Clinical Neurology and Neurosurgery 114 (2012) 1338–1342 Contents lists available at SciVerse ScienceDirect Clinical Neurology and Neurosurgery j o ur nal homep age: www.elsevier.com/locate/clineuro Case report Malignant transformation of supratentorial ganglioglioma Cheng-Chia Lee a,c , Wei-Hsin Wang a,c , Chun-Fu Lin a,c , Hsin-Hung Chen a,c , Shao-Ching Chen a,c , Shih-Chieh Lin b,c , Sheng-Che Hung b,c , Wan-Yuo Guo b,c , Donald Ming-Tak Ho b,c , Yang-Hsin Shih a,c , Sanford P.C. Hsu a,c,* a Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taiwan b Department of Pathology, Taipei Veterans General Hospital, Taiwan c School of Medicine, National Yang-Ming University, Taipei, Taiwan a r t i c l e i n f o Article history: Received 29 January 2012 Received in revised form 4 March 2012 Accepted 11 March 2012 Available online 3 April 2012 Keywords: Anaplastic Ganglioglioma Malignant transformation 1. Introduction Gangliogliomas in the central nervous system are usually benign; however, incidences of anaplastic change have been reported. Most malignant transformation is related to radia- tion therapy, often occurring several years after treatment [1–3]. This study describes the malignant transformation into anaplastic tumors of two well-differentiated gangliogliomas with unique cell type. These transformations occurred over a period of only eight months and were not related to radiation. This report examines the clinical characteristics, MR images, and histopathological features of these transformed tumors. 2. Case report 2.1. Case 1 A 56-year-old male experienced a sudden onset of heavi- ness accompanied by headache over the period of one month. Brain MR images showed an ill-defined, intra-axial mass in the right parahippocampus with surrounding edema and mass effect. The mass appeared hyperintense on T1-weighted image and * Corresponding author at: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, 17F, No. 201, Shih-Pai Road, Sec. 2, Peitou, Taipei 11217, Taiwan. Tel.: +886 2 28757491; fax: +886 2 28757588. E-mail address: doc3379b@gmail.com (S.P.C. Hsu). hyperintense on T2-weighted image with prior hemorrhage (Fig. 1A). An initial operation was performed on Aug 2010, and the post-op MR image verified the total removal of the tumor. The gross features of the tumor appeared dark-brown, friable, and easily aspiratable. Microscopically, the tumor tissue comprised epithe- lioid astrocytic cells and ganglion cells (Fig. 2, left). The dysplastic ganglion cells were characterized by cytomegaly with prominent nucleolus, and were immunoreactive for SY38, S100 and neu- rofilaments. Staining for GFAP outlined the astrocytic cells with immunoreactivities for MGMT(98%, 2+) and P53(95%, 2+). The MIB- 1 labeling index was 8. Many CD68-immunoreactive microglia or histiocytes were observed. A few melanin pigments were high- lighted using Masson Fontana stain. Because we were under the impression that this was of a benign ganglioglioma, radiotherapy was not administrated. However, eight months following the ini- tial operation, the patient developed further headaches, memory impairment, and personality changes. Subsequent brain MR images showed a recurrent heterogeneously enhanced mass, approxi- mately four cm in size, involving the right anterior mesial temporal lobe, including the right parahippocampal gyrus and hippocam- pus, with a cystic component at the base of the tumor (Fig. 1B). The patient underwent a second operation for the removal of the tumor and the specimens sent for microscopic examination revealed cere- bral tissue with a tumor composed of intermingled GFAP-positive astrocytic cells and synaptophysin-positive ganglion cells (Fig. 2, right). Cystic changes in the tumor were noted. The astrocytic cells showed hypercellularity, nuclear pleomorphism, increased mitotic activity, and focal necrosis. In the most active area, the MIB-1 0303-8467/$ – see front matter © 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.clineuro.2012.03.018