Primary anaplastic pleomorphic xanthoastrocytoma in adults. Case report and review of literature

BACKGROUND Pleomorphic xanthoastrocytoma (PXA) classified as a low Grade (WHO II) astrocytic neoplasm. It is known for its relatively favorable prognosis. It most commonly occurs in young adults. Malignant progression in PXA has been frequently reported since its first description in 1979; however, the presentation of a primary anaplastic PXA tumor with an aggressive clinical course in adults is rare especially in the later age group. CASE DESCRIPTION We present a case of primary anaplastic PXA in a 53 year old male that manifested with an early recurrence pattern at 9 weeks. Treatment performed was surgical excision and external beam radiotherapy. The aforementioned tumor followed an aggressive clinical course. Tumor cells exhibited the characteristic expression of GFAP (Glial fibrillary acidic protein), higher proliferative index (8-10%) on Ki-67 staining along with the presence of increased mitoses ( >5/10hpf). A review of previously reported primary anaplastic pleomorphic xanthoastrocytoma cases in adults with histological features was also done. CONCLUSION Our review of all reported cases of APXA in adults concludes that the clinical behavior of this tumor varies considerably from its benign variant. Early disease recurrence in anaplastic pleomorphic xanthoastrocytomas is associated with fatal outcomes. As per our review of literature it is seen that anaplastic variant of PXA shows histological characteristics as well as clinical course comparable with Grade III astrocytomas. We recommend further evaluation of PXA with anaplastic features regarding their genetic characteristics to understand the origin as well as behavior of this tumor.