Malignant progression in pleomorphic xanthoastrocytoma: Personal experience and review of the literature Elisabetta Marton a, ⁎ , Alberto Feletti a , Enrico Orvieto b , Pierluigi Longatti a a Neurosurgery Department, Regional Hospital of Treviso-Padova University, Piazza Ospedale, 1; 31100 Treviso, Italy b Pathology Department, Regional Hospital of Treviso, Piazza Ospedale, 1; 31100 Treviso, Italy Received 29 June 2006; received in revised form 27 August 2006; accepted 8 November 2006 Available online 26 December 2006 Abstract Pleomorphic xanthoastrocytoma (PXA) is a rare primary low-grade astrocytic tumor, recently classified as a neuroglial tumor. It generally occurs in children and young adults and shows benign behaviour (WHO II), although an anaplastic variant and malignant potential have been described. Pleomorphic xanthoastrocytomas with malignant transformation have been reported in three out of eight patients operated on for this type of tumor in our department in the last 15 years. The three patients were two adult women and a child, the primary tumors were located in the cortex of the right temporal lobe, and treatment consisted of complete surgical resection. Histological examination revealed simple PXA in two patients and a PXA with anaplastic foci in the other. Mean recurrence time was 5.7 years, with the original xanthoastrocytoma evolving to glioblastoma in two cases and anaplastic astrocytoma in the third. All three patients underwent a second operation, followed by adjuvant therapies. Two died from tumor progression and one from brain edema after intracerebral haemorrhage. A review of the available PXA literature dating back to 1979 revealed 16 cases of primary anaplastic astrocytoma and 21 cases of PXA with malignant transformation. Our experience adds three more cases of malignant transformations, outlining once again the potential malignancy of pleomorphic xanthoastrocytomas and the fact that prognosis in these cases is the same as for primary anaplastic astrocytoma and glioblastoma. Analysis of glioneuronal markers, Ki67 and p53 in all pleomorphic xanthoastrocytomas did not prove to be a discriminating factor to identify a subgroup of xanthoastrocytomas prone to malignancy. Accordingly, these tumors demand close long-term clinical and radiological follow-up. © 2006 Elsevier B.V. All rights reserved. Keywords: Xanthoastrocytoma; Low-grade glioma; Malignant transformation 1. Introduction Pleomorphic xanthoastrocytoma (PXA) is a rare low- grade glial tumor described for the first time in 1979 by Kepes [1]. This tumor is superficially located, involves the cortex and leptomeninges but not the dura, and generally occurs in children and young adults. The temporal lobe is the predominant site of location and seizures are the main manifestation. PXAs are generally supratentorial, but cerebellar lesions have also been described [2,3]. They tend to be cystic with a mural nodule. Histological features include marked cellular pleomorphism, variable lipidization, abundant reticulin and perivascular inflammatory cells, with no necrosis. PXA is classified as a low-grade astrocytic tumor (WHO II), but recent studies have demonstrated the presence of both neuronal and glial markers in the tumor cells, and the presence of neuroglial differentiation suggests that they may derive from multipotential precursor cells [4]. The tumor is generally associated with long survival after complete surgical excision and has a favourable prognosis. However, cases of PXA with primary anaplastic features and malignant potential are less uncommon than previously reported [3,5–33]. Journal of the Neurological Sciences 252 (2007) 144 – 153 www.elsevier.com/locate/jns ⁎ Corresponding author. Tel.: +39 0422 322576; fax: +39 0422 322523. E-mail address: emarton@ulss.tv.it (E. Marton). 0022-510X/$ - see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.jns.2006.11.008