- Email: [email protected]
chiasmatic region
Case Reports / Journal of Clinical Neuroscience 33 (2016) 217–220
217
Spontaneous intratumoural and intraventricular haemorrhage associated with a pilomyxoid astrocytoma in the hypothalamic/ chiasmatic region Zhe Wang, Hong-Mei Yan ⇑, Xiu-Rong Zhou, Jin-Kai Liu, Jian-Yong Chang, Yu-Ting Wang Department of Neurosurgery, Wei Fang People’s Hospital, 151 Guangwen Street, Weifang 261041, China
a r t i c l e
i n f o
Article history: Received 4 December 2015 Accepted 14 March 2016
Keywords: Haemorrhage Hypothalamic/chiasmatic region Pilomyxoid astrocytoma Treatment
a b s t r a c t Pilomyxoid astrocytoma (PMA) is a rare, low-grade glioma that is recognised as a variant of pilocytic astrocytoma. There have been few reports on this pathologic entity presenting with spontaneous haemorrhage. In this study, we report a rare case of PMA in the hypothalamic/chiasmatic region presenting with intratumoural and intraventricular haemorrhage. An external ventricular drain was urgently inserted. A ventriculo-peritoneal shunt (VP) was undergone 4 weeks thereafter. The patient received fractionated Gamma Knife radiosurgery in another hospital 3 weeks after the VP shunt. Three months later, subtotal resection of the tumour was performed in our hospital via a pterional approach. The pathological diagnosis was PMA. Postoperatively, no adjuvant therapy was given, and the neurologic deficits were improved. However, the presentation of endocrine deficits remained. Notably, PMAs in the hypothalamic/chiasmatic region presenting with massive intratumoural and intraventricular haemorrhage may result in a severe condition and long-term impairment of endocrine function. Long-term follow-up is required to monitor the recurrence of the tumour and endocrinopathy. Ó 2016 Elsevier Ltd. All rights reserved.
1. Introduction Pilomyxoid astrocytoma (PMA) is a rare, low-grade glioma that is recognised as a variant of pilocytic astrocytoma (PA). Tihan et al. described a series of patients with PMA, which showed histologically and clinically different features from PA, and cited the difficulty of gross total resection because the tumours are commonly located in the hypothalamic/chiasmatic regions [1]. The number of reports on PMA has recently increased, but there have been few studies on this pathologic entity presenting with spontaneous haemorrhage [2–4]. We report a rare case of PMA in the hypothalamic/chiasmatic region presenting with massive intratumoural and intraventricular haemorrhage and discuss the clinical features and treatment of this tumour with regard to the literature. 2. Case report 2.1. History and examination A 13-year-old boy with sudden headache and vomiting presented to our hospital. He had severe visual impairment and became comatose immediately. Moreover, he presented with severe evidence of hypothalamic and pituitary dysfunction, including hypernatremia and diabetes insipidus. CT scan of the head showed massive intratumoural and intraventricular haemorrhage with marked hydrocephalus (Fig. 1A, B). MRI revealed a large lesion in the suprasellar region and enlarged ventricles with massive acute haemorrhage (Fig. 1C). An angiogram was obtained, which was negative for cerebrovascular abnormalities. 2.2. Treatment course An external ventricular drain was urgently inserted. After this procedure, the general condition of the patient improved. ⇑ Corresponding author. Tel.: +86 536 2603780. E-mail address: [email protected] (H.-M. Yan).
Ventriculo-peritoneal (VP) shunt was performed 4 weeks thereafter. The patient’s family refused the surgical resection of the lesion. The patient was transferred to another hospital, where he received fractionated gamma knife radiosurgery (GKRS) two sessions 3 weeks after the VP shunt; the marginal dose administered per session was 6 Gy. Therefore, the cumulative dose of 12 Gy was prescribed at the tumour margin. The prescription isodose was 45%. The patient’s neurologic status deteriorated 3 months after the fractionated GKRS. An MRI study of the neuraxis revealed growth of the tumour size (Fig. 2A). There was no evidence of leptomeningeal and spinal dissemination. The patient was transferred back to our hospital for further surgical debulking of the tumour. Craniotomy tumour removal was performed via a pterional approach. The tissue extended into the third ventricle and involved the hypothalamus. Subtotal resection was performed to avoid damage to the hypothalamus.
