an unusually aggressive clinical behavior in a case of atypical subependymal giant cell astrocytoma

[Downloaded free from http://www.neurologyindia.com on Thursday, November 13, 2014, IP: 202.177.173.189]  ||  Click here to download free Android application fo journal Letters to Editor another six more cases since then.[1‑6] Wein et al have divided the plasmacytoma of the skull base into anterior (nasopharyngeal) group and central (sphenoid, clivus, petrous apex) group This is of prognostic importance because in the central group, the rate of progression to multiple myeloma is 63.6%, which is much higher than that in the anterior group (9.5%) Moreover plasmacytomas are also classified as extramedullary plasmacytoma (EMP) or solitary plasmacytoma of bone (SPB).[1] Most of the anterior group of skull base plasmacytoma fall into EMP group and the central skull base plasmacytoma fall into SPB group Since solitary plasmacytoma represents only one end of the spectrum of plasma cell tumors and represents a distinct manifestation of a disease continuum, progression to multiple myeloma is almost invariable Hence adjuvant therapy is essential to arrest further progression of the disease This patient had involvement of frontal and ethmoidal sinuses and eroding the floor of the anterior cranial fossa and most probably falls into the group of EMP Hence, though the tumor had been excised totally adjuvant radiotherapy was given to the patient The possibility of plasmacytoma has to be kept in mind in any osteolytic tumor of the skull base Acknowledgement We thank Prof K Ramesh Rao, Department of Pathology, Chettinad Superspeciality Hospital, Chennai, for providing the histopathology pictures Ramesh Ganesan Vengalathur, Karthikeyan Veerasamy Kavindapadi, Balasubramanian Chandramouli Department of Neurosurgery, Chettinad Superspeciality Hospital, Chettinad Health City, Kelambakkam, Chennai, Tamil Nadu, India E‑mail: drvgramesh@hotmail.com References 546 Wein RO, Popat SR, Doerr TD, Dutcher PO Plasma cell tumors of the skull base: Four case reports and literature review Skull Base 2002;12:77‑86 Ustuner Z, Basaran M, Kiris T, Bilgic B, Sencer S, Sakar B, et al Skull base plasmacytoma in a patient with light chain myeloma Skull Base 2003;13:167‑71 Singh AD, Chacko AG, Chacko G, Rajshekhar V Plasma cell tumors of the skull Surg Neurol 2005;64:434‑8 Pancholi A, Raniga S, Vohra PA, Vaidya V, Prajapati A, Mansingani S Imaging features of extramedullary plasmacytoma of skull base with multiple myeloma—A rare case Indian J Radiol Imaging 2006;16:29‑32 Yamaguchi S, Terasaka S, Ando S, Shinohara T, Iwasaki Y Neoadjuvant therapy in a patient with clival plasmacytoma associated with multiple myeloma: A case report Surg Neurol 2008;70:403‑7 Guinto‑Balanzar G, Abdo‑Toro M, Aréchiga‑Ramos N, Leal‑Ortega R, Zepeda‑Fernández E, Nambo‑Lucio Mde J Plasma cell tumor of the clivus: Report of two cases Cir Cir 2012;80:171‑6 Access this article online Quick Response Code: Website: www.neurologyindia.com PMID: *** DOI: 10.4103/0028-3886.144457 Received: 16-07-2014 Review completed: 26-08-2014 Accepted: 03-10-2014 An unusually aggressive clinical behavior in a case of atypical subependymal giant cell astrocytoma Sir, Subependymal giant cell astrocytoma (SEGA) is a benign tumor that mostly arises in the wall of the lateral ventricle.[1] Though it has been classified as a low grade, WHO Grade 1 tumor, aggressive lesions with metastasis and intratumoral hemorrhages have been described.[2,3] High grade features like mitoses, focal necrosis, and endothelial proliferations are distinctly rare, but few cases have been reported in the literature with these unusual findings of high‑grade tumor, termed as atypical SEGA.[4,5] Despite anaplasia in histology, the clinical behavior of these patients have been benign, same as typical SEGA A few cases of atypical SEGA may behave aggressively.