Gliosarcoma arising from an anaplastic ependymoma: a case report of a rare entity

We report the first case of a gliosarcoma arising from an anaplastic ependymoma and the second case of gliosarcoma arising from any type of ependymal neoplasm. The patient was a 48-year-old woman with a solid and cystic, peripherally enhancing, 7-cm right frontal mass lesion. Histologically, the lesion displayed characteristics of anaplastic ependymoma (grade III, World Health Organization scale). The tumor recurred despite multiple cycles of postoperative radiation and chemotherapy. After the fourth recurrence, the tumor displayed a biphasic pattern of differentiation. The first pattern was similar to the original anaplastic ependymoma, whereas there was a second new sarcomatous pattern resembling fibrosarcoma that was admixed with and overrunning the ependymal component. The spectrum of gliosarcoma is therefore expanded to include not only astrocytic and oligodendroglial components but ependymal components as well.

Gliosarcoma occurring 8 years after treatment for a medulloblastoma

CASE REPORT

We present a rare case of a gliosarcoma occurring 8 years following treatment for a medulloblastoma. The patient was diagnosed with a medulloblastoma at the age of 13 years. We considered the possibility of a radiation-induced tumour and present evidence supporting this view. The second cerebral tumour was excised and confirmed to be a gliosarcoma. The tumour bed was re-irradiated with three-dimensional conformal radiotherapy (3DCRT). She remained well for 6 months, after which there was clinicoradiological progression.

CONCLUSIONS

During long-term follow-up of patients with medulloblastomas, the possibility of radiation-induced neoplasms must be borne in mind.

Radiation-associated gliosarcoma

The authors report a case of radiation-associated intracerebral gliosarcoma with fibrosarcomatous predominance, arising at the site of a low-grade glioma treated 10 years previously. The features of this case conform to the accepted criteria for radiation-induced tumour, in that the tumour developed within the radiation field, differed dramatically in histologic features from the original tumour and did not develop until 10 years after treatment. Although such tumours are most uncommon, this case suggests that radiation-induced gliosarcoma should be considered in the differential diagnosis of recurrent mass at the site of a treated intracranial neoplasm.

Radiation-induced gliosarcoma. Case report and review of the literature

A 13-year-old boy presented with a cerebral gliosarcoma 12 years after having acute lymphoblastic leukemia treated by chemotherapy and central nervous system prophylaxis treated by radiation therapy (24 Gy) and intrathecal methotrexate. A review of the literature disclosed 129 possible radiation-induced gliomatous and/or sarcomatous brain tumors: namely, 89 gliomas, 36 sarcomas, and four gliosarcomas, including the present case. An analysis of these cases revealed several characteristics that differentiate them from similar spontaneous brain tumors, thus providing arguments for the carcinogenic effect of radiation therapy on intracranial tumors.