2.3. Pathologic findings A microscopic examination of the tissue showed a glial neoplasm composed of monomorphous, bipolar cells with a myxoid background. No Rosenthal fibres or eosinophilic granular bodies were detected. Immunocytochemistry showed an astroglial immunophenotype positive for glial fibrillary acidic protein (GFAP). The pathological diagnosis was PMA (Fig. 3A, B).
2.4. Postoperative course Some neurologic deficits were obviously improved postoperatively. However, the endocrinopathy with hypopituitarism and diabetes insipidus remained. The patient required pituitary hormone replacement and treatment for diabetes insipidus. Followup MRI studies of the neuraxis obtained at 3 and 10 months after the resection indicated no evidence of tumour recurrence (Fig. 2B, C). There was also no evidence of leptomeningeal and spinal dissemination. No adjuvant therapy was given after the sur-
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Case Reports / Journal of Clinical Neuroscience 33 (2016) 217–220
Fig. 1. CT scan of the head showing a mass lesion in the suprasellar region with (A) haemorrhage and (B) intraventricular haemorrhage with marked hydrocephalus. (C) Sagittal T1-weighted MRI revealing a lesion in the suprasellar region with haemorrhage and hydrocephalus.
gery. At the time of this writing, the neurologic evaluation of the patient showed stable results. 3. Discussion Patients with PMAs rarely present with spontaneous haemorrhage [5]. The mechanism that results in haemorrhages in this type of low-grade astrocytoma is not well understood [6,7]. Gottfried et al. reported the first case of a PMA of the temporal lobe presenting with intratumoural haemorrhage. They proposed the possibility of blood obscuring the histologic changes that contribute to the haemorrhage [6]. Hamada et al. described a patient with a PMA in the suprasellar region presenting with intratumoural haemorrhage; the occurrence of intratumoural and intraventricular haemorrhage during adjuvant chemotherapy 4 months after the operation was fatal. They presumed that the second haemorrhage was possibly associated with the neurotoxicities of the chemotherapeutic agents and the partial resection of the tumour [8]. In the present case, the patient initially presented with massive intratumoural and intraventricular haemorrhage. Such a case is very rarely described in the neurosurgical literature. The mechanisms underlying the haemorrhage associated with this type of tumour remain unclear. It was possible that intratumoural
bleeding broke into the third ventricle adjacent to the tumour and spread to the whole ventricular system. PMAs may occur anywhere along the neuraxis; however, they exhibit predilection for the hypothalamic/chiasmatic region and tend to affect very young children. The management of PMAs in the hypothalamic/chiasmatic region among children is challenging and remains controversial [9]. Any intervention should be carefully performed considering the potential risk of treatment-related morbidity. Goodden et al. suggest that surgical debulking has a clear role in diagnosis, tumour control and relief of mass effect. Partial resection can be primarily used as a safe and effective treatment for PMA [10]. However, Massimi et al. regard surgery not as the initial treatment but as an intervention of last resort with a potentially high risk [11]. Tsugu et al. point that chemotherapy should be used as the main treatment for PMA in the hypothalamic/chiasmatic region. The particular advantages of chemotherapy are that it can be given to younger children with relatively low rates of associated complications and low risks of long-term effects [12]. Radiotherapy is considered to be effective in controlling the growth of PMA; however, the late side effects of radiotherapy have led to its decreased use. Avoidance of radiotherapy is recommended for patients less than 5 years old [10,11,13]. Stereotactic radiosurgery (SRS) allows for the delivery of high-dose radiation
Case Reports / Journal of Clinical Neuroscience 33 (2016) 217–220
219
Fig. 2. (A) Sagittal Gd-DTPA–enhanced MRI obtained 3 months after fractionated Gamma Knife radiosurgery revealing a growth of the tumour size. (B) Sagittal Gd-DTPA– enhanced MRI obtained 3 months after the operation demonstrating no evidence of tumour recurrence. (C) Sagittal Gd-DTPA–enhanced MRI obtained 10 months after the operation showing no evidence of tumour recurrence.
