glioblastoma multiforme ( gbm ) is the most common malignant primary brain tumor but considered as extremely rare in patients < 30 years old . the majority of the hemispheric tumors in children are gliomas , of which 6.5% of them constitute high - grade gliomas . we report a case of gbm in a teenage boy , where enlarged head size with sutural diastasis masquerading as hydrocephalus which delayed the primary diagnosis . after imaging , with provisional diagnosis of gbm intra - operatively , erosion of skull with sutural diastases is not reported in the pediatric primary gbm ; however , only reported in older ages in the form of isolated case reports . a 13-year - old boy resident of remote village presented with progressive headache and vomiting for last 6 months and left sided hemiparesis for 2 weeks . he first consulted local physician 4 months back , who observed large head size [ figure 1 ] , fundus examination revealed papilledema , and a presumed diagnosis of hydrocephalus was made , subsequently frusemide and phenytoin as antiepileptic medication was started although computed tomography ( ct ) scan was not done . on arrival in causality at current admission , he was intubated , examination on admission revealed head was enlarged with sutural diastases , glasgow coma scale ( gcs ) was e4 v2 m5 , fundi showed papilledema with left facial nerve upper motor neuron paresis with hypertonia in all limbs , left sided grade 2/5 hemiparesis with exaggerated deep tendon reflexes and bilateral plantar extensor response . hematological examination was within normal limits except hemoglobin which was 14 gm / dl , due to repeated vomiting . ct scan of brain showed a large heterogeneous mass lesion over right frontoparietal region causing significant mass effect with massive perilesional edema with midline shift of 1.2 cm toward left side with effacement of ipsilateral lateral ventricle and gross subfalcine herniation with transtentotrial herniation of medial temporal lobe [ figure 2a ] . magnetic resonance imaging brain t1-wighted image ( t1-wi ) , axial section showed a mass lesion measuring 10.8 cm  5.5 cm  6.9 cm , heterogeneous with iso and hyperintense areas with area of cystic degeneration [ figure 3a ] , which on t2-wi , showed heterogeneous mass with areas of hyperintensity like cerebrospinal fluid intensity with marked perilesional edema and subfalcine herniation and transtentorial herniation and gross midline shift [ figure 3b ] . a provisional diagnosis of malignant glioma was considered and planned for emergency craniotomy and resection . ( a ) noncontrast computed tomography head showing large heterogeneous lesion over right frontoparietal region causing significant mass effect with massive perilesional edema with midline shift of 1.2 cm toward left . ( b ) bone window computed tomography head view showing sutural diastases magnetic resonance imaging brain ( a ) t1-weighted image , axial section mass lesion of size measuring 10.8 cm  5.5 cm  6.9 cm , heterogeneous with iso to hyperintense with area of cystic degeneration . ( b ) t2-weighted image , showing heterogeneous mass with areas of hyperintensity such as cerebrospinal fluid intensity with marked perilesional edema . ( c ) contrast enhanced magnetic resonance imaging of the brain showing patchy mixed intensity contrast enhancing lesion he underwent large , right frontotemporoparietal craniotomy . after raising scalp flap , thinned out calvaria over the frontoparietal region , was observed with sutural diastasis . the bone flap showed areas of erosion over right parietal and frontal region [ figure 4a ] , and the dura was intact without evidence of deposit of tumor in the extradural space , [ figure 4b ] . however , dura remained tense even after mannitol infusion and starting total intravenous anesthesia , and stopping volatile and nitrous oxide anesthetic agent , after dural opening , brain bulge was observed , tumor was reaching up - to the surface with effaced sulci and discolored cortical surface . during decompression , tumor was highly vascular with heterogeneous consistency and presence of large thrombosed vessels . expansible towering , lax duraplasty carried out using pericranium . in the immediate postoperative period , he was kept on ventilatory support and extubated after 2 days , postoperative ct scan head showed radical excision of lesion with good operative cavity with complete subsidence of midline shift and mass effect [ figure 5 ] . he improved to gcs score e4 m6 v4 , tone reduced and hemiparesis improved to grade 4/5 . histopathology of specimen was who grade iv , gbm , on immunohistochemistry , it was glial fibrillary acidic protein positive , mib-1 index was about 20% , positive for p53 index . the patient received postoperative radiotherapy of 54 gy in 28 fractions and chemotherapy at the radiotherapy department . follow - up at 6 months following surgery , he was doing well and ambulatory and regularly attending school . intra - operative photograph : ( a ) bone flap showed areas of destruction over parietal and frontal region . ( b ) grossly intact dura without evidence of extradural deposit of tumor noncontrast computed tomography scan ( postoperative ) head showed radical excision of lesion with good operative cavity with complete subsidence of midline shift and mass effect gbm is most common glial tumor in adults , commonly associated with poor prognosis , with a median survival of about 12 months or less with surgery and adjuvant therapy . gbm is usually considered as rare neoplasm in patient < 30 years of age , and further pediatric gbm is quite rarer accounting for approximately 6.5% . however , tumors involving greater part of one hemispheric are usually gliomas , being common in both children as well as adults , and most of these are low - grade gliomas , and rarely a gbm . however , current case had symptoms for last 6 months presenting with enlargement of head , sutural diastasis , which closely mimicking hydrocephalus caused delay in diagnosis , as physician advised ct scan head ; however , patient could not afford imaging study especially in resource constraint country . low - grade gliomas can lead to remodeling of calvarium , due to chronic mass effect ; however , remodeling causing enlarged head size with gbm is not reported in literature in pediatric gbm . topographically gbm is predominantly located in supratentorial region , in order of decreasing frequency most often occurs in temporal lobe ( 32% ) , frontal ( 31% ) , frontoparietal ( 11% ) , and parietal ( 10% ) , respectively . the primary calvarial erosion and transdural spread occur spontaneously in the absence of any prior surgical intervention or irradiation and its incidence is quite rare , unlike the more common secondary type which occurs after previous insult or intervention including past craniotomy for tumor decompression , biopsy or repeated surgery for recurrent lesion or brachytherapy following surgical decompression . however , some intracranial tumors especially meningioma are known to penetrate dura and bone and infiltrating adjoining soft tissue . however , dural invasion and calvarial destruction by gbm leading to an outward growth are extremely rare . primary gbm does not involve normally surrounding dura and skull but reported in the form of isolated case report , which all occurred in adult or elderly population , none in the pediatric age group . kawano et al . postulated potential three routes for extradural spread of primary intracranial tumor first along the perivascular space along the vessel or dural sheaths , second along adjoining spinal or cranial nerves , and third by directly causing dural destruction overlying gbm . mechanism of secondary calvarial erosion and transdural spread : dural defect created during previous surgery can provide conduit for transdural migration and being further assisted by high intracranial tension secondary to recurrence of tumor , calvarial destruction and even infiltration of overlying scalp . reported supratentorial gbm causing skull erosions secondary to parietal gbm , reported to had calvarial involvement with associated scalp involvement in a 68-year - old male with transdural spread and microscopic invasion of dura . gbm can very rarely have distant spread as reported by kleinschmidt - demasters , who analyzed two cases adult cases , had craniotomy surgery for tumor decompression previously for gbm , and intra - operatively both cases had evidence of dural involvement . following surgery , both developed diffusely metastatic bone marrow involvement causing hemorrhagic diatheses from their diffuse bony disease . however , the current case is unique as presentation with enlarged head size , sutural separation , and primary calvarial erosion as a combination is rare occurrence .
authors report a rare case of supratentorial glioblastoma multiforme in a 13-year - old boy , who had headache , vomiting and left sided hemiparesis for last 6 months . on evaluation by primary physician 
 he was labeled as hydrocephalus in view of enlarged head with papilledema on fundoscopic evaluation and no imaging was carried out . on current admission , 
 magnetic resonance imaging brain revealed a large heterogeneous mass lesion involving right frontoparietal region associated with massive perilesional edema causing significant mass effect . 
 he underwent right fronto - temporal craniotomy and intraoperatively erosion of parietal bone was observed , unassociated with any extradural deposit of tumor . after surgery 
 , he noticed improvement in headache along with hemiparesis . 
 primary calvarial erosion in glioblastoma is extremely rare , and there is paucity of literature as evident from the few case reports reported previously and all occurred in elderly , so current case is the first pediatric case having primary calvarial erosion . 
 management of such case and pertinent literature is briefly discussed .