancer among intracranial tumors. More than 90% of oligodendrogliomas have supratentorial localization. Oligodendrogliomas arising in cerebellar peduncle are substantially rare, <1%. Up to now, 6 oligodendroglioma cases with cerebellar peduncle localization have been presented. We aimed to discuss our World Health Organization grade II oligodendroglioma case, which originated from cerebellar peduncle in the light of literature.

CASE DESCRIPTION

We report a case of 43-year-old woman. Her complaints were headache, perioral numbness and gait abnormality. Magnetic resonance imaging revealed cyst-like well-demarcated lesion localized in right cerebellar peduncle. Tumor excision was performed by turning around the tumor.

CONCLUSION

It should be kept in mind that oligodendrogliomas may be present as cerebellar peduncle localized tumors.

Conventional and advanced (DTI/SWI) neuroimaging findings in pediatric oligodendroglioma

PURPOSE

Oligodendroglioma are rare pediatric brain tumors. The literature about neuroimaging findings is scant. A correct presurgical diagnosis is important to plan the therapeutic approach. Here, we evaluated the conventional and advanced neuroimaging features in our cohort of pediatric oligodendrogliomas and discuss our findings in the context of the current literature.

METHODS

Clinical histories were reviewed for tumor grading, neurologic manifestation, treatment, and clinical status at the last follow-up. Neuroimaging studies were retrospectively evaluated for tumor morphology and characteristics on conventional and advanced magnetic resonance imaging (MRI).

RESULTS

Five children with oligodendroglioma were included in this study. Four children were diagnosed with a low-grade oligodendroglioma. The location of the tumors included the frontal and temporal lobe in two cases each and the fronto-parietal lobe in one. In all oligodendrogliomas, tumor margins appeared sharp. In the high-grade oligodendroglioma, a cystic and partially hemorrhagic component was seen. In all children, the tumor showed a T1-hypointense and T2-hyperintense signal. The signal intensity on fluid attenuation inversion recovery (FLAIR) images was hyperintense in four and mixed hypo-hyperintense in one child. The anaplastic oligodendroglioma showed postcontrast enhancement and decreased diffusion while the low-grade oligodendrogliomas showed increased diffusion. One low-grade oligodendroglioma showed calcifications on susceptibility weighted imaging.

CONCLUSION

Conventional MRI findings of pediatric oligodendrogliomas are nonspecific. Advanced MRI sequences may differentiate (1) low-grade and high-grade pediatric oligodendrogliomas and (2) pediatric oligodendrogliomas and other brain tumors.