Fig. 3. (A) Photomicrograph of tumour tissue showing monomorphic cells with a predominantly myxoid background. Haematoxylin and eosin, original magnification 400. (B) Positive immunoreaction to glial fibrillary acidic protein (GFAP). Original magnification 400.
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Case Reports / Journal of Clinical Neuroscience 33 (2016) 217–220
to tumours in critical locations while minimising the potential long-term toxicities of conventional radiotherapy [14]. Fractionated SRS can provide a compromise that offers the efficacy of SRS and safety of fractionated radiotherapy. Jee et al. suggest that fractionated GKRS should be considered as a safe tool for increasing the probability of tumour control and preserving visual function for perioptic tumour intervention. However, the optimal dose and fractions remain uncertain [15]. In the present patient, massive intratumoural and intraventricular haemorrhage resulted in a critical condition that made the treatment more complicated. The patient underwent urgent external ventricular drainage and then VP shunt for hydrocephalus. The subsequent fractionated GKRS was delivered in two sessions. According to the results of MRI follow-up, postoperative histological examination and clinical presentation, the treatment was ineffective, possibly due to the short-term follow-up and low dose prescribed at the tumour margin [16,17]. Subtotal resection was performed via a pterional approach to avoid damage to the hypothalamus/chiasmatic region. Gross total resection was not considered feasible because of the high risk of hypothalamic damage, endocrine deficits and blindness [10]. In general, patients with PMAs in the hypothalamic/chiasmatic region have a poor prognosis with a decreased rate of progressionfree survival, an increased rate of local recurrence of the tumour and more frequent dissemination in the leptomeninges and spinal cord [1–3]. In the patient under study, the neurologic deficits were improved postoperatively. However, the presentation of endocrine deficits remained. The endocrine function was clearly impaired, initially by the tumour itself and then further by the sudden massive intratumoural and intraventricular haemorrhage. Moreover, the intervention used to control the tumour, including GKRS and subtotal resection, could have deteriorated the patient’s condition. The patient required pituitary hormone replacement for hypopituitarism and treatment for diabetes insipidus. Close collaboration with an endocrinologist from the time of first presentation, and throughout the treatment period, is clearly important [10]. The patient should be continuously and closely monitored for potential recurrence of the tumour and endocrinopathy through imaging and clinical examinations over a long period. 4. Conclusion It is important to note that PMAs in the hypothalamic/ chiasmatic region presenting with massive intratumoural and intraventricular haemorrhage may result in a severe condition http://dx.doi.org/10.1016/j.jocn.2016.03.033
and long-term impairment of endocrine function. Long-term follow-up is required to monitor the recurrence of the tumour and endocrinopathy.
Conflicts of Interest/Disclosures The authors declare that they have no financial or other conflicts of interest in relation to this research and its publication. References [1] Tihan T, Fisher PG, Kepner JL, et al. Pediatric astrocytomas with monomorphous pilomyxoid features and a less favorable outcome. J Neuropathol Exp Neurol 1999;58:1061–8. [2] Darwish B, Koleda C, Lau H, et al. Juvenile pilocytic astrocytoma ‘pilomyxoid variant’ with spinal metastases. J Clin Neurosci 2004;11:640–2. [3] Forbes JA, Mobley BC, O’Lynnger TM, et al. Pediatric cerebellar pilomyxoidspectrum astrocytomas. J Neurosurg Pediatr 2011;8:90–6. [4] Pereira FO, Lombardi IA, Mello AY, et al. Pilomyxoid