[5] We report a case of atypical SEGA mimicking malignant glioma with an unusually aggressive clinical course A 5‑year‑old male child presented with 1 month history of worsening headache with right hemiparesis and facial weakness Magnetic resonance imaging (MRI) showed a large lesion in the left posterior thalamic region abutting the atrial wall with peripheral enhancement with edema [Figure 1a and b] There were no markers of tuberous sclerosis complex (TSC) The patient underwent a parietooccipital craniotomy and near total resection of the tumor through transcortical, transventricular route [Figure 1c and d] Immediate postoperative period was uneventful The histology showed spindle‑shaped to large polygonal tumor cells with many multinucleated giant cells scattered in between [Figure 2] Large necrotic areas were observed Few mitotic figures were identified with Ki‑67 labelling index around 2-3% The tumor also showed glial fibrillary acidic protein (GFAP) positivity The overall features were suggestive of SEGA with atypical features Within 3 weeks of primary surgery, the patient presented with altered sensorium and progressively worsening right hemiparesis MRI showed a small Neurology India | Sep-Oct 2014 | Vol 62 | Issue [Downloaded free from http://www.neurologyindia.com on Thursday, November 13, 2014, IP: 202.177.173.189]  ||  Click here to download free Android application for t journal Letters to Editor a b e d c f Figure 1: (a and b) Preoperative MRI showing large heterogeneous left thalamic lesion with peripheral contrast enhancement (c and d) Postoperative CT showing near total excision of the tumor (e and f) Plain CT and contrast-enhanced MRI at months showing large recurrence MRI = Magnetic resonance imaging, CT = computed tomography a b c d Figure 2: (a) Low power photomicrograph showing a cellular tumor with large areas of necrosis (H and E, ×4), (b) The tumor is composed of bizarre, multinucleated cells in a fibrillary background (H and E, ×20) (c) Tumor cells show strong GFAP expression (IP, ×20) (d) Ki-67 immunostain showing high proliferative index in tumor cells (IP, ×40) H and E = Hematoxylin and Eosin, IP = Immunoperoxidase recurrent lesion with hydrocephalus Ventriculoperitoneal shunt was placed following which the sensorium improved In view of the early recurrence and high‑grade histological features, conformal radiotherapy was given A month later, the clinical condition worsened and repeat imaging showed increase in size of lesion with invasion of adjacent structures [Figure 1e and f] Because of the poor general condition, reexcision of tumor could not be offered and the patient subsequently died within a fortnight SEGAs are low‑grade tumors that seem to arise from the ependymal layer lining the ventricular walls They usually arise near the foramen of Monro, though other ventricular Neurology India | Sep-Oct 2014 | Vol 62 | Issue locations have been described It has been linked with TSC, though occasionally, they can occur sporadically.[1] It most frequently occurs in the first decades of life Owing to its periventricluar location they frequently obstruct the ventricular pathway producing symptoms of raised pressure with other clinical manifestations being seizure, mental retardation, cognitive disability, and visual disturbances Computed tomography (CT) shows uniformly dense lesion with occasional peripheral calcifications These are commonly homogenous lesions with occasional cystic changes that appear isohypointese on T1‑weighted (T1W) and hyperintense on T2W images with marked contrast enhancement Histologically it is composed of three types of cells: Swollen gemistocytic cells, fibrillated spindle cells, and giant ganglion‑like cells.[1] There are large polygonal cells with abundant cytoplasm arranged in sheets, clusters, or pseudorosettes with different degrees of vascularization, angiocentric pattern, and calcifications Few cases may show anaplastic features like nuclear pleomorphism, mitosis, necrosis, microvascular proliferation, and increased Ki‑67 index; but traditionally these high‑grade features have been said not to impact the diagnosis or prognosis.[4] These high‑grade histologic features may easily lead to misdiagnosis of glioblastoma Absence of atypical small cells, low mitotic count, and Ki 67 index as compared to glioblastoma have been suggested to be the best discriminative features.[4] In spite of presence of necrosis and mitosis, the biological behavior of these atypical tumors is not aggressive and does not mandate radiotherapy and chemotherapy However, cases of atypical SEGA have been described in young children with a more rapid growth pattern due to malignant change and hemorrhage.