Abstract
Background Secondary gliosarcomas are rare tumors, especially those arising from a World Health
Organization (WHO) grade II glioma not irradiated. We report a case with subtotal
resection for a WHO grade II oligoastrocytoma, without adjuvant treatment, whose metaplastic
transformation into gliosarcoma suddenly occurred 4 years later with meningeal dissemination.
We show a favorable outcome after therapeutic management of this rare entity.
Patient A 46 year-old woman underwent surgery for a right premotor WHO grade II oligoastrocytoma
discovered incidentally. Because of a subtotal resection with only 1 cc of residue,
no complementary therapy was given, and the patient enjoyed a normal life for 4 years.
In the meantime, the magnetic resonance images performed every 6 months showed a very
low growth rate. Suddenly, the tumor switched toward a gliosarcoma profile with meningeal
dissemination.
Results Reoperation, radiotherapy, and chemotherapy were performed, enabling a control of
the disease with 15 months of follow-up (i.e., with radiologic shrinkage of the multiple
lesions and preservation of quality of life).
Conclusion A delayed sarcomatous transformation can acutely occur with a low proliferation index
in a nonirradiated WHO grade II oligoastrocytoma. Furthermore, an aggressive therapeutic
strategy can allow control of secondary gliosarcomas, even in cases of leptomeningeal
spreading.
Keywords
gliosarcoma - WHO grade II glioma - metaplastic transformation - meningeal dissemination
- surgery