astrocytoma of the brainstem. Rare Tumors 2013;5:65–7. [5] Linscott LL, Osborn AG, Blaser S, et al. Pilomyxoid astrocytoma: expanding the imaging spectrum. AJNR Am J Neuroradiol 2008;29:1861–6. [6] Gottfried ON, Fults DW, Townsend JJ, et al. Spontaneous hemorrhage associated with a pilomyxoid astrocytoma. Case report. J Neurosurg 2003;99:416–20. [7] Lyons MK. Pilocytic astrocytoma with spontaneous intracranial hemorrhages in an elderly adult. Clin Neurol Neurosurg 2007;109:76–80. [8] Hamada H, Kurimoto M, Hayashi N, et al. Pilomyxoid astrocytoma in a patient presenting with fatal hemorrhage. Case report. J Neurosurg Pediatr 2008;1:244–6. [9] Komotar RJ, Mocco J, Carson BS, et al. Pilomyxoid astrocytoma: a review. MedGenMed 2004;6:42. [10] Goodden J, Pizer B, Pettorini B, et al. The role of surgery in optic pathway/ hypothalamic gliomas in children. J Neurosurg Pediatr 2014;13:1–12. [11] Massimi L, Tufo T, Di Rocco C. Management of optic-hypothalamic gliomas in children: still a challenging problem. Expert Rev Anticancer Ther 2007;7:1591–610. [12] Tsugu H, Oshiro S, Yanai F, et al. Management of pilomyxoid astrocytomas: our experience. Anticancer Res 2009;29:919–26. [13] Tjahjadi M, Arifin MZ, Sobana M, et al. Cystic pilomyxoid astrocytoma on suprasellar region in 7-year-old girl: treatment and strategy. Asian J Neurosurg 2015;10:154–7. [14] Kano H, Niranjan A, Kondziolka D, et al. Stereotactic radiosurgery for pilocytic astrocytomas part 2: outcomes in pediatric patients. J Neurooncol 2009;95:219–29. [15] Jee TK, Seol HJ, Im YS, et al. Fractionated gamma knife radiosurgery for benign perioptic tumors: outcomes of 38 patients in a single institute. Brain Tumor Res Treat 2014;2:56–61. [16] Kondziolka D, Shin SM, Brunswick A, et al. The biology of radiosurgery and its clinical applications for brain tumors. Neuro Oncol 2015;17:29–44. [17] Elias WJ, Khaled M, Hilliard JD, et al. A magnetic resonance imaging, histological, and dose modeling comparison of focused ultrasound, radiofrequency, and Gamma Knife radiosurgery lesions in swine thalamus. J Neurosurg 2013;119:307–17.
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Spontaneous intratumoural and intraventricular haemorrhage associated with a pilomyxoid astrocytoma in the hypothalamic/ chiasmatic region Zhe Wang, Hong-Mei Yan ⇑, Xiu-Rong Zhou, Jin-Kai Liu, Jian-Yong Chang, Yu-Ting Wang Department of Neurosurgery, Wei Fang People’s Hospital, 151 Guangwen Street, Weifang 261041, China
a r t i c l e
i n f o
Article history: Received 4 December 2015 Accepted 14 March 2016
Keywords: Haemorrhage Hypothalamic/chiasmatic region Pilomyxoid astrocytoma Treatment
a b s t r a c t Pilomyxoid astrocytoma (PMA) is a rare, low-grade glioma that is recognised as a variant of pilocytic astrocytoma. There have been few reports on this pathologic entity presenting with spontaneous haemorrhage. In this study, we report a rare case of PMA in the hypothalamic/chiasmatic region presenting with intratumoural and intraventricular haemorrhage. An external ventricular drain was urgently inserted. A ventriculo-peritoneal shunt (VP) was undergone 4 weeks thereafter. The patient received fractionated Gamma Knife radiosurgery in another hospital 3 weeks after the VP shunt. Three months later, subtotal resection of the tumour was performed in our hospital via a pterional approach. The pathological diagnosis was PMA. Postoperatively, no adjuvant therapy was given, and the neurologic deficits were improved. However, the presentation of endocrine deficits remained. Notably, PMAs in the hypothalamic/chiasmatic region presenting with massive intratumoural and intraventricular haemorrhage may result in a severe condition and long-term impairment of endocrine function. Long-term follow-up is required to monitor the recurrence of the tumour and endocrinopathy. Ó 2016 Elsevier Ltd. All rights reserved.
