Primary Intracranial Extra-Axial Anaplastic Ependymomas.

BACKGROUND

Ependymomas are usually located in the ventricular system or in the central canal of the spinal cord; intracranial extra-axial ependymomas (IEAEs) are rare. To date, only 17 cases of IEAEs have been reported.

CASE DESCRIPTION

We report 2 cases with 3 IEAEs (anaplastic) that were initially misdiagnosed. In Case 1 (47-year-old male), the para-falcine lesion was initially refractory to radiosurgery and gross total resection (GTR) was required due to relentless growth. The lesion had adhered to the falx and was well demarcated from the surrounding cortex. It was then correctly diagnosed as an anaplastic ependymoma on the basis of histopathology, and the patient received radiotherapy. No recurrence was observed after the 53-month follow-up. In Case 2 (30-year-old male), 2 IEAEs underwent staged surgeries and were identified as extra-axial lesions without connection to the ventricular system. Near total resection (NTR) and GTR were achieved in the right temporal and right occipital lesions, respectively, but the patient declined radiotherapy. The residual tumor after NTR regrew rapidly, and aggressive resection was performed followed by radiotherapy. No further recurrence was observed after 28 months. The previous 17 cases were male predominant (76.5%) without correct preoperative diagnoses; no recurrence was observed after total resection in the 9 patients reported in the literature.

CONCLUSIONS

IEAEs are rare and have a wide spectrum of clinical and radiological phenotypes. Preoperative diagnosis is difficult. Favorable outcomes for IEAEs can be achieved by GTR plus radiotherapy. Multiple IEAEs benefit from tailored staged surgical resection plus radiotherapy.