[4,5] 547 [Downloaded free from http://www.neurologyindia.com on Thursday, November 13, 2014, IP: 202.177.173.189]  ||  Click here to download free Android application for journal Letters to Editor In our case the tumor recurred very rapidly and the clinical course was almost similar to malignant tumors In contrast to the traditional belief, our patient showed concordance between high‑grade histological features and the clinical outcome So it is difficult to prognosticate these atypical SEGAs and the clinical course may vary in different cases Utmost caution should be exercised in managing these patients Those with aggressive course should probably be treated as other malignant gliomas Devi Prasad Patra, Pravin Salunke, Debajyoti Chatterjee1, R K Vasishta1 Departments of Neurosurgery, and 1Histopathology, Post Graduate Institute of Medical Education and Research, Chandigarh, India E‑mail: drpravin_salunke@yahoo.co.uk References Ouyang T, Zhang N, Benjamin T, Wang L, Jiao J, Zhao Y, et al Subependymal giant cell astrocytoma: Current concepts, management, and future directions Childs Nerv Syst 2014;30:561‑70 Telfeian AE, Judkins A, Younkin D, Pollock AN, Crino P Subependymal giant cell astrocytoma with cranial and spinal metastases in a patient with tuberous sclerosis Case report J Neurosurg 2004;100 (5 Suppl Pediatrics):498‑500 Ogiwara H, Morota N Subependymal giant cell astrocytoma with intratumoral hemorrhage J Neurosurg Pediatr 2013;11:469‑72 Svajdler M Jr, Dếk L, Rychlý B, Talarčík P, Frưhlichová L Subependymal giant cell astrocytoma with atypical clinical and pathological features: A diagnostic pitfall Cesk Patol 2013;49:76‑9 Grajkowska W, Kotulska K, Jurkiewicz E, Roszkowski M, Daszkiewicz P, Jóźwiak S, et al Subependymal giant cell astrocytomas with atypical histological features mimicking malignant gliomas Folia Neuropathol 2011;49:39‑46 nerves Schwannomas arising from the oculomotor nerve are very rare, except with neurofibromatosis Approximately 40 cases of oculomotor nerve schwannomas have been described in the literature, of which 12 cases were large (≥2.5cm)[1,2] tumors This report presents a case of giant oculomotor nerve schwannoma A 24‑year‑old female complained of progressive diplopia, ptosis of left eye for 2 years These complaints were overlooked by family members For the last six months, she had developed gradual progressive visual loss of left eye followed by right eye She also used to have generalized headache, vomiting and features suggesting hypo‑function of pituitary gland On examination, her visual acuity was figure counting at meter distance in both the eyes with left oculomotor nerve palsy and bilateral optic atrophy Magnetic resonance imaging (MRI) of brain revealed a large, enhancing mass (6.1 × 3.6 × 6.2 cm) with central necrosis involving sellar and suprasellar regions, extending into left middle cranial fossa [Figures 1 and 2] Left pterional craniotomy and wide splitting of the Sylvian fissure for tumor access was carried out A large encapsulated, white, firm, moderately vascular, multilobulated tumor was found with a necrotic yellowish central zone Intratumoural decompression, followed by dissection of tumor in arachnoid plane carried out Though the tumor was abutting internal carotid artery Access this article online Quick Response Code: Website: www.neurologyindia.com PMID: *** DOI: 10.4103/0028-3886.144458 Received: 13-10-2014 Review completed: 14-10-2014 Accepted: 15-10-2014 Figure 1: An axial T1- and T2-weighted MRI scan showing (T1-hypointense and T2-hyperintense) sellar mass with left parasellar extension Giant oculomotor nerve schwannoma presenting as a sellar and suprasellar mass with parasellar extension Sir, Schwannomas account for 7% of all intracranial tumors and commonly arise from the vestibulocochlear and trigeminal 548 Figure 2: Coronal and sagittal gadolinium-enhanced contrast T1weighted MRI scan showing the said enhancing mass with central area of hypointensity The lesion was compressing the optic chiasma with ipsilateral carotid encasement Neurology India | Sep-Oct 2014 | Vol 62 | Issue Copyright of Neurology India is the property of Medknow Publications & Media Pvt Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission However, users may print, download, or email articles for individual use