1. Introduction Pilomyxoid astrocytoma (PMA) is a rare, low-grade glioma that is recognised as a variant of pilocytic astrocytoma (PA). Tihan et al. described a series of patients with PMA, which showed histologically and clinically different features from PA, and cited the difficulty of gross total resection because the tumours are commonly located in the hypothalamic/chiasmatic regions [1]. The number of reports on PMA has recently increased, but there have been few studies on this pathologic entity presenting with spontaneous haemorrhage [2–4]. We report a rare case of PMA in the hypothalamic/chiasmatic region presenting with massive intratumoural and intraventricular haemorrhage and discuss the clinical features and treatment of this tumour with regard to the literature. 2. Case report 2.1. History and examination A 13-year-old boy with sudden headache and vomiting presented to our hospital. He had severe visual impairment and became comatose immediately. Moreover, he presented with severe evidence of hypothalamic and pituitary dysfunction, including hypernatremia and diabetes insipidus. CT scan of the head showed massive intratumoural and intraventricular haemorrhage with marked hydrocephalus (Fig. 1A, B). MRI revealed a large lesion in the suprasellar region and enlarged ventricles with massive acute haemorrhage (Fig. 1C). An angiogram was obtained, which was negative for cerebrovascular abnormalities. 2.2. Treatment course An external ventricular drain was urgently inserted. After this procedure, the general condition of the patient improved. ⇑ Corresponding author. Tel.: +86 536 2603780. E-mail address: [email protected] (H.-M. Yan).
Ventriculo-peritoneal (VP) shunt was performed 4 weeks thereafter. The patient’s family refused the surgical resection of the lesion. The patient was transferred to another hospital, where he received fractionated gamma knife radiosurgery (GKRS) two sessions 3 weeks after the VP shunt; the marginal dose administered per session was 6 Gy. Therefore, the cumulative dose of 12 Gy was prescribed at the tumour margin. The prescription isodose was 45%. The patient’s neurologic status deteriorated 3 months after the fractionated GKRS. An MRI study of the neuraxis revealed growth of the tumour size (Fig. 2A). There was no evidence of leptomeningeal and spinal dissemination. The patient was transferred back to our hospital for further surgical debulking of the tumour. Craniotomy tumour removal was performed via a pterional approach. The tissue extended into the third ventricle and involved the hypothalamus. Subtotal resection was performed to avoid damage to the hypothalamus.
2.3. Pathologic findings A microscopic examination of the tissue showed a glial neoplasm composed of monomorphous, bipolar cells with a myxoid background. No Rosenthal fibres or eosinophilic granular bodies were detected. Immunocytochemistry showed an astroglial immunophenotype positive for glial fibrillary acidic protein (GFAP). The pathological diagnosis was PMA (Fig. 3A, B).
2.4. Postoperative course Some neurologic deficits were obviously improved postoperatively. However, the endocrinopathy with hypopituitarism and diabetes insipidus remained. The patient required pituitary hormone replacement and treatment for diabetes insipidus. Followup MRI studies of the neuraxis obtained at 3 and 10 months after the resection indicated no evidence of tumour recurrence (Fig. 2B, C). There was also no evidence of leptomeningeal and spinal dissemination. No adjuvant therapy was given after the sur-
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Case Reports / Journal of Clinical Neuroscience 33 (2016) 217–220
Fig. 1. CT scan of the head showing a mass lesion in the suprasellar region with (A) haemorrhage and (B) intraventricular haemorrhage with marked hydrocephalus. (C) Sagittal T1-weighted MRI revealing a lesion in the suprasellar region with haemorrhage and hydrocephalus.
