Grading Gangliogliomas: a Short Case Series With Clinico-Imagistic and Immunohistopathological Correlations.

Due to the completely different clinical outcome, we strongly believe that a grade II ganglioglioma should be differentiated from a grade III GG, based on the lack of mitoses, necrosis and microvascular proliferation. The differentiation between grade II GG and grade I GG should be made on the cellular pleomorphism of both components (glial and neuronal). Based on our experience, we conclude that immunohistochemistry could aid in this differentiation through markers like: Ki67, neurofilament, CD34 and chromogranin A. We strongly believe that further immunohistochemical research on larger study groups will eventually lead to a consensus regarding definitive criteria for grade II gangliogliomas.