the clinical presentation of these patients is varied , ranging from headache and focal neurological deficits to personality changes and/or mental deterioration , including memory loss , inattention , confusion , hallucination , and hyperphagia . as a result , these patients are often confused with encephalitis and its sequel , as happened in our patient .
the role of surgery is limited , owing to the architectural complexity and depth of location of the lesion .
an 8-year - old patient was referred to the pediatric emergency services with complaints of moderate- to high - grade fever for 10 days , 2 months back . on 5 day of fever ,
the patient developed choreoathetoid movements on right side of the body , which was more severe in the upper limb .
few days later , he developed progressive loss of ambulation , cognition , and speech . on examination , he was in a state of altered consciousness ( e2v2m5 ) . however , his vitals were stable .
the neurological assessment revealed , increased tone in all four limbs , with exaggerated deep tendon reflexes and bilateral extensor plantar reflex .
fundoscopy revealed mild papilledema , pupils were of normal size and reacting to light . his complete hematological profile and serum chemistries were unremarkable .
noncontrast computed tomography ( ct ) of the head revealed a bilateral thalamic iso- to hyperdense lesion with moderate hydrocephalus [ figure 1 ] .
the mr examination of the brain showed significant swelling of thalamus with diffuse hypointense signal on t1-weighted ( t1w ) imaging and hyperintense signal on t2 and fluid - attenuated inversion recovery ( flair ) sequences [ figure 2 ] .
hypointense signals on t1 and hyperintense signal changes on t2w and flair were also present in the basal ganglia , head of the caudate nuclei , and upper brainstem .
findings were considered nonspecific and diagnosis of encephalitis was considered , however , bilateral thalamic glioma was the second possibility .
noncontrast computed tomography of head reveals bilateral iso- to hyperdense thalamic masses with hydrocephalus and periventricular ooze t2-weighted magnetic resonance imaging reveals bilateral hyperintense thalamic masses with focal hypointensities t1-weighted axial post - contrast image reveals mild peripheral enhancement patient was managed on the lines of encephalitis and its sequelae .
he was started on antiepileptic drugs and decongestants to decrease raised intracranial pressure and a low pressure ventricular shunt was inserted .
histopathological examination of the biopsy specimen revealed a highly cellular tumor with foci of palisading necrosis [ figure 4a ] and microvascular proliferation [ figure 4b ] .
the tumor cells showed marked nuclear pleomorphism and frequent mitotic figures [ figure 4b ] , including atypical forms .
on immunohistochemistry , the tumor cells were immunopositive for p53 [ figure 4c ] and were negative for epidermal growth factor receptor ( egfr ) .
mib - i labeling index was approximately 60% in the highest proliferating areas [ figure 4d ] .
based on these features , a diagnosis of glioblastoma multiforme , world health organization ( who ) grade iv , was arrived at .
photomicrographs showing ( a ) a highly cellular tumor with foci of palisading necrosis ( hematoxylin and eosin ( h and e ) , original magnification 400 ) and ( b ) microvascular proliferation ( h and e , original magnification 400 ) .
( b ) the tumor cells display marked nuclear pleomorphism and frequent mitotic figures ( h and e , original magnification 400 ) .
( c ) immunohistochemistry for p53 showed nuclear positivity ( immunohistochemistry ( ihc ) , original magnification 400 ) .
( d ) mib - i labeling index is 60% ( ihc , original magnification 400 ) tracheostomy was done in view of poor glasgow coma scale ( gcs ) considering the need of prolonged ventilatory support .
although thalamic tumors constitute between 2 and 5% of all the pediatric intracranial tumors , it is only 1% in adult series .
bilateral pediatric thalamic glioblastomas are extremely rare and only five cases are published in the english literature . the largest series on pure thalamic tumors to date is from the necker enfants malades hospital , paris , which reported 69 children treated over a 14-year period .
lesions in the ventrolateral thalamus typically manifest with motor deficits , given their close proximity to the internal capsule .
the visual signs and symptoms are present in as many as 50% of these patients and are due to involvement of the optic tracts and the lateral geniculate body .
the oculomotor deficits are due to involvement of the retrolenticular segment of the internal capsule or the midbrain tegmentum .
involvement of the mammillothalamic tracts or the fornices can lead to cognitive dysfunction and memory problems .
bilateral thalamic lesions are associated with changes in personality , memory deficits , confusion , hallucinations , hyperphagia , and bradyphrenia .
diffuse and bilateral involvement of thalamic nuclei by these tumors makes the surgical therapy very difficult .
the role of surgery , hence , is limited and is performed for histological diagnosis as was done in our patient .
the role of chemotherapy and radiotherapy is of questionable significance and are utilized as adjuvant therapies .
bilateral thalamic tumors are typically treated with radiation therapy , regardless of whether they are histologically malignant . for bilateral thalamic tumors ,
the prognosis remains relatively poor regardless of tumor histology and treatment . in our patient , left thalamic tumor was biopsied under magnetic resonance imaging ( mri ) guidance .
, documented p53 protein accumulation in 75% of high - grade childhood gliomas , and p53 mutation in 38% .
pollack et al . , documented increased expression of p53 in about 35% of high - grade gliomas in children , which increased to 58% when only glioblastomas were considered .
the authors determined that this feature was an adverse prognostic factor in a cohort of children who were treated uniformly with surgery , radiotherapy , and chemotherapy . on the other hand ,
egfr amplification is much less common in pediatric glioblastomas compared to adult primary glioblastomas and the reports on egfr protein expression have been quite varied .
, who found only very small foci of tumor cells showing egfr immunopositivity in four of 13 glioblastomas .
thalamic lesions continue to be a challenging entity to the neurosurgeons , particularly owing to their deep location and complex circuitry .
unilateral tumors are increasingly being tackled by the neurosurgeons with an improved patient outcome . however ,
bilateral thalamic glioblastomas have a very poor prognosis , irrespective of the modality of treatment .
 bilateral thalamic tumors are rare . pediatric bilateral thalamic glioblastomas are even rarer , only five cases reported in the english literature till date 
 . the clinical presentation , natural history , and prognosis of pediatric thalamic tumors are still relatively obscure . in this article 
 , we report an 8-year - old patient with large bilateral thalamic glioblastomas and briefly discuss its clinical presentation , possible modalities of management , and prognosis , in the light of available literature . 
Introduction
Case Report
Discussion
Conclusion