gery. At the time of this writing, the neurologic evaluation of the patient showed stable results. 3. Discussion Patients with PMAs rarely present with spontaneous haemorrhage [5]. The mechanism that results in haemorrhages in this type of low-grade astrocytoma is not well understood [6,7]. Gottfried et al. reported the first case of a PMA of the temporal lobe presenting with intratumoural haemorrhage. They proposed the possibility of blood obscuring the histologic changes that contribute to the haemorrhage [6]. Hamada et al. described a patient with a PMA in the suprasellar region presenting with intratumoural haemorrhage; the occurrence of intratumoural and intraventricular haemorrhage during adjuvant chemotherapy 4 months after the operation was fatal. They presumed that the second haemorrhage was possibly associated with the neurotoxicities of the chemotherapeutic agents and the partial resection of the tumour [8]. In the present case, the patient initially presented with massive intratumoural and intraventricular haemorrhage. Such a case is very rarely described in the neurosurgical literature. The mechanisms underlying the haemorrhage associated with this type of tumour remain unclear. It was possible that intratumoural
bleeding broke into the third ventricle adjacent to the tumour and spread to the whole ventricular system. PMAs may occur anywhere along the neuraxis; however, they exhibit predilection for the hypothalamic/chiasmatic region and tend to affect very young children. The management of PMAs in the hypothalamic/chiasmatic region among children is challenging and remains controversial [9]. Any intervention should be carefully performed considering the potential risk of treatment-related morbidity. Goodden et al. suggest that surgical debulking has a clear role in diagnosis, tumour control and relief of mass effect. Partial resection can be primarily used as a safe and effective treatment for PMA [10]. However, Massimi et al. regard surgery not as the initial treatment but as an intervention of last resort with a potentially high risk [11]. Tsugu et al. point that chemotherapy should be used as the main treatment for PMA in the hypothalamic/chiasmatic region. The particular advantages of chemotherapy are that it can be given to younger children with relatively low rates of associated complications and low risks of long-term effects [12]. Radiotherapy is considered to be effective in controlling the growth of PMA; however, the late side effects of radiotherapy have led to its decreased use. Avoidance of radiotherapy is recommended for patients less than 5 years old [10,11,13]. Stereotactic radiosurgery (SRS) allows for the delivery of high-dose radiation
Case Reports / Journal of Clinical Neuroscience 33 (2016) 217–220
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Fig. 2. (A) Sagittal Gd-DTPA–enhanced MRI obtained 3 months after fractionated Gamma Knife radiosurgery revealing a growth of the tumour size. (B) Sagittal Gd-DTPA– enhanced MRI obtained 3 months after the operation demonstrating no evidence of tumour recurrence. (C) Sagittal Gd-DTPA–enhanced MRI obtained 10 months after the operation showing no evidence of tumour recurrence.
Fig. 3. (A) Photomicrograph of tumour tissue showing monomorphic cells with a predominantly myxoid background. Haematoxylin and eosin, original magnification 400. (B) Positive immunoreaction to glial fibrillary acidic protein (GFAP). Original magnification 400.
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Case Reports / Journal of Clinical Neuroscience 33 (2016) 217–220
to tumours in critical locations while minimising the potential long-term toxicities of conventional radiotherapy [14]. Fractionated SRS can provide a compromise that offers the efficacy of SRS and safety of fractionated radiotherapy. Jee et al. suggest that fractionated GKRS should be considered as a safe tool for increasing the probability of tumour control and preserving visual function for perioptic tumour intervention. However, the optimal dose and fractions remain uncertain [15]. In the present patient, massive intratumoural and intraventricular haemorrhage resulted in a critical condition that made the treatment more complicated. The patient underwent urgent external ventricular drainage and then VP shunt for hydrocephalus. The subsequent fractionated GKRS was delivered in two sessions. According to the results of MRI follow-up, postoperative histological examination and clinical presentation, the treatment was ineffective, possibly due to the short-term follow-up and low dose prescribed at the tumour margin [16,17]. Subtotal resection was performed via a pterional approach to avoid damage to the hypothalamus/chiasmatic region. Gross total resection was not considered feasible because of the high risk of hypothalamic damage, endocrine deficits and blindness [10]. In general, patients with PMAs in the hypothalamic/chiasmatic region have a poor prognosis with a decreased rate of progressionfree survival, an increased rate of local recurrence of the tumour and more frequent dissemination in the leptomeninges and spinal cord [1–3]. In the patient under study, the neurologic deficits were improved postoperatively. However, the presentation of endocrine deficits remained. The endocrine function was clearly impaired, initially by the tumour itself and then further by the sudden massive intratumoural and intraventricular haemorrhage. Moreover, the intervention used to control the tumour, including GKRS and subtotal resection, could have deteriorated the patient’s condition. The patient required pituitary hormone replacement for hypopituitarism and treatment for diabetes insipidus. Close collaboration with an endocrinologist from the time of first presentation, and throughout the treatment period, is clearly important [10]. The patient should be continuously and closely monitored for potential recurrence of the tumour and endocrinopathy through imaging and clinical examinations over a long period. 4. Conclusion It is important to note that PMAs in the hypothalamic/ chiasmatic region presenting with massive intratumoural and intraventricular haemorrhage may result in a severe condition http://dx.doi.org/10.1016/j.jocn.2016.03.033
and long-term impairment of endocrine function. Long-term follow-up is required to monitor the recurrence of the tumour and endocrinopathy.
