Arq Neuropsiquiatr 2003;61(1):104-106 MALIGNANT TRANSFORMATION OF PLEOMORPHIC XANTHOASTROCYTOMA

ABSTRACT- We report a case of a pleomorphic xantoastrocytoma which manifested itself as a cystic isodense lesion in the right fronto-temporal lobe in a 26 year-old woman. It appeared as a soft yellow tumor with cystic cavities on surgery. Five months after this surgery, the patient was submitted to a new operation, which revealed a friable tumor, easily differentiated from the normal parenchyma, with cystic components. The histopathological examination demonstrated pleomorphic xanthoastrocytoma with malignant transformation. Histologically, the tumor at first procedure was composed of pleomorphic astrocytes with multinucleated and foamy cells. A rare case of malignant transformation in pleomorphic xanthoastrocytoma is presented, discussed and illustrated in this paper. KEY WORDS: xanthoastrocytoma, astrocytoma, tumor, histopathology. Transformação maligna de xantoastrocitoma pleomórfico: relato de caso RESUMO- Um caso raro de transformação maligna de xantoastrocitoma pleomórfico é apresentado, discutido e ilustrado neste estudo. Descrevemos um caso de xantoastrocitoma pleomórfico diagnosticado como lesão isodensa no lobo fronto-temporal direito, em uma paciente de 26 anos. Na cirurgia, encontrou-se tumor mole, de cor amarelada, com cavidade cística. Cinco meses após o procedimento, a paciente foi submetida a nova intervenção que revelou um tumor friável, facilmente diferenciado do parênquima normal, co