Melanotic astrocytoma.

A case of pigmented pilocytic astrocytoma (WHO grade I) incidentally found in a right temporopolar lobectomy specimen is reported. The patient, a 41-year-old woman, underwent surgery because of long-standing complex partial epilepsy of presumed post-traumatic origin. Using immunohistochemistry and electron microscopy, the tumor was shown to be composed of astrocytes without evidence of neurosecretory or melanocytic differentiation. The cytoplasmic pigment was identified as neuromelanin by its histochemical staining properties and ultrastructure. Although rare cases of ependymoma, subependymoma, choroid plexus papilloma and ganglioglioma with melanogenesis are on record, no melanotic astrocytoma has been described so far.