Conflicts of Interest/Disclosures The authors declare that they have no financial or other conflicts of interest in relation to this research and its publication. References [1] Tihan T, Fisher PG, Kepner JL, et al. Pediatric astrocytomas with monomorphous pilomyxoid features and a less favorable outcome. J Neuropathol Exp Neurol 1999;58:1061–8. [2] Darwish B, Koleda C, Lau H, et al. Juvenile pilocytic astrocytoma ‘pilomyxoid variant’ with spinal metastases. J Clin Neurosci 2004;11:640–2. [3] Forbes JA, Mobley BC, O’Lynnger TM, et al. Pediatric cerebellar pilomyxoidspectrum astrocytomas. J Neurosurg Pediatr 2011;8:90–6. [4] Pereira FO, Lombardi IA, Mello AY, et al. Pilomyxoid astrocytoma of the brainstem. Rare Tumors 2013;5:65–7. [5] Linscott LL, Osborn AG, Blaser S, et al. Pilomyxoid astrocytoma: expanding the imaging spectrum. AJNR Am J Neuroradiol 2008;29:1861–6. [6] Gottfried ON, Fults DW, Townsend JJ, et al. Spontaneous hemorrhage associated with a pilomyxoid astrocytoma. Case report. J Neurosurg 2003;99:416–20. [7] Lyons MK. Pilocytic astrocytoma with spontaneous intracranial hemorrhages in an elderly adult. Clin Neurol Neurosurg 2007;109:76–80. [8] Hamada H, Kurimoto M, Hayashi N, et al. Pilomyxoid astrocytoma in a patient presenting with fatal hemorrhage. Case report. J Neurosurg Pediatr 2008;1:244–6. [9] Komotar RJ, Mocco J, Carson BS, et al. Pilomyxoid astrocytoma: a review. MedGenMed 2004;6:42. [10] Goodden J, Pizer B, Pettorini B, et al. The role of surgery in optic pathway/ hypothalamic gliomas in children. J Neurosurg Pediatr 2014;13:1–12. [11] Massimi L, Tufo T, Di Rocco C. Management of optic-hypothalamic gliomas in children: still a challenging problem. Expert Rev Anticancer Ther 2007;7:1591–610. [12] Tsugu H, Oshiro S, Yanai F, et al. Management of pilomyxoid astrocytomas: our experience. Anticancer Res 2009;29:919–26. [13] Tjahjadi M, Arifin MZ, Sobana M, et al. Cystic pilomyxoid astrocytoma on suprasellar region in 7-year-old girl: treatment and strategy. Asian J Neurosurg 2015;10:154–7. [14] Kano H, Niranjan A, Kondziolka D, et al. Stereotactic radiosurgery for pilocytic astrocytomas part 2: outcomes in pediatric patients. J Neurooncol 2009;95:219–29. [15] Jee TK, Seol HJ, Im YS, et al. Fractionated gamma knife radiosurgery for benign perioptic tumors: outcomes of 38 patients in a single institute. Brain Tumor Res Treat 2014;2:56–61. [16] Kondziolka D, Shin SM, Brunswick A, et al. The biology of radiosurgery and its clinical applications for brain tumors. Neuro Oncol 2015;17:29–44. [17] Elias WJ, Khaled M, Hilliard JD, et al. A magnetic resonance imaging, histological, and dose modeling comparison of focused ultrasound, radiofrequency, and Gamma Knife radiosurgery lesions in swine thalamus. J Neurosurg 2013